Can it burn?
Incredibly dry, and powdered so that it mixes readily with air.
Under those conditions, even aluminum ignites with the heat of a simple match. Combustion, however, is the rapid oxidation of combustible matter... I suspect that silt is already mostly made of oxides and, hence, not really combustible. If you heat it enough, you probably would only melt it.
Any chemists on the boards?
What would you think of a spell that sets fire to silt? You pick a center and the fire radius spreads in a burst, but slowly, 10-60 feet per round, so you have a spreading ring of fire, extending to a max of --- I don't know how many feet.
In a case like that I'd say go ahead, just write up a spell, balance it and hand it in for DM approval. When dealing with magic I'd be find with a spell that sets water on fire like it's gasoline if you balanced it right.
As to it not filling in like water, my limited knowledge of Dark Sun and silt gave me the impression that silt is fully capable of flowing more freely than even water, thus wave action on the silt sea.
Where is that described? In still photos it looks like that, but so does a desert. More like dunes that waves.
In a case like that I'd say go ahead, just write up a spell, balance it and hand it in for DM approval. When dealing with magic I'd be find with a spell that sets water on fire like it's gasoline if you balanced it right.
Indeed. No need to keep things scientifically accurate, if we are dealing with magic.
It's not so much a balance question as an imagination question -- does this work artistically?
I believe so, yes. I find the image of a burning hole on the surface of the Sea of Silt to be appealing; smoke and the cloud of silt lifted by the fires add to the fog of war and to the visual impact of a combat scene. Also, the area could become littered with glass shards created by the melting of silt.
Silt Waves?
Where is that described? In still photos it looks like that, but so does a desert. More like dunes that waves.
Agreed. Silt must behave more like sand than like water. But it should become highly mobile if there is a storm going on...
However, when you heat the silt, I think you can melt it to some obsidian-like substance.
Dust ... part mineral, part vegetable matter, traces of animal matter. Incredibly dry, and powdered so that it mixes readily with air.
Can it burn?
Negative Brax, I tried in Kirkuk, Iraq. plenty of silt laden dried out riverbeds. was doing experiments with mud (added water to make bricks) made a fire pit and threw some in. NADA
So yea...silt pretty much can't burn, because if it could Dark Sun wouldn't be a very viable game world.
This post has been brought to you by the National Society For Safe Grain Storage Practices and the letter X.
I know it has been discussed before, and recently, but no search function, so no thread pointers
Oh. I must have missed it. Haven't been able to read through all the posts as I used to, lately.
but silt "flows" like water
Are you sure about this, greyorm? Given the tiny size of its particles, silt’s probably a whole lot more mobile than sand, but it shouldn’t behave like true fluids. Quicksand is highly fluidic because it is, really, water with silt or sand immersed in it.
Granted, even regular earth can slide back to the hole, if you aren’t careful when shoveling it. Digging through silt must be that much harder.
Any first hand experiences you can share with us, Galek?
Athas would have suffered from the equivalent of a giant "grain silo explosion" long ago.
I had heard about grain explosion. Same thing happens to chocolate dust. Without proper care, factories get their ceiling blown almost to orbit! 
If silt can catch fire, the whole Sea of Silt would have been burned away centuries ago
This makes sense; should have thought of it before. Then again, a whole sea made of silt is fairly surreal, so who knows?
Are you sure about this, greyorm? Given the tiny size of its particles, silt’s probably a whole lot more mobile than sand, but it shouldn’t behave like true fluids. Quicksand is highly fluidic because it is, really, water with silt or sand immersed in it.
True, and I may be mistaken/overstating the argument that was made, but I know we discussed giants wading, being immersed in silt, the effects of water on silt, and so forth, and the conclusion -- based on a number of sources describing the sea -- was that you could not dig in silt because it just filled right back in too quickly.
It would be like digging in uncompressed, very fine sand, and if you've ever tried to shovel very fine sand, you know it just fills itself right back in. My grandparents had a sand pit they sold sand out of, so I've actually done this and watched it happen...we also had a cement plant in our town complete with giant piles of fine sand we tried walking in as kids, sinking up to our knees or worse depending on how fresh the stuff was. Given how much lighter and smaller-grained the silt is, it would be even worse. And there's all the sand-dust and crap you stir up when you're digging, too. Again, it's gotta be that much worse with silt.
Sand is fluidic on a small scale. But pull out 1000 feet radius of sand, and you'll see it forming a downward cone. It slides in, but not to the same extent as water.
A silt skimmer, for example. will probably leave a trail in the silt. Not a trench, but a definite trail, unless the wind picks up.
-brax
Please check your pm, Raven. I think you have my domain blocked.
Actually, I've gotten the e-mail -- rather, I've gotten one of them -- but I haven't been at home long enough to sit down and respond to it (anything I've written to the boards or anywhere else this past week has been during my free-time during work).
Now, I don't know why I've only recieved one out of four, but as soon as I have the time to check into it, I will do so. Gah.
mud at the bottom of most larger/deeper areas of the silt sea
silt horrors :88E:
sand
very fine sand
ash and other dust particles
A lot of dwarf hair(I couldn't resist it had to go somewhere!)
The composition of silt is: [from bottom to top]
mud at the bottom of most larger/deeper areas of the silt sea
silt horrors :88E:
sand
very fine sand
ash and other dust particles
A lot of dwarf hair(I couldn't resist it had to go somewhere!)
Heh, seriously tho...
If we take real-world silt and apply it here, I think there would be a number of problems. Honestly, I think that Athasian Silt isn't quite so "pure" as real-world Silt. I'd say that there's a mix of what we know as silt, combined with dried dead oraganic particles (dust), and defiler's ash. It is extraordinarily fine particles, which does not take much of a breeze at all to quickly blow into the air. It also sits rather loosly upon itself in the once water-filled basins.
Once there, the sheer weight of so much silt packed on top of itself will eventually force the lower elements of it to pack down and become much firmer -- Giants walking around probably helps that considerably. Plus, if there is any water left at all in those basins, they'd be at the deepest points, making for some rather compact and hard mud, being trapped under the silt.
Digging through the silt, as raven noted, would be impossible, as it has many aspects similar to a fluid. However the increased surface area available for a chemical reaction would result in the Silt being probably quite flammable -- until the fire gets smothered, that is. Unless the Silt is composed of some noble or highly-chemical-bond resistant materials, I would rule that yes, it could catch fire. However the fire would need air & oxygen to really be able to continue and spread.
So, if a fire was to start out on the Sea of Silt, I'd think that the smoke combined with the already high levels of dust in the air would begin to choke off the fire, preventing it from spreading too far. It would burn down, rather than out, resulting in a localized depression within the area of the fire, and then the surrounding Silt would quickly fill in and smother out the rest of the fire. Sure, it could burn... but you'd need a hell of a lot of fire in order to have any kind of impact or effect on any great scale. A fireball might burn the surrounding area for a few turns before it gets smothered by the sheer volume of Silt in the surrounding areas. Even gasoline can be used to put out a fire, given enough gasoline.
Do note that "flammable" does not necessarily mean "combustable". You'd need a miracle set of conditions in place in order to get the right air/silt/temperature/pressure mixture in order to make it explode. The dust all across the silt basin would prevent the necessary sunlight needed for the temperature, plus the pressure would really be wrong. The silt in the air would choke off the needed oxygen, so the results would be something that could burn for a little bit (and then run out of oxygen to continue), but without the necessary pressure to cause an explosion.
In order for there to be a silt sea, let alone *anything* in that area, silt can't be combustable: If it was Athas would have suffered from the equivalent of a giant "grain silo explosion" long ago. In a nutshell, given a small enough particle, in a large enough quantity, at a specific density in relation to the air/oxygen around it, and at a certain pressure (or higher), you can get anything flammable to explode - even aluminum dust has been known to explode in factories where a lot of it was concentrated in one location. Although that's a pretty large set of variables we're dealing with, odds are that there'd be certain conditions within the silt sea that could cause this, and it's possible that it'd be a constant possibility - I imagine that out in the deep silt there's a certain "layer" of silt, at X number of feet above or below the "surface" of the sea, where you'd have just the right amount of silt, oxygen and pressure (caused by the silt around it) to cause an explosion. And if that were the case, even static electricity could cause enough of a spark to cause a small explosion, which increases the pressure of the silt around it and thus makes that silt explode, on and on until the entire sea erupts.
So yea...silt pretty much can't burn, because if it could Dark Sun wouldn't be a very viable game world.
This post has been brought to you by the National Society For Safe Grain Storage Practices and the letter X.
OK. What I see here is
1. Scientifically, a large body of silt like this should catch fire.
2. It MUSt not be flammable, otherwise the whole thing would have gone up a long time ago.
The most logical explanation of this is that it *did* catch fire, many king's ages ago, or parts of it caught fire during its initial formation, before it was one coherent mass, towards the end of the Cleansing Wars & the beginning of the time of the SKs. What remains now is already burnt out, oxidized.
Yes I know that we don't have to explain everything by science. But if science explains the status quo, I'm not sure why we'd need to avoid it.
With something of this magnitude I don't think even a scientist who specializes in "dust explosion calculation and prevention" could tell us exactly what would happen, at least not without having all the applicable data (which we don't have), but otherwise I think that the "burning out" idea would only work on silt that was sitting on the surface and with a regular fire; should an explosion occur at a deeper level, either due to natural or unnatural causes, and the silt was in fact combustable, then you'd have a chain reaction on your hands. True, the silt sea isn't contained within a silo, but it *is* large enough that the surrounding silt, to an extent, serves as its own silo of sorts; for instance, if you have ring of silt that has been compacted down (say because it's a giant trade-route, which has been described in various DS books as occuring at around 10' below the surface), and a large dust storm were to kick up that top layer of silt (which is not only possible but happens, as there are references to silt-covered ruins being exposed by silt storms...and if a previously-hidden building is uncovered, that means a good 10' of silt must have been blown out of the area as even a small building would likely stand 10' tall), then the "loose" silt contained within this ring of densely packed silt is, to an extend, equivalent to the contents of a grain silo. If this same storm were to start swirling air currents downward, you could end up with an "atmospheric roof" of air that'd increase the pressure in this "silt silo," and for all intents and purposes you've now got a self-contained system similar to a grain silo that has, theoretically, the same ability to explode...and in a system that is fueled by pressure, which is increased dramatically in the presence of an explosion, that sounds to me like it'd perpetuate itself.
I'll give that this is an extremely unlikely event...but at the same time, we are talking 2 millenia and many, many square miles of silt.
On the subject of sunlight/temperature/pressure, I think you're probably arguing against what would would really happen: the sunlight would heat the silt and air in the upper layers of the silt, which (through conduction...or is that convection?) would transfer down to the air and silt below it...and as temperature and pressure are directly proportional, this will increase the pressure of the lower levels of silt. Again, this is along the same lines as that of a grain silo, so I don't see why the introduction of a catalyst (flame or static electricity) wouldn't, theoretically, have a "happy zone" within this silt-medium where it could cause an explosion. After all, with a grain silo it's not the size of the initial pop that matters, its the fact that as long as there's enough oxygen available for that first little burst of energy then the entire system will be disturbed in such a way that the initially-miniscule explosion can turn into something immense.
Brax/Xlorep - The idea of "already burned" is probably the best bet here, if you want to get rid of the idea that the silt is completely non-combustable based on composition. The only problem with that is, why isn't it black? We'd have to come up with some other non-flammable substance (other than carbon), something "silt colored" (light grayish-tan, if I recall correctly; nearly white) that could be left over from many fires; for all we know the deepest layers of silt could be pitch black, containing the thicker "clumps" of carbon from previously-flammable materials that have settled down over the years. But at the surface level, and for probably 20'-30' down (at the absolute minimum, I think) there's got to be something else.
Xlorep - from the (albeit minimal) science I've read regarding "grain explosions," the biggest factor seemed to be attaining the correct pressure; it's the reason why blowing dust doesn't explode (normal atmospheric pressure) while dust kept in a silo can/does (high concentration in an enclosed area = higher pressure). As I mentioned earlier (and Brax just quoted), given the sheer size of the Silt Sea, all the atmospheric (both local and global) variables that affect it, and the two-thousand or so years that it's been there, you've got a lot of time for a relatively low chance for an explosion happening...but once it does the shockwave would displace nearby silt, very likely resulting in at least one new "pocket" of silt/oxygen that meets the requirements of heightened pressure plus "burnability" to explode itself, adding to the first explosion's force, and continuing on down the line in a chain reaction. And that scenario can occur without there even being any fire source applied to it (simple friction or static electricity could cause it).
With something of this magnitude I don't think even a scientist who specializes in "dust explosion calculation and prevention" could tell us exactly what would happen, at least not without having all the applicable data (which we don't have), but otherwise I think that the "burning out" idea would only work on silt that was sitting on the surface and with a regular fire; should an explosion occur at a deeper level, either due to natural or unnatural causes, and the silt was in fact combustable, then you'd have a chain reaction on your hands. True, the silt sea isn't contained within a silo, but it *is* large enough that the surrounding silt, to an extent, serves as its own silo of sorts; for instance, if you have ring of silt that has been compacted down (say because it's a giant trade-route, which has been described in various DS books as occuring at around 10' below the surface), and a large dust storm were to kick up that top layer of silt (which is not only possible but happens, as there are references to silt-covered ruins being exposed by silt storms...and if a previously-hidden building is uncovered, that means a good 10' of silt must have been blown out of the area as even a small building would likely stand 10' tall), then the "loose" silt contained within this ring of densely packed silt is, to an extend, equivalent to the contents of a grain silo. If this same storm were to start swirling air currents downward, you could end up with an "atmospheric roof" of air that'd increase the pressure in this "silt silo," and for all intents and purposes you've now got a self-contained system similar to a grain silo that has, theoretically, the same ability to explode...and in a system that is fueled by pressure, which is increased dramatically in the presence of an explosion, that sounds to me like it'd perpetuate itself.
I'll give that this is an extremely unlikely event...but at the same time, we are talking 2 millenia and many, many square miles of silt.
I don't understand, are you disagreeing with me or not? Because your argument does not conflict with my statements one bit. As I said, flammable does not mean conbustable. Wax is flammable, but I don't hear much about exploding wax candles. Linen is flammable, but I don't hear much about linen explosions either. Just because something can burn (is physically able to burn) that does not mean that it explodes. For an explosion to happen, you must have a proper mix of accelerant and fuel as well as pressure. Silo explosions happen when those conditions are met. Heat is important towards increasing the pressure in most chemical reactions, as well as promoting the reaction to actually happen. Silt, as I said, could be flammable -- as in, it is capable of being burned. However, it could need some extreme balance of Silt, oxygen, pressure, and I would bet temperature together in order to explode.
Deep in the silt, you'd most likely be lacking the oxygen necessary for the explosion. Or if you have the oxygen, the temperature to initiate the combustion probably isn't there. On the surface, you are completely lacking the pressure necessary for an explosion, however the mix of Silt and oxygen could possibly be enough to sustain a fire for a limited amount of time (until the fuel in the local area is used up enough to snuff it out)
On the subject of sunlight/temperature/pressure, I think you're probably arguing against what would would really happen: the sunlight would heat the silt and air in the upper layers of the silt, which (through conduction...or is that convection?) would transfer down to the air and silt below it...and as temperature and pressure are directly proportional, this will increase the pressure of the lower levels of silt. Again, this is along the same lines as that of a grain silo, so I don't see why the introduction of a catalyst (flame or static electricity) wouldn't, theoretically, have a "happy zone" within this silt-medium where it could cause an explosion. After all, with a grain silo it's not the size of the initial pop that matters, its the fact that as long as there's enough oxygen available for that first little burst of energy then the entire system will be disturbed in such a way that the initially-miniscule explosion can turn into something immense.
Your problem with the conduction sending the temperature down is that hot air expands, and thus rises. As the hot air rises, it lowers the temperature below, and tends to keep what is at a lower altitude at a cooler temperature. The sunlight would need incredible amounts of heat to affect it, which would make the air pressure actually decrease at lower altitudes, resulting int he Silt actually settling more, and the chances for explosion decreasing. Grain silos are enclosed systems with a lot of grain in a limited area, temperatures increase, but the heat escapes much more slowly, setting up a far more combustion-prone situation all around.
Brax/Xlorep - The idea of "already burned" is probably the best bet here, if you want to get rid of the idea that the silt is completely non-combustable based on composition. The only problem with that is, why isn't it black? We'd have to come up with some other non-flammable substance (other than carbon), something "silt colored" (light grayish-tan, if I recall correctly; nearly white) that could be left over from many fires; for all we know the deepest layers of silt could be pitch black, containing the thicker "clumps" of carbon from previously-flammable materials that have settled down over the years. But at the surface level, and for probably 20'-30' down (at the absolute minimum, I think) there's got to be something else.
I'm not a fan of the "already burned" idea -- I think that while it can burn, it is not quick to burn. Making it all-or-nothing seems a bit weak to me. And the blackened appearance from burning would be due to carbon. If there is no carbon in the reaction, then there is no blackened (carbon-scored) results.
I doubt athasian silt would burn from any application of normal fire. Extremely hot fires (fireballs, lava) might beable to light it up (ie force it to break down into it's component matierals then reoxidize), but I don't think the reaction would be self sustaining.
See, I'm not certain that is completely true. Something can be able to burn, without it being able to burn well, or very fast. I don't think that the reaction will be self-sustaining as well, however I do think that Silt could potentially be able to catch fire. I'm not talking sawdust or wood here, I'm especially not talking gasoline here. I'm talking something that is a bit resiliant to fire, tends to choke out the necessary fuel (oxygen) rather quickly, and effectively will smother out the flames in a relatively short period of time. If a torch was dropped in Silt, I'm not talking an inferno here. I'm saying that the torch will burn a bit, and probably burn a little bit of the Silt around it, but like a lit match put in a jar, it will burn itself out before it does anything else. This could very easily be the results of a good portion of the composition of Silt is already oxidized, but that doesn't mean that the entirety of the Silt is non-flammable.
That huge valley of bubbling magma/lava the heat keeps the silt rolling off giving the tablelands and other nearby shores some kind of waves/ebb and flow. I mean if wind blows up a silt storm then the turbulent heat roiling off a fire would send the silt away.
I'm going with mostly burned. 2000 years of dust lightning, hot sun, sparks, etc. have given it a lot of opportunities to burn. My guess is that at the beginning of sea of silt, that silt fires were massive and common, and that now, they are small and rare. Just something to think about if someone time travels 1900 years into the past ...
I don't understand, are you disagreeing with me or not? ...Just because something can burn (is physically able to burn) that does not mean that it explodes. ...Silt, as I said, could be flammable -- as in, it is capable of being burned. However, it could need some extreme balance of Silt, oxygen, pressure, and I would bet temperature together in order to explode.
I was disagreeing in a long-winded way with the idea that something can be flammable but not explosive; an explosion is the side-effect of a fast-burning area, so if something can burn then it can, in theory, explode. The last sentence is correct, and I do agree with it - you do have to have an extremely fine balance of forces to cause an explosion, at least when we're talking about those started by the ignition of dust and oxygen. So, for your scenario (that the silt can burn, but it'd burn itself out), I was mostly trying to say that "yes, that would be correct, but if that can happen then an actual explosion could happen as well, and if it's possible for an explosion to happen odds are it would have done so already."
Deep in the silt, you'd most likely be lacking the oxygen necessary for the explosion. Or if you have the oxygen, the temperature to initiate the combustion probably isn't there. On the surface, you are completely lacking the pressure necessary for an explosion, however the mix of Silt and oxygen could possibly be enough to sustain a fire for a limited amount of time (until the fuel in the local area is used up enough to snuff it out)
According to this, the best combination of dust-to-oxygen for an explosion is one ounce per cubic foot, which is pretty dense (earlier on it says .02 ounces/cu. ft. restricts vision to about 3 feet...so we're talking "thick as soup" here). However, by Silt Sea standards, I'm guessing you'll have a layer at this density at any time in which there's a wind blowing (and especially when the wind is lower).
As it also mentions later on, in order to truly get an explosion (rather than a burnout) you need to be in a pressurized environment - difficult to do when you've got the sky above you. On the other hand, if a section of the silt were to explode, part of that pressure is going to be forced downwards, where it'll increase in pressure, which increases its explosiveness. Since we're already talking about a ratio of dust-to-oxygen that is pretty thick (and yet at "primary combustion ratio"), I can't imagine that there wouldn't still be enough oxygen deeper in the silt (and especially higher above it) that was still within the required ratio to explode. And, although (as that page states) you're not going to reach maximum pressure (since the force exploding upwards is going to be wasted into the air), the fact that some of the explosion will be directed downwards and sideways should continue the event over great distances. Might not result in the Silt Sea exploding all at once, but every time it settles back down, nice and full of static electricity generated from the first explosion (and subsequent roiling around in the air), it's only a matter of time before it goes *boom* again.
Your problem with the conduction sending the temperature down is that hot air expands, and thus rises. As the hot air rises, it lowers the temperature below, and tends to keep what is at a lower altitude at a cooler temperature. The sunlight would need incredible amounts of heat to affect it, which would make the air pressure actually decrease at lower altitudes, resulting int he Silt actually settling more, and the chances for explosion decreasing. Grain silos are enclosed systems with a lot of grain in a limited area, temperatures increase, but the heat escapes much more slowly, setting up a far more combustion-prone situation all around.
Good point - I had forgotten about the "nuclear winter" idea; just looked it up and I guess there was some study in the 70's that showed that pollution/airborne particulates was actually helping to stave off the Greenhouse Effect and global warming, so I officially retract that argument.
As for the silt vs silo bit, yes, that's true...but temperature doesn't matter if you've got something actively flaring up, be it a good-sized static electricity spark or an actual flame. And I doubt we're talking freezing conditions here, anyway; this is Athas after all, so "cool" is a relative term (and you can start a fire in the freezing cold anyway, just tends to be more difficult to get that first bit going is all). So although yes, this'll reduce the odds significantly, again we're looking at a "small odds, large area, long time" scenario - unless this was a billion-to-one scenario (which I don't think it is, especially given the info contained in the above link), I still propose that there would have been enough repeated explosions to make the idea of a "flamable silt sea" untenable.
I'm not a fan of the "already burned" idea -- I think that while it can burn, it is not quick to burn. Making it all-or-nothing seems a bit weak to me. And the blackened appearance from burning would be due to carbon. If there is no carbon in the reaction, then there is no blackened (carbon-scored) results.
Ash is often white. Near mass crematoriums, people have sometimes mistaken falling ash for snowflakes. Cement is burnt rock, IIRC, and that's light grey, or sometimes tan. From my experience, when I stir a campfire or a fireplace, the black stuff is usually the stuff that will catch fire again, like charcoal. The white and light grey stuff is the stuff that's burnt through and won't burn anymore.
Forgot about that, so NM on that one as well.
See, I'm not certain that is completely true. Something can be able to burn, without it being able to burn well, or very fast. I don't think that the reaction will be self-sustaining as well, however I do think that Silt could potentially be able to catch fire. I'm not talking sawdust or wood here, I'm especially not talking gasoline here. I'm talking something that is a bit resiliant to fire, tends to choke out the necessary fuel (oxygen) rather quickly, and effectively will smother out the flames in a relatively short period of time. If a torch was dropped in Silt, I'm not talking an inferno here. I'm saying that the torch will burn a bit, and probably burn a little bit of the Silt around it, but like a lit match put in a jar, it will burn itself out before it does anything else. This could very easily be the results of a good portion of the composition of Silt is already oxidized, but that doesn't mean that the entirety of the Silt is non-flammable.
The ability to "burn fast" is based on the oxygen-versus-flamability ratio; if something burns then there's a "critical ratio" (see the link from my prev. post) where it'll burn, and burn fast. If silt can burn, and you drop a torch into it, unless the torch extinguishes before it reaches the depth of silt where that "critical ratio" is, there will be a nice boom as the silt meeting that ratio explodes.
As for the "burnt match in a jar" comparison, there's a huge difference here; there is no "lid" to the silt; as long as the silt is able to move about (i.e. isn't compacted solid) there's still oxygen there, and as long as there's a route from that location to more oxygen (namely, all the silt around it) then once you've got the fire started it'll keep sucking up oxygen and burning. The "backdraft" effect, if you will. If there wasn't any oxygen present, there'd be no gaps between the silt particles and it would no longer flow - after all this isn't water we're talking about, it's the silt-plus-air combination that makes it behave as if a liquid. True, if the silt is barely flammable then you can still have it non-compacted but too low on oxygen to burn, but you've got to go through layers of silt that *does* have enough oxygen to burn first.
So, for your scenario (that the silt can burn, but it'd burn itself out), I was mostly trying to say that "yes, that would be correct, but if that can happen then an actual explosion could happen as well, and if it's possible for an explosion to happen odds are it would have done so already."
...in order to truly get an explosion (rather than a burnout) you need to be in a pressurized environment - difficult to do when you've got the sky above you.
My point exactly. There is no naturally-occuring pressurized environment where this could happen on Athas. And if it was an unnatural pressurized environment (like let's say... a spell or a psionic power accomplishing this) it would only potentially explode the location affected by that spell. Silos are pressurized environments. The Silt Sea isn't. Everything just isn't even remotely the correct configuration to make that a realistic probability. We're talking about a chance that even after tens of thousands of years, you still don't have one 100,000th of a percent chance. Maybe in a billion years or so, a small pocket (10' diameter or smaller) might pop, but that's it.
On the other hand, if a section of the silt were to explode, part of that pressure is going to be forced downwards, where it'll increase in pressure, which increases its explosiveness.
Without oxygen in the mix, rendering it inert.
Since we're already talking about a ratio of dust-to-oxygen that is pretty thick (and yet at "primary combustion ratio"), I can't imagine that there wouldn't still be enough oxygen deeper in the silt (and especially higher above it) that was still within the required ratio to explode.
There could be oxygen in the Silt deeper in. However without being able to trap the oxygen completely, when an explosion happened, it would push the oxygen further through the Silt to where it would escape away from the pressure.
And, although (as that page states) you're not going to reach maximum pressure (since the force exploding upwards is going to be wasted into the air), the fact that some of the explosion will be directed downwards and sideways should continue the event over great distances. Might not result in the Silt Sea exploding all at once, but every time it settles back down, nice and full of static electricity generated from the first explosion (and subsequent roiling around in the air), it's only a matter of time before it goes *boom* again.
Only if the Silt Sea is made of material prone to such things. If you take the Silo concept you've used, take the contents of that silo, and put it into a ditch, does the grain still have a chance to just explode? No -- the conditions just aren't right. With a Silo, the risk is there due to the grain being enclosed, gasses build up during the heat of the day, producing an increased level of pressure. So when something happens that could cause a little fire, rather than burning out, it makes the pressure get too great, and causes an explosion. Explosions are simply when the force inside a closed environment exceed the forces applied outside that environment.
As for the silt vs silo bit, yes, that's true...but temperature doesn't matter if you've got something actively flaring up, be it a good-sized static electricity spark or an actual flame. And I doubt we're talking freezing conditions here, anyway; this is Athas after all, so "cool" is a relative term (and you can start a fire in the freezing cold anyway, just tends to be more difficult to get that first bit going is all).
Temperature applies when in a sealed, pressurized environment, because it potentially can increase the pressure considerably; in a non-explosive situation, temperature simply can help cause something to burn, but it won't cause an explosion.
So although yes, this'll reduce the odds significantly, again we're looking at a "small odds, large area, long time" scenario - unless this was a billion-to-one scenario (which I don't think it is, especially given the info contained in the above link), I still propose that there would have been enough repeated explosions to make the idea of a "flamable silt sea" untenable.
I can't see how it would be anything less than a billion-to-one scenario. We're not talking "small odds" -- we're talking infantessimally small odds. There a greater chance that the Silt Sea will flood from a spontaneous typhoon on Athas than it would explode.
The ability to "burn fast" is based on the oxygen-versus-flamability ratio; if something burns then there's a "critical ratio" (see the link from my prev. post) where it'll burn, and burn fast. If silt can burn, and you drop a torch into it, unless the torch extinguishes before it reaches the depth of silt where that "critical ratio" is, there will be a nice boom as the silt meeting that ratio explodes.
See, I don't think there's enough trapped oxygen (specifically) in the Silt to allow for that. And, once in, when it starts to burn, it will suck the oxygen, sure, but that will cause the silt to compact around the fire more (since it is mostly air that is keeping the particles separated, even a little), resulting in the fire being smothered.
As for the "burnt match in a jar" comparison, there's a huge difference here; there is no "lid" to the silt; as long as the silt is able to move about (i.e. isn't compacted solid) there's still oxygen there, and as long as there's a route from that location to more oxygen (namely, all the silt around it) then once you've got the fire started it'll keep sucking up oxygen and burning. The "backdraft" effect, if you will. If there wasn't any oxygen present, there'd be no gaps between the silt particles and it would no longer flow - after all this isn't water we're talking about, it's the silt-plus-air combination that makes it behave as if a liquid. True, if the silt is barely flammable then you can still have it non-compacted but too low on oxygen to burn, but you've got to go through layers of silt that *does* have enough oxygen to burn first.
If we were dealing with a scenario where there was a pure mix of oxygen in the Silt at all levels, then yes. However, if there is anything else in the mix below the surface -- or if the Silt itself isn't 'pure', and has more non-flammable elements within it than flammable ones, then it chokes. Heck, even if the Silt was very flammable, but completely chokes out the oxygen (especially below the surface), then it still kills the flames.
FYI I ran a couple adventures on the other side of the planet on a continent where volcanoes spewed dust that somehow mixed with the rain to create a sort of cement. A few plants like bamboo continued to grow up through the cracks but the ancient buildings were all hundreds of feet beneath the surface, which continues to rise a couple inches each year as more layers of cement dry. (A Kurnan organization teleported the PCs there to find something[actually someone but that's a long story]; they didn't travel all the way there by themselves). The volcanic activity had also created some sort of psionic disturbance there where psionic creatures regained power points faster than normal, and passed their normal maximum, and if they gathered to many, they became paranoid and xenophobic. I think I still had a description and some photos of it, the Remaan continent, in the "Athasian Photography" section of my old "ur-braxa" site which is about 1/4 operational now, and I can't remember or get the password to fix it
partly reloaded here: http://p-nutt2.tripod.com/AthasianPhoto.htm
[INDENT]These just in: Some of you have asked me about the Reman continent. Currently information on Remaan is rather sparse, and time is too short for me to make a detailed account. But for what it is worth, here are my photos of Remaan's unusual geography. As you may recall, the Reman civilization was the source of the cultures that founded Tyr and Balic. The Remans were the most racially united of the nation-states; Remans included Elves, Humans, Orcs, Dwarves, and Pterrans. Thus Remaan took the brunt of Rajaat's anger -- The faraway continent of Remaan (almost opposite the globe from the pristine tower) was the only land where Rajaat personally led the attack.
Rajaat stirred up the bowels of the earth, turning Remaan into a volcanic wasteland. For weeks, volcanoes belch ash into the sky, until a few hours of rain temporarily clear the ash from the air. The ash turns into a sort of cement, and dries in the sun, creating a rough, mostly flat landscape, broken only by rough trenches and ever-belching volcanoes. The cycle repeats, so that the land is mostly flat with puddles of wet cement. {"photo"}
During the brief times when the air is clear, moss and plants, especially water lilies and bamboo clusters, thrive and grow rapidly. {"photo"}
Right is a rare shot of Remaan while the sky is clear. Usually the air is either filled with ash or with water mist. Note the gully -- earthquakes frequently shake the land and split the cement land to its foundations. Naturally, the water/cement slop of the rain tends to fill up these ravines.{"photo"}
Here is a shot taken from inside one of these ravines. Remaan contains at least one large but shallow bodyof water, although the precise borders shift along with the rest of the landscape. Although flat, Remaan's plains are at a high altitude after millenia of level after level of cement. Old volcanoes go extinct and new ones occasionally break through the ground and fathoms of cement. {"photo"}
[/INDENT]
Bear in mind I wrote that stuff a long time ago, long before Athas.org; it ain't official in any way shape or form. But I don't think that Athas has great civilizations away from the pristine continent, or the sorceror-kings would have settled those lands.
OTOH, maybe some did.
Another point is that with at least two large (tens of square miles) of exposed areas of liquid magma in the world for nearly 2000 years, one of the major sources of atmospheric dust (and thus, eventually, of silt) would be volcanic dust, which is (correct me if I'm wrong) incinerated rock.
Good point.
However I feel that you guys are all missing a major consequence here: The smell of all that burning dwarf hair would surely be toxic
You set me up and I roll out the punchlines.
Another point is that with at least two large (tens of square miles) of exposed areas of liquid magma in the world for nearly 2000 years, one of the major sources of atmospheric dust (and thus, eventually, of silt) would be volcanic dust, which is (correct me if I'm wrong) incinerated rock.
Ash is often white. Near mass crematoriums, people have sometimes mistaken falling ash for snowflakes. Cement is burnt rock, IIRC, and that's light grey, or sometimes tan. From my experience, when I stir a campfire or a fireplace, the black stuff is usually the stuff that will catch fire again, like charcoal. The white and light grey stuff is the stuff that's burnt through and won't burn anymore.
If that's the case and the silt is largely ash or ash-like substances, as opposed to flammable, post-organic material, then at best flames will scorch the silt (burning what little there is to burn) but you can't have a sustained fire, no explosions, nada. Which sounds like a good explaination to me, since that means I don't have to think about cascading silt explosions.
Xlorep - is that what your stance is, then? If so then you and I aren't even debating the "grain explosion" issue for the same reasons anymore, since I agree with Brax's idea here as well.
The issue comes down to whether or not silt is composed of a single, flammable material (in which case it can catch fire, and if it can catch fire in particulate form, it can explode), or else it's a mixture of a wee bit O' flammable matter but, for the most part, is composed of ash and other non-flammables, in which case it really isn't even burning (just scorching momentarily wherever fire is directly applied) and most definitely can't explode.See, I don't think there's enough trapped oxygen (specifically) in the Silt to allow for that. And, once in, when it starts to burn, it will suck the oxygen, sure, but that will cause the silt to compact around the fire more (since it is mostly air that is keeping the particles separated, even a little), resulting in the fire being smothered.
Bear in mind that my entire argument is, at this point at least, based on the information contained in that link I posted (since it was the best "explaination" of a grain silo explosion I could find): http://www.warren-group.com/articles/grainpartI.html . As stated in the first 2 paragraphs, "A dust explosion occurs when fine particles suspended in the air ignite and burn rapidly, causing a violent increase in pressure. In order to cause an explosion, the combustible mixture of air and dust must be contained in some type of vessel....Any time that grain is handled or moved, potentially explosive dust is generated....As it falls, dust separates out and becomes suspended in the airspace of the silo, creating an explosion hazard. "
Now, I do realize that, not being in an enclosed space, you're not going to get a movie-type (or grain silo ;)) explosion wherein a huge ball of flames and smoke flies out, engulfing the entire silt sea in a cataclysmic event - the second sentence above (and details later in that article) explain that away. However, the first sentence is really important as it points out that, just because you don't have a *silo* exploding doesn't mean you don't have an explosion - if the airborne silt ignites, and ignites rapidly, it is a type of explosion itself. A little later on the article mentions that the finer the particles, the more likely it is to explode (greater surface area over which the flame + air can burn).
Farther down it goes into details about pressure:
"The maximum explosion pressure for any one of these grain dusts is rarely reached...First, the dust must mix with air in much higher proportions than the minimum explosive limit. For maximum explosive pressure there must be enough dust to consume all available oxygen without any leftover dust. This proportion is around one ounce per cubic foot for most grains. Second, the explosive mixture must be contained in a vessel strong enough to withstand the maximum pressure."
...So no, exploding silt will never reach maximum pressure. But that doesn't mean it's not exploding.
Now here's the part that really convinces me that a chain effect could occur in the Silt Sea:
"Perhaps the most damaging property of grain dust explosions is the cascade effect. Grain dust that has settled...can be thrown into the air by a dust explosion, thus providing fuel for secondary explosions...In this way, a dust explosion can jump from room to room or from silo to silo. This is a common phenomenon in grain dust explosions. ...one of the most dangerous areas for grain dust explosions is in the bucket elevator...The grain is always in motion, so dust is constantly generated. "
In the Silt Sea you've got dust *everywhere*, but airborne as well as settled, so the moment there's any sort of explosion it's going to be creating an even larger cloud of airborne particles than whatever was originally there. True, it's still not contained in a room, but the fact that you've got such a sheer volume of airborne particles in one location makes up for that - the reason we don't see huge piles of flammable dust exploding in the real world is that, as big as they may be, there aren't many particles floating around in the wind, and those that are definitely aren't remotely at a concentration where they could collectively catch fire and thus explode. The Silt Sea is a totally different scenario - we're talking an area the size of a country filled with dust, that is described as "blotting out the sun on a windy day" due to the massive amount of particles floating around in the air. Although not contained in a room, that mimicks the *conditions* of that room that exist when the initial explosion happens, as well as the conditions that exist when the "secondary explosions" occur. Again, I admit this won't result in high-pressure explosions, and I'm no longer arguing that the Silt Sea would even spontaneously have exploded due to pressure (since I concede that isn't a factor)...but a lightning strike, fireball, or good-sized torch - namely any flame large enough to cause a "small" explosion - would still cascade.
The fact that you stated that you "don't think there's enough trapped oxygen" definitely makes a big difference in this argument - I think that there is enough, due to the size of the silt particles (...that is, if they are flammable to begin with, which I'm indirectly arguing against) and the way that the Silt Sea is described. If I didn't think there was enough air between the silt particles to allow them to burn (as opposed to simply being scorched by the flame) then I wouldn't be arguing any of this. Same thing goes for if the silt is only *barely* flammable - if it just gets scorched by a flame, but doesn't burn on its own, then it won't explode. But if your initial idea that it can catch fire and burn for a little while is true, then that means that silt is a viable fuel source and, if that's the case, my proposition that it can explode still holds true.
If we were dealing with a scenario where there was a pure mix of oxygen in the Silt at all levels, then yes. However, if there is anything else in the mix below the surface -- or if the Silt itself isn't 'pure', and has more non-flammable elements within it than flammable ones, then it chokes. Heck, even if the Silt was very flammable, but completely chokes out the oxygen (especially below the surface), then it still kills the flames.
Grain silo explosions don't require pure oxygen - the amount found in normal air is enough. Your other two points are valid, though; if there is a decent mixture of "non-silt" (and non-flammable) material below the surface, or if it becomes so thick, so quickly that there basically isn't any air available, then it'd choke. Like the last paragraph of my response above, this boils down to a difference of opinion as to what silt "is" and how it is constituted at deeper layers. My concept of the consistency of the Silt Sea is based on the descriptions we have from 2e material; namely, that the giants are able to wade through it because it is "loose" down to 10 or 20 feet, although even then these "packed trails" aren't permanent fixtures and occasionally will move or alltogether cease to exist. This, to me, sounds like someone wading through a stream that has a muddy bottom - roughly the same consistency from your waist down to the floor, at which point in time it becomes much thicker (relatively) but, on occasion, still isn't thick enough to hold your weight. If that analogy sounds good to you, then it would require that the air-to-silt ratio become lower (i.e. more silt, less air) quite gradually as opposed to quickly since, again, it's not for 10 to 20 feet down that it gets packed enough to walk on. Another analogy would be to compare it to a snow bank - when you walk on it you fall straight through with little resistance, as the weight of the snow is so little (on a flake-by-flake basis) that it doesn't "self-compact" itself easily. But once you've applied your own weight, compacting it down, it becomes "solid" enough for you to walk on...but it's a very defined line between the powder and the packed snow.
(Replying in reverse order as what Brax just said may make the rest of my replies moot)
If that's the case and the silt is largely ash or ash-like substances, as opposed to flammable, post-organic material, then at best flames will scorch the silt (burning what little there is to burn) but you can't have a sustained fire, no explosions, nada. Which sounds like a good explaination to me, since that means I don't have to think about cascading silt explosions.
Xlorep - is that what your stance is, then? If so then you and I aren't even debating the "grain explosion" issue for the same reasons anymore, since I agree with Brax's idea here as well.
I think you're having difficulty, because you might be attempting to visualize the Silt as being homogenous. I have stated, time and again, that I think it is a mix of a variety of different particles -- incinerated rock ash, actual real-world silt, defiler's ash, and dessicated organic material all could easily compose what you find in the Silt Sea. Of that, there are parts that *could* burn, and parts that are more resistant to it. The result is that while yes, overall, the Silt Sea could burn, it snuffs itself out.
As stated in the first 2 paragraphs, "A dust explosion occurs when fine particles suspended in the air ignite and burn rapidly, causing a violent increase in pressure. In order to cause an explosion, the combustible mixture of air and dust must be contained in some type of vessel....
Which makes the whole argument an open and shut case, by the very line you quoted. The Silt Sea is not a vessel to contain the Silt in. If you were arguing from the point of people holding Silt within some kind of a vessel -- like a Silo, for instance -- then your arguments would have more validity. Without it being held in some kind of a container, where pressure could build, the whole notion of the silt exploding is invalid.
Now, I do realize that, not being in an enclosed space, you're not going to get a movie-type (or grain silo ;)) explosion wherein a huge ball of flames and smoke flies out, engulfing the entire silt sea in a cataclysmic event - the second sentence above (and details later in that article) explain that away. However, the first sentence is really important as it points out that, just because you don't have a *silo* exploding doesn't mean you don't have an explosion - if the airborne silt ignites, and ignites rapidly, it is a type of explosion itself.
No, an explosion is directly the resultant of a usually violent release of energy and/or pressure. Which cannot happen unless you have some way to focus the pressure. Gunpowder lying on the ground and then lit does not explode -- it will just burn real fast (high oxidization ratio); put it in a shell casing, and you have a violent increase in pressure. Things like nitroglycerin are dangerous because they can produce a violent increase in pressure in open air -- meaning that high explosives can explode without necessarily needing a vessel to contain them in (they work off of releasing an incredible amount of energy). But I've never even remotely suggested that the Silt would be on the scale of either gunpowder or a high explosive like nitroglycerin. That's just foolishness.
"The maximum explosion pressure for any one of these grain dusts is rarely reached...First, the dust must mix with air in much higher proportions than the minimum explosive limit. For maximum explosive pressure there must be enough dust to consume all available oxygen without any leftover dust. This proportion is around one ounce per cubic foot for most grains. Second, the explosive mixture must be contained in a vessel strong enough to withstand the maximum pressure."
Once again, it must be contained in a vessel. The Silt Sea is not a vessel. It is open to the atmosphere, which then means that you'd have to build that much pressure without a vessel, and you'd have to have something that is a high explosive.
"Perhaps the most damaging property of grain dust explosions is the cascade effect. Grain dust that has settled...can be thrown into the air by a dust explosion, thus providing fuel for secondary explosions...In this way, a dust explosion can jump from room to room or from silo to silo. This is a common phenomenon in grain dust explosions. ...one of the most dangerous areas for grain dust explosions is in the bucket elevator...The grain is always in motion, so dust is constantly generated. "
From container to container. Sorry, but if you had that grain dumped out in a lake bed, and it filled the lake bed, and some of the grain dust was around, it wouldn't explode.
In the Silt Sea you've got dust *everywhere*, but airborne as well as settled, so the moment there's any sort of explosion it's going to be creating an even larger cloud of airborne particles than whatever was originally there. True, it's still not contained in a room, but the fact that you've got such a sheer volume of airborne particles in one location makes up for that - the reason we don't see huge piles of flammable dust exploding in the real world is that, as big as they may be, there aren't many particles floating around in the wind, and those that are definitely aren't remotely at a concentration where they could collectively catch fire and thus explode.
Without it being in a container that can actually assist with building up the pressure, you do not have an explosion. Period. If you can't get the pressure, there is no explosion. It simply burns, and eventually will burn out. Massive forest fires would leave huge impact craters where trees that were burning spontaneously exploded as well, if the pressure is not important.
The Silt Sea is a totally different scenario - we're talking an area the size of a country filled with dust, that is described as "blotting out the sun on a windy day" due to the massive amount of particles floating around in the air. Although not contained in a room, that mimicks the *conditions* of that room that exist when the initial explosion happens, as well as the conditions that exist when the "secondary explosions" occur. Again, I admit this won't result in high-pressure explosions, and I'm no longer arguing that the Silt Sea would even spontaneously have exploded due to pressure (since I concede that isn't a factor)...but a lightning strike, fireball, or good-sized torch - namely any flame large enough to cause a "small" explosion - would still cascade.
There isn't enough pressure. Without pressure, it isn't an explosion. I don't quite know how else to explain it to you. Even the article you keep linking states, rather succinctly and clearly that you need pressure for the explosion. It also rather clearly states that with grain explosions (in particular), it needs to be contained in some vessel. You can't even have a "small" explosion unless you can have the pressure for it. Normal atmospheric pressures don't help, because the air simply escapes all over the place. High Explosives still follow the same pattern, but need considerably less pressure to accomplish the goal. But we're not talking about anything in the area code of a high explosive. We're not talking about anything in the area code of a 'low explosive' like gunpowder. We're talking about the Silt Sea... which even the grain analogy is imperfect, because the grain is homogenous.
The fact that you stated that you "don't think there's enough trapped oxygen" definitely makes a big difference in this argument - I think that there is enough, due to the size of the silt particles (...that is, if they are flammable to begin with, which I'm indirectly arguing against) and the way that the Silt Sea is described. If I didn't think there was enough air between the silt particles to allow them to burn (as opposed to simply being scorched by the flame) then I wouldn't be arguing any of this. Same thing goes for if the silt is only *barely* flammable - if it just gets scorched by a flame, but doesn't burn on its own, then it won't explode. But if your initial idea that it can catch fire and burn for a little while is true, then that means that silt is a viable fuel source and, if that's the case, my proposition that it can explode still holds true.
Actually, your proposition isn't true. It doesn't hold to laws of physics or chemistry. It just doesn't work. If we were talking about the silt being held in some sort of a container that can contain the initial pressure, then sure. Your argument would be stronger. But we're talking about something that is open to the sky, blows in the wind constantly, and has no way to naturally achieve the pressure requirements to explode, unless it was helped artifically though magic or psionics. The burnability of something does not determine an explosion. The pressure determines explosions. Things don't even need to burn to explode. A balloon, for instance, if it is given too much air, the pressure exceeds the threshold of the material that the balloon is made of, and it explodes. That has absolutely nothing to do with whether or not the material can or cannot burn. It has everything to do with pressure.
Grain silo explosions don't require pure oxygen - the amount found in normal air is enough.
Grain silo explosions deal with something contained within a vessel that allows for the buildup of pressure. Without that, then you'd need to 'help it' be able to explode somehow.
Like the last paragraph of my response above, this boils down to a difference of opinion as to what silt "is" and how it is constituted at deeper layers. My concept of the consistency of the Silt Sea is based on the descriptions we have from 2e material; namely, that the giants are able to wade through it because it is "loose" down to 10 or 20 feet, although even then these "packed trails" aren't permanent fixtures and occasionally will move or alltogether cease to exist. This, to me, sounds like someone wading through a stream that has a muddy bottom - roughly the same consistency from your waist down to the floor, at which point in time it becomes much thicker (relatively) but, on occasion, still isn't thick enough to hold your weight. If that analogy sounds good to you, then it would require that the air-to-silt ratio become lower (i.e. more silt, less air) quite gradually as opposed to quickly since, again, it's not for 10 to 20 feet down that it gets packed enough to walk on. Another analogy would be to compare it to a snow bank - when you walk on it you fall straight through with little resistance, as the weight of the snow is so little (on a flake-by-flake basis) that it doesn't "self-compact" itself easily. But once you've applied your own weight, compacting it down, it becomes "solid" enough for you to walk on...but it's a very defined line between the powder and the packed snow.
We have no difference of opinion on what the Silt Sea consists of. The difference of opinion is that you think that by virtue of something being burnable, it therefore must explode. My view (which is backed by science) is that in order for something to explode, there must be a violent release of pressure. If there is no pressure change, there is no explosion. Plain and simple.
ex·plo·sion Pronunciation Key (k-splzhn)
n.
1.
1. A release of mechanical, chemical, or nuclear energy in a sudden and often violent manner with the generation of high temperature and usually with the release of gases.
2. A violent bursting as a result of internal pressure.
3. The loud, sharp sound made as a result of either of these actions.
None of those situations apply to the notion that the Silt Sea can burn. The first is a release of energy, often violent. There is none of that involved by virtue of whether the Silt Sea can burn or not. For there to be a violent bursting as a result of internal pressure, there must first actually be internal pressure. Which is not the case, and has nothing to do with whether or not the Silt Sea can burn.
I think you're having difficulty, because you might be attempting to visualize the Silt as being homogenous. I have stated, time and again, that I think it is a mix of a variety of different particles -- incinerated rock ash, actual real-world silt, defiler's ash, and dessicated organic material all could easily compose what you find in the Silt Sea. Of that, there are parts that *could* burn, and parts that are more resistant to it. The result is that while yes, overall, the Silt Sea could burn, it snuffs itself out.
As it stands now I don't think it's homogenous, and that, except for the last sentence, the rest of the above is correct. My original "grain silo explosion" statement was posted before you had made any statements, and up until that point everyone was arguing simply pro/con silt (as a whole) being able to burn. Your first post suggested that silt could somehow burn but that it would "put itself out" due to filling in on itself and the smoke, to which I replied "okay I guess that could happen on the surface, but otherwise you're getting back into an explosion-type scenario" and it sorta snowballed from there away from the original debate/question. The idea of it being mostly non-flammables with a small amount of flammable material mixed in came much later, which is why I started my last post with the "...this may be moot" statement - as a mixture, nothing I said regarding explode-ability counts - that'd require that it *all* (or quite a bit, at least) be flammable material.
Although now I don't agree with even a surface fire "burning itself out" idea - wildfires are extremely smokey, not everything in the area is flammable (they're sitting on ground, after all) and yet they don't "suffocate" themselves, so if the silt had any quantity of flamable substance in it I don't see why it'd spread in a similar fashion. If it's just a tiny bit of burnable stuff here or there then you'd get some smoke and that'd be about it, but if there's enough burnable materials present than any silt that spilled into the burning area would itself catch fire.
No, an explosion is directly the resultant of a usually violent release of energy and/or pressure.
Actually, as you point out later, an explosion isthe violent release of energy and/or pressure, not the result of that. That differentiation will make a difference a little later in this reply.
Gunpowder lying on the ground and then lit does not explode -- it will just burn real fast (high oxidization ratio); put it in a shell casing, and you have a violent increase in pressure.
By the first dictionary.com definition, the gunpowder burning quickly is a form of explosion - it's the release of chemical energy accompanied by a high temperature and release of gases. In a shellcasing it meets both the #1 and #2 definitions. But a pile of quickly-burning gunpowder still is an 'explosion', it's just not the huge-ball-of-fire-and-smoke-with-a-big-shockwave type of explosion.
Things like nitroglycerin are dangerous because they can produce a violent increase in pressure in open air -- meaning that high explosives can explode without necessarily needing a vessel to contain them in (they work off of releasing an incredible amount of energy). But I've never even remotely suggested that the Silt would be on the scale of either gunpowder or a high explosive like nitroglycerin. That's just foolishness.
No arguments there; nitro and other high-explosives are dangerous because of how quickly they burn, how much gas is released, and the overall shockwave that creates.
As for silt exploding like gunpowder or nitro, I agree that's silly, and I thought I'd stated awhile back that I wasn't arguing for that (anymore, at least...initially I was thinking it, I'll admit).
Once again, it must be contained in a vessel. The Silt Sea is not a vessel. It is open to the atmosphere, which then means that you'd have to build that much pressure without a vessel, and you'd have to have something that is a high explosive.
Now the issue is with your perception of me saying "the silt would explode" and what I'm suggesting by it. The dictionary.com definition of "explosion" supports the idea that, even without a silo to contain it, if you got a cloud of grain dust floating in a dense cloud *anywhere* you could make it explode - it'd be a short-lived, not very impressive explosion, but by the #1 definition of 'explosion' it would still constitute one. So if silt, as a whole (homogenous or not) had an equivalent capability to burn, it too could 'explode'.
Massive forest fires would leave huge impact craters where trees that were burning spontaneously exploded as well, if the pressure is not important.
When a bunch of trees burn, it constitutes an explosion of sorts - again, not a big-boom-everyone-dies type, but it is a violent, hot, chemical reaction. Since the pressure created is so minimal it takes wind to fan the flames elsewhere, but again, by the definition of 'explosion' you posted this still is one. But no, there are no craters.
The burnability of something does not determine an explosion. The pressure determines explosions. Things don't even need to burn to explode. A balloon, for instance, if it is given too much air, the pressure exceeds the threshold of the material that the balloon is made of, and it explodes. That has absolutely nothing to do with whether or not the material can or cannot burn. It has everything to do with pressure.
...but only if you're defining an 'explosion' as "the violent release of pressure" which I'm not trying to do. The quickness with which something burns *does* determine how well it explodes, and the act of burning is itself a type of explosion (again, see your posted definition). Without the container we're not going to get a pressure-explosion, but we can still get a wildfire-like firestorm 'explosion.'
We have no difference of opinion on what the Silt Sea consists of. The difference of opinion is that you think that by virtue of something being burnable, it therefore must explode. My view (which is backed by science) is that in order for something to explode, there must be a violent release of pressure. If there is no pressure change, there is no explosion. Plain and simple.
Heh but the definition you just posted goes against this - it says that the violent release of pressure is a secondary definition of "an explosion" and not the first. A chemical reaction involving the violent release of heat and gases doesn't occur *because* of pressure (well, not normally at least), it *results* in pressure. So yes, there is a pressure change - when the gas is released - but in the case of something burning that occurs *after* it's already 'exploded'.
None of those situations apply to the notion that the Silt Sea can burn. The first is a release of energy, often violent. There is none of that involved by virtue of whether the Silt Sea can burn or not. For there to be a violent bursting as a result of internal pressure, there must first actually be internal pressure. Which is not the case, and has nothing to do with whether or not the Silt Sea can burn.
You're mixing the 1st and 2nd definitions into a single entity, which is incorrect and causing problems here as I'm not arguing for the second anymore - I'm (now) only arguing that if a high enough concentration of the mixed materials that makes up 'silt' is flammable, to the point where this 'silt mixture' could sustain a fire for any length of time, then if you get a bunch of it airborne you can create a chemical explosion (i.e. a bunch of it burning nearly simultaneously, creating an outward expansion of heat and pressure beyond what was there prior to it burning, and in turn possibly causing additional 'explosions'). Again, we're not starting with the pressure, we're ending with it.
As a side-note, when a grain silo explodes (i.e. blows itself all over the place in a big fireball), it starts with a chemical reaction (fire + oxygen + flammable substance; the grain), which releases gas and pressure, which ignites nearby grain + oxygen, which in turn creates more pressure and gas, until the entire silo builds up too much pressure and ruptures in the fashion you're describing. But it's not starting with the pressure - it's starting with a simple mix of flammable, airborne particles and flame.
I think you're having difficulty, because you might be attempting to visualize the Silt as being homogenous. I have stated, time and again, that I think it is a mix of a variety of different particles -- incinerated rock ash, actual real-world silt, defiler's ash, and dessicated organic material all could easily compose what you find in the Silt Sea. Of that, there are parts that *could* burn, and parts that are more resistant to it. The result is that while yes, overall, the Silt Sea could burn, it snuffs itself out.
I don't think either Dirk or I said that it was homogeneous; we were talking about the sea in general. I think it's quite likely that a large mud patch might lose a water source, dry up into silt, leaving you with an area that was quite flamable. Another patch of silt might be the focal point of winds that blow across the land, so that fresh organic dust gets deposited in an area, allowing brief brief flash surface fires.
I'm just saying that any flammable silt that's been silt for thousands of years, is going to have burned already. I think we all agree that the sea, as one cohesive body, isn't going to go up in some massive conflagration. However such a thing *might* have happened, 1800+ years ago, early in the time of the sea of silt, contributing to the browning of an already badly damaged planet.
I don't think either Dirk or I said that it was homogeneous; we were talking about the sea in general. I think it's quite likely that a large mud patch might lose a water source, dry up into silt, leaving you with an area that was quite flamable. Another patch of silt might be the focal point of winds that blow across the land, so that fresh organic dust gets deposited in an area, allowing brief brief flash surface fires.
Which is basically exactly what I was getting at by saying that it is able to burn. There is a mix of a variety of things in the silt, and some of that mix will burn. Will it sustain itself? No. But it can burn for a short period as the fuel gets all used up. Even if it just blackens, then that would mean technically it burns.
Dirk's direction was (from what I was seeing) to take the slippery slope of 'if it is able to burn, therefore the Sea of Silt would explode' -- relying on information about Silo explosions, which is not really applicable due to a completely different and mutually exclusive set of conditions. He's modified it a bit now, and I think we're arguing two sides of the same coin at this point.
I'm just saying that any flammable silt that's been silt for thousands of years, is going to have burned already. I think we all agree that the sea, as one cohesive body, isn't going to go up in some massive conflagration. However such a thing *might* have happened, 1800+ years ago, early in the time of the sea of silt, contributing to the browning of an already badly damaged planet.
I'd say that for the most part... you might be right. The parts that have been silt for thousands of years and could be burned, most likely have been burned. The parts that haven't, would be things that are not exposed to the right conditions -- deep Silt and all of that. The surface of the Silt Sea would be prone to a little bit more burning, as it has quite a bit of 'impurities' -- particles that have not been Silt for thousands of years. Those elements could contain a noticeable amount of particles that could be burned -- moreso in certain clumped patches like you explained, but even in the wide open 'typical' Sea of Silt conditions, there would be a good chance that some of it will burn, like I said, for a round or two (at most), before it burns itself out.
Dirk's direction was (from what I was seeing) to take the slippery slope of 'if it is able to burn, therefore the Sea of Silt would explode' -- relying on information about Silo explosions, which is not really applicable due to a completely different and mutually exclusive set of conditions. He's modified it a bit now, and I think we're arguing two sides of the same coin at this point.
Originally yes, that's what I was saying, from the extremist standpoint that everything that was silt was flammable and not just parts of it. Having conceded that no one thinks that, then agreed, I think at this point our argument is a side-line debate to the original question of "can silt burn?"
but that, when it comes down to answering that question we're in agreement ("Yes, depending on local conditions.")
I'm just saying that any flammable silt that's been silt for thousands of years, is going to have burned already. I think we all agree that the sea, as one cohesive body, isn't going to go up in some massive conflagration. However such a thing *might* have happened, 1800+ years ago, early in the time of the sea of silt, contributing to the browning of an already badly damaged planet.
I'd say that for the most part... you might be right. The parts that have been silt for thousands of years and could be burned, most likely have been burned. The parts that haven't, would be things that are not exposed to the right conditions -- deep Silt and all of that. The surface of the Silt Sea would be prone to a little bit more burning, as it has quite a bit of 'impurities' -- particles that have not been Silt for thousands of years. Those elements could contain a noticeable amount of particles that could be burned -- moreso in certain clumped patches like you explained, but even in the wide open 'typical' Sea of Silt conditions, there would be a good chance that some of it will burn, like I said, for a round or two (at most), before it burns itself out.
Something else to consider here: given that the Silt Sea came into existence during two millenia of war, a war in which defilers were rampant - when and where they had a source of plant life to draw energy from - what are the odds that the Silt Sea ever had enough of a "tinder build-up" for more than a minor fire to spring up at any given time? The closest example I can think of would be what happens to a pond during a drought - as it shrinks the organic materials in the water tend to become more concentrated, while the heavier organic materials are left behind. Of those that are left behind, any water plants are either eaten by animals or dry up and eventually are blown away (either back into the receding water or elsewhere), while the rest forms a sort of "organic mud" that sits on the surface. Eventually you end up with a clump of organic goo in the center of the dried-up lake, and a bunch of less-organic clay that gets "thinner" the farther from the center you get.
With defilers thrown into the equation, however - especially since they were (I'm assuming) a major contributor to the Silt Sea's creation - there would be no organic material left behind as the sea dried up as every time a defiler cast a spell near the water, all the organic material-sediment currently there gets killed right along with whatever happens to be in the water. In areas where the sea receded but there was no direct defiler use, the organic material there would likely have been eaten up by grass, spawning grasslands. Once you've got grasslands along the edge of a receding sea, however, you've got lightning-induced (or man-made) wildfires to worry about; that grass would have enough time to grow up, but by the time anything larger than a small tree was well-rooted the water would have retreated far enough away that it'd turn into the perfect wildfire breeding ground. And, of course, if it did somehow survive wildfires, there's still those damned wizards trying to find some plantlife to soak up energy from.
Something else to consider here: given that the Silt Sea came into existence during two millenia of war, a war in which defilers were rampant - when and where they had a source of plant life to draw energy from - what are the odds that the Silt Sea ever had enough of a "tinder build-up" for more than a minor fire to spring up at any given time? The closest example I can think of would be what happens to a pond during a drought - as it shrinks the organic materials in the water tend to become more concentrated, while the heavier organic materials are left behind. Of those that are left behind, any water plants are either eaten by animals or dry up and eventually are blown away (either back into the receding water or elsewhere), while the rest forms a sort of "organic mud" that sits on the surface. Eventually you end up with a clump of organic goo in the center of the dried-up lake, and a bunch of less-organic clay that gets "thinner" the farther from the center you get.
Something I have considered... When a defiler actually defiles, what is left is defiler's ash. Which means that basically, something happened to the water contained in the plants (or for a dragon, animals). If we play 'apply scientific explanations' to things... the checmical bonds for the water could have been destroyed, rebonding it to H2 and O2 molecules -- effectively vaporizing the plant in question (releasing physical energy that could be related to that extra 'oomph' that the defilers tend to get). What is left would be dessicated, potentially charred remains, like ashes, of the victim. It doesn't explain how that becomes toxic to the environment, but it is a 'scientific' idea as to what much of defiler's ash consists of. Working with this, if a defiler was to strip plants that are actually in bodies of water at the time, the defiler could effectively destroy quantities of that surrounding water with their actions, resulting in the water being changed to hydrogen and oxygen as well, and the sea level being reduced, even slightly. Not only are they effectively destroying the water, but also adding that dessicated remains, 'defiler's ash' to the water, which could eventually settle to the bottom, forming a thick mud -- possibly one of the main components of the real-deep Silt.
Add in another possibility... what if the Rhulisti weren't 100% successful at wiping out the Brown Tide. It tends to be something like an algae or bacterium that devours water (maybe breaking it into hydrogen & oxygen) -- which the actions of the defilers could have made the Brown Tide algae reproduce and expand faster, devouring the oceans (what if it actually fed on defiler's ash as well?). The algae grows rapidly, batches of it become dessicated into defiler's ash during the cleansing wars, only to be effectively used as fertilizer to spawn more of the Brown Tide algae. Once the oceans got too low, the algae begins to die when dried out, and after a number of years, breaks down into silty particles as well. Tack on eroded earth minerals, and a good supply of volcanic ash, what do you have? A ton of dust billowing around in the dried basins of the seas and oceans.
Of that stuff.... I'd say that any of the remains of the algae could potentially be able to burn. I'm not entirely certain if the defiler's ash could be burned, and the eroded minerals (fine-grained sand, etc.) wouldn't exactly be necessarily burnable. The volcanic ash would have already been burned quite a bit. As Brax mentioned earlier.. there's some rather large open lava vents and cracks on the surface of Athas... think about how much ash could be spewing out from those over thousands of years.
I was thinking along the same lines re: defiling and water, just didn't specifically state it as such. Never really thought about tying the brown tide into it, but I don't think anyone would have noticed it that had happened. To most, it would just appear as if the sea was becoming polluted, and given that there was a huge war going on it's not like most people would have worried much about it.
Interesting possibility.
Organic matter is probably the only thing with a low enough burning point that it'd be an issue in the Silt Sea - although you can get metals and other minerals to burn, the temperature tends to be so high that it wouldn't really be applicable here.
I was thinking along the same lines re: defiling and water, just didn't specifically state it as such. Never really thought about tying the brown tide into it, but I don't think anyone would have noticed it that had happened. To most, it would just appear as if the sea was becoming polluted, and given that there was a huge war going on it's not like most people would have worried much about it.
Interesting possibility.
Well, the oceans disappearing, and the lore/history pointing to early on, there being some sort of a lifeshaping accident that was destroying the oceans, seems like more than a coincidence. If the Pristine Tower had destroyed much of the Brown Tide, but some of it was more or less in 'recession', or 'hibernation', but that was reactivated through the careless use of defiling magic during the Cleansing Wars, then it can help explain some of the reaspons the water is gone, and possibly what a good chunk of the Silt is comprised of. Mind you, I don't think *all* the water went away like that, I also think that the unprecidented growth of the Sun (thanks to Rajaat) had to set some serious tectonic effects and events into motion, cracking the surface, and a good amount of the water also went into those cracks, forming underground resevoirs.
I think that the biggest single shock that the oceans ever received was Quith's little mistake, the Dark Tide, some call it, while others call it the Shining Tide, depending on what angle they stood from the sun during their last moments of life. (Amazing how talkative dead people are down in the Dead Lands) Spill a few billion gallons of molten obsidian into the oceans, and my guess is that the overall ocean temperature is going to go up, somewhat. If Athas had ice caps, that might have absorbed some edge of the shock to the oceans' equilibrium, but my guess is that the obsidian incident is when most plants and animals in the sea died or started to die.
I'm no geologist, but of the little I know about currents, if the oceans didn't come to a boil all at once, then there were probably at least boiling and scalding currents shooting long ways across the deep. Fishermen scalded alive out of nowhere on the other side of the planet.
[INDENT]161st King's Age (-2,233)
Friend's Reverence: Far South of Balic, an accident of unknown origins opens a gate to the Inner Planes, and obsidian flows across the land for hundreds of miles in each direction until the gate is closed by the Seventh Tree. Thousands die in the disaster. Those killed by the obsidian wave rise as undead. The Dead Lands are born. The world’s oceans boil as they come into contact with cubic miles of liquid obsidian. Keltis sees the Dead Lands, soon after their formation, and is horrified at what he finds there. By magically interrogating undead captured at the edge of the devastation, Keltis learns that the obsidian wasteland was Rajaat’s doing. Disgusted by the complete ruin of the Starlight Sea, Keltis nonetheless feels obligated to complete his task.[/INDENT]
(Is bringing the world's oceans to a boil an exaggeration, looking at the maps at the sheer volume of obsidian that poured into them?
If there were any brown tide, the obsidian cataclysm might have finished it off -- or might have reawakened it from dormancy. E.g. perhaps the pristine tower had been used to create some organism that kept the brown tide at bay, and the obsidian cataclysm destroyed that organism, rereleasing brown tide.
Volcanic as is indeed a lot of non-flammable stuff in the sea of silt. Might even make up a majority, today. That could explain the mystery of how the sea of silt has risen (other than the mystical explanation of some victory in the elemental planes, that is: I have no problem with having parallel mystical and physical explanations for the same thing -- I don't know if that's because I'm storyteller or because I'm a religious heretic.)
But my guess is that those horrid exposed magma strips did not exist in the Green Age, or during most of the cleansing wars. I still think that during the first months or years of the sea of silt, that there were some very large and scary fires, perhaps even a planet-wide fire.
Consequently ... so what?
- Well, one might find some interesting scrags. Water and rain priests burnt alive while on the sea of silt or in a mud flat. (Would a water or rain priest turn into a scrag if boiled or scalded alive by steam, as probably happened during the obsidian cataclysm? There might be ghost ships of scalded creatures roaming the silt, but that's not part of this burnt silt idea)
- PCs might encounter ancient coastal and underwater cities destroyed by fire.
- PCs might run into areas that were somehow shielded from fire, e.g. like the rooms in city by the silt sea where there was no oxygen. Some former underwater city with a great dome, for example, and no air. The tip of the dome breaks the surface of the silt. PCs break the dome to bring in the air, so they can explore the dome. Dandy, but then they'd better be careful of using fire in there against the dry desicated undead creatures they find there. The city and the silt have sat dry and unlit for King's Ages and could go up like a torch.
- PCs might just run into ancient written references to the event, or paintings or carvings that show it; it might do nothing for the adventure other than add color. Or, if they got to Kurn, there are scholars in the Great Library that would actually pay good money for ancient scrolls that contained such incredibly obscure information, so it's a treasure reward, if the PCs can figure out how to collect on it.
- Some meorty on the coast might have the event stuck in his head, and have an insane fixation about preventing anyone from lighting or bringing fire near the silt. This obviously would not be one of the original rules of the Meorty, but my guess is that they were adaptive thousands of years ago before they went senile. Could even be a nice meorty, who is very helpful unless you do that one thing, and then she kills you, sorrowfully warning the others that the silt catches fire. (which it doesn't, anymore.)
Can anyone think of any other effects, today, of the silt once having been flammable, or of raging silt fires that occured 1800+ years ago?
I agree that defilers are a major contributor to the state of the planet, but I don't think for a second that defiling ash is more than a very small fraction of the sea of silt. Defilers go for the most fertile areas to gather power, and they knock holes in the general web of life ... often fatally to a wider ecosystem. When an area turns to desert, most of it is going to be initially flammable.
I don't think for a second that defiling as is more than a very small fraction of the sea of silt either. I'm just suggesting that it could have 'woken up' remnants of the Brown Tide that wracked Athas at the end fo the Blue Age. The very same Brown Tide that was noted for destroying (consuming) the oceans, and most likely was the event that forced the Rhulisti to transform themselves into various other races with no memories (or apparent understanding) of how to lifeshape.
I think that the biggest single shock that the oceans ever received was Quith's little mistake, the Dark Tide, some call it, while others call it the Shining Tide, depending on what angle they stood from the sun during their last moments of life. (Amazing how talkative dead people are down in the Dead Lands) Spill a few billion gallons of molten obsidian into the oceans, and my guess is that the overall ocean temperature is going to go up, somewhat. If Athas had ice caps, that might have absorbed some edge of the shock to the oceans' equilibrium, but my guess is that the obsidian incident is when most plants and animals in the sea died or started to die.
That could very well be a hugr contributer. Quith's mistake, Rajaat's effects on the sun, and rampant, careless use of defiling magic across the known world during the Cleansing Wars all probably had some incredible ecological impacts to the world. The Brown Tide reemerging would have slipped by somewhat unnoticed by any historians at the time, for a) they probably wouldn't know what it was, and b) there was more than a few other things going on at the time as well.
I'm no geologist, but of the little I know about currents, if the oceans didn't come to a boil all at once, then there were probably at least boiling and scalding currents shooting long ways across the deep. Fishermen scalded alive out of nowhere on the other side of the planet.
Good point. The oceans could have quickly become extraordinarily deadly to anyone near them.
161st King's Age (-2,233)
Friend's Reverence: Far South of Balic, an accident of unknown origins opens a gate to the Inner Planes, and obsidian flows across the land for hundreds of miles in each direction until the gate is closed by the Seventh Tree. Thousands die in the disaster. Those killed by the obsidian wave rise as undead. The Dead Lands are born. The world’s oceans boil as they come into contact with cubic miles of liquid obsidian. Keltis sees the Dead Lands, soon after their formation, and is horrified at what he finds there. By magically interrogating undead captured at the edge of the devastation, Keltis learns that the obsidian wasteland was Rajaat’s doing. Disgusted by the complete ruin of the Starlight Sea, Keltis nonetheless feels obligated to complete his task.
That would be a crappy task Keltis had to perform.
(Is bringing the world's oceans to a boil an exaggeration, looking at the maps at the sheer volume of obsidian that poured into them?
I'd believe that they boiled. The problem however is that once boiled, they get into the atmosphere. In the atmosphere the excess heat would cool off (especially on the night side of Athas), and then you'd end up with clouds & rain. Boiling is a great thing to consider, but it isn't the lone thing responsible for the disappearance of the oceans completely.
If there were any brown tide, the obsidian cataclysm might have finished it off -- or might have reawakened it from dormancy. E.g. perhaps the pristine tower had been used to create some organism that kept the brown tide at bay, and the obsidian cataclysm destroyed that organism, rereleasing brown tide.
I like that line of thinking. Even more than tying it to defilers directly. If the obsidian caticlysm destroyed whatever means the pristine tower was using to keep the brown tide at bay... then even after the water would being to fall back to the ground, it would have to contend with the re-emerged Brown Tide.
Volcanic as is indeed a lot of non-flammable stuff in the sea of silt. Might even make up a majority, today. That could explain the mystery of how the sea of silt has risen (other than the mystical explanation of some victory in the elemental planes, that is: I have no problem with having parallel mystical and physical explanations for the same thing -- I don't know if that's because I'm storyteller or because I'm a religious heretic.)
But my guess is that those horrid exposed magma strips did not exist in the Green Age, or during most of the cleansing wars. I still think that during the first months or years of the sea of silt, that there were some very large and scary fires, perhaps even a planet-wide fire.
I'm sure that it would seem to the vast majority of the people in those times, like the end of the world was upon them.
Can anyone think of any other effects, today, of the silt once having been flammable, or of raging silt fires that occured 1800+ years ago?
not particularly off hand.
I don't think for a second that defiling as is more than a very small fraction of the sea of silt either. I'm just suggesting that it could have 'woken up' remnants of the Brown Tide that wracked Athas at the end fo the Blue Age. The very same Brown Tide that was noted for destroying (consuming) the oceans, and most likely was the event that forced the Rhulisti to transform themselves into various other races with no memories (or apparent understanding) of how to lifeshape.
See, the no memory thing makes me think that the rhulisti that remained halflings, were at least partly in control of the process. If you were going to switch species and lose your memory, wouldn't you leave info and gear for yourself? Have your nice halfling family and friends explain it to you, give you great lifeshaped stuff to build your new life? There's something dark going on there. Halflings are generally speaking incredibly racist. There had to be something odd about who changed, and who remained rhulisti.
[INDENT]That could very well be a hugr contributer. Quith's mistake, Rajaat's effects on the sun, and rampant, careless use of defiling magic across the known world during the Cleansing Wars all probably had some incredible ecological impacts to the world. The Brown Tide reemerging would have slipped by somewhat unnoticed by any historians at the time, for a) they probably wouldn't know what it was, and b) there was more than a few other things going on at the time as well.[/INDENT]
Even if it was a critical driving effect, I can't imagine how anyone could reasonably have known about what was going on beneath the waves and muck of the dead sea.
[INDENT]I'd believe that they boiled. The problem however is that once boiled, they get into the atmosphere. In the atmosphere the excess heat would cool off (especially on the night side of Athas), and then you'd end up with clouds & rain. Boiling is a great thing to consider, but it isn't the lone thing responsible for the disappearance of the oceans completely.[/INDENT]
I'm not so sure. The heat doesn't just go away; the world is hotter. The rains come down, but not right into the ocean. Massive flooding and erosion as half of the ocean comes crashing down at once from the sky. Huge swaths of land are dragged down into the sea. Whatever survived the initial boil now has to deal with a massive change in salinity, mineral composition, and opaqueness. It doesn't explain how *all* the water went away, but explains how so much dust and gunk got into it. Maybe the water didn't go away; maybe lots of the original oceans are trapped beneath the surface, beneath hard layers of mud beneath the silt. Or maybe we have to go mystical at some point (thinking back to Rajaat turning the sun blue and bringing water back... then shakes head, since that's just too ... easy)
[INDENT]I like that line of thinking. Even more than tying it to defilers directly. If the obsidian caticlysm destroyed whatever means the pristine tower was using to keep the brown tide at bay... then even after the water would being to fall back to the ground, it would have to contend with the re-emerged Brown Tide.[/INDENT]
Again we get back to the so what question. How does this affect the PCs now? What exactly does brown tide do? I guess someone could use it to destroy the last sea, but why? Mad silt cleric? TOO James Bond, IMO.
OTOH, maybe some sort of Brown Tide bomb, if PCs could cultivate it, might plug up the Cerulean storm, and end the Tyr-Storms. Or maybe at least some wacky sage might tell them that would be the effect, and hard to tell whether it would work until you tried it.
Although ... Does the cerulean storm actually bring water into Athas from the *outside*, i.e. planes of water and air?
[INDENT]
I'm sure that it would seem to the vast majority of the people in those times, like the end of the world was upon them.[/INDENT]
It *was* the end of that world. Poor Athas has ended many times, and each time a less glorious world has been reborn upon its ashes.
Even if it was a critical driving effect, I can't imagine how anyone could reasonably have known about what was going on beneath the waves and muck of the dead sea.
Who said anything about anyone reasonably knowing what was going on beneath the waves? why do people in the world need to know the exact cause of the loss of water? I was merely providing another avenue to explain why some of the water is gone.
Again we get back to the so what question. How does this affect the PCs now? What exactly does brown tide do? I guess someone could use it to destroy the last sea, but why? Mad silt cleric? TOO James Bond, IMO.
Why does it have to affect the PCs now? Why can't it be part of the event that resulted in the permanent loss of the oceans? See.... laws of matter & energy conservation would mean that the water would have had to go somewhere. Unless we're saying it got all shunted to the Plane of Water, it went somewhere on Athas, right? Water in the air would be water vapor. The water gets to the night side of Athas, where it is in fact cooler, considerably cooler, and you'd have clouds and rain happening. If the heat from the Sun is enough to dehydrate and evaporate that water during the day, then I think we'd have to reconsider the climate of Athas a bit -- because that's not just hot... that's damned hot. That means it gets over 100 degrees celsius every day. People really wouldn't be alive.
OTOH, maybe some sort of Brown Tide bomb, if PCs could cultivate it, might plug up the Cerulean storm, and end the Tyr-Storms. Or maybe at least some wacky sage might tell them that would be the effect, and hard to tell whether it would work until you tried it.
I personally think that by now, the Brown Tide is definitely dead. What we know of the stuff is it consumed water. Without there being water left on the surface of Athas, the Brown Tide would most likely be dead, or maybe in hibernation somewhere.
Although ... Does the cerulean storm actually bring water into Athas from the *outside*, i.e. planes of water and air?
I'd think not from planes of water and air, but the plane of rain. Rain is the most hard-up of the paraelements, and could have seen an alliance with Rajaat as a good thing for it. Or if you don't like that theory, Rajaat had been studying the inner planes for a while, and could have gained mastery over parts of the plane of rain.
Who said anything about anyone reasonably knowing what was going on beneath the waves?
Someone was saying something about sages knowing about it. Maybe I misunderstood.
[INDENT]Why does it have to affect the PCs now? Why can't it be part of the event that resulted in the permanent loss of the oceans? [/INDENT]
We already know that they are gone.
[INDENT]I personally think that by now, the Brown Tide is definitely dead. What we know of the stuff is it consumed water. Without there being water left on the surface of Athas, the Brown Tide would most likely be dead, or maybe in hibernation somewhere.[/INDENT]
Well if the theories above are correct, it's been in hibernation before, so why not again.
[INDENT]I'd think not from planes of water and air, but the plane of rain. Rain is the most hard-up of the paraelements, and could have seen an alliance with Rajaat as a good thing for it. Or if you don't like that theory, Rajaat had been studying the inner planes for a while, and could have gained mastery over parts of the plane of rain.[/INDENT]
Maybe it got tired of being called "that kinder gentler paraelement." :D
Brown Tide, still around or not? - If there's no water, I see no reason for there to be a brown tide. And, if the brown tide was able to go into long-term hibernation as opposed to being reduced to small pockets in the sea (that got out of control once the ecology of Athas became screwed up during the war), I'd think that it would also have hit the Last Sea and other "large" bodies of water still found on Athas. So, IMO, it's gone now, regardless of whether or not it contributed to the changing of the Silt Sea.
The Obsidian Plains and the boiling of the oceans - I'm pretty sure you can get fairly close to underwater volcanoes/magma without being boiled alive; that's a lot of water that is able to constantly pound against the magma, cooling it to rock. Water is a great conductor of heat, after all. Even with the sheer amount of magma generated during the event, I don't at all see it causing more than a localized boiling - where it touches the water and directly around that area it boils, but otherwise the magma hardens and the average temperature of the water in nearby areas goes up a wee bit. The amount of heat you'd need to raise the temperature of all the water on the planet even close to the point of boiling would be more than enough to also raise the temperature of the air to extreme levels - given its proximity to the Tyr Valley, there wouldn't have been anything left alive in the entire area.
On a related matter, however, the biggest effect that the quick heating of water has is the creation of currents - so although the water wouldn't have boiled off everywhere, it would have caused far-reaching, severe current changes (and eventually an overall warming of the oceans) that could very well have killed off most aquatic life over the following years, decades or centuries. Even then however you're not talking about scalding water going more than a few miles, if that - the temperature of deep water is extremely low, and there's a freakin' lot of water in you look at the total volume of it, and as these currents are moving around they're losing heat quickly the entire time.
Another problem with the "boiling off the oceans" theory - boiled water turns to steam, and steam expands. Anything remotely close to the edges of a boiling body of water would have been destroyed.
Just too much, too quickly to make sense. A change of global sea temperature and current patterns over the years following the event is much more likely, which in itself would be planet-altering, but it wouldn't have "destroyed" the seas per se.
Where'd the water go? - Unless it was truly "destroyed" (in some magical way, since you can't really "destroy" water any other way - the hydrogen and oxygen eventually re-binds and creates new water), it'd have had to go underground. If it went into the atmosphere it eventually would have rained back down on the planet, and global temperatures would be a lot hotter (as Xlorep pointed out) to boot. The fact that we've got a planet with 140-degree afternoons and no humidity is bad enough; if there was any real concentration of water in the atmosphere the heat index would be completely unbareable.
As it stands, the only places that get rain on a regular basis are the locations that are known to have high humidity and high concentrations of "ground-level" water - the Hinterlands, for instance. But in that case, at least, we're also talking an elevated location sitting up against an even higher mountain range, and mountain ranges tend to cause rain-condusive weather patterns.
- The sun's increase in size had affected Athas' plate tectonics, causing the cracks to expand considerably, and much of the water had ended up draining to fill in below the surface.
- Somehow much of the water ended up being shunted to one of the inner planes, most likely the plane of water.
The 'Obsidian Caticlysm', while impressive, does not explain the loss of water. It could have, as Dirk mentioned, caused drastic current shifts and changes, but not get rid of it all.
Even my theory of reawakening the Brown Tide isn't perfect, but if combined with the notion of the Obsidian Caticlysm affecting the currents, possibly the currents shifted around something on the sea bed, that brought the Brown Tide bacterium/algae out of its dormant state.
We know that Rajaat was tinkering with the pristine tower, right? And the pristine tower's main original purpose was to use the sun to get rid of the Brown Tide. What if Rajaat's twisting the pristine tower to serve his purposes damaged the components that the tower had to keep the brown tide in check? It stands to reason that his meddling around resulted in more or less 'short circuiting' the mutagenic qualities of the pristine tower causing creatures within range of the thing to randomly mutate in wierd and frequently lethal ways.
I mean, the stuff scared the crap out of the Rhulisti, and is what is most directly responsible for the Blue Age becoming the Green Age (including the mass reduction of water levels globally). The Brown Tide is something so powerful that the Rhulisti went to a great deal of effort to attempt to get rid of it before it destroyed the world.
Once awakened, and without any Rhulisti there to recognize it for what it was, it could have appeared like a mud-slick spreading across the oceans, rapidly reproducing and expanding, while doing what it did to tear apart the oceans. It is more or less a genetically-engineered monstrocity, that once it finished off the oceans, it ran out of 'food', and died out completely then. The Last Sea could easily be explained as simply having already been more or less separated from the main water sources before the Brown Tide could reach it.
As was suggested before, if people had been very busy dealing with the Cleansing Wars at the time, they could have not been paying much attention to it. They could have thought that the Brown Tide was only mud kicked up in the water. The Brown Tide could have destroyed the vast majority of the salt water sources across the globe. The fresh-water sources could have already had damage to them (from the afore-mentioned tectonic shifts), resulting in many of them pouring into new underground lakes.
If the Brown Tide was to have consumed the oceans, that would be one hell of a lot of that bacterium/algae (never really clear which it is, I'd guess possibly it has attributes of both, being something lifeshaped) in an ever-decreasing volume of water. Once the water got low enough, it would appear to be almost like a sludge. The heat of the sun would bake it, drying it out and killing the stuff. The dead 'husks' of the Brown Tide bacterium/algae would for all intents and purposes appear to be like dust... or Silt. Mix in volcanic ash, eroded earth, some defiler's ash, and other such things into the mix, and you have what is known as the modern Sea of Silt.
A couple things that your "summary" made me think of:
1) When Sadira and her sister are in the Pristine Tower, her sister begins to defile the pool. If I recall correctly, Denning describes a "brown discoloration" or something similar spreading throughout the pool right before she's killed. In an interview with him I think it was even asked whether or not this related to the Brown Tide, and his response (as I recall) was something like "that sounds like something I'd do, doesn't it?" So your theory as to the tower, the "twisting" of its power as caused by Rajaat, etc. all fits in with the idea of a ressurgence of the Brown Tide, I think. The more I sit here thinking about it, the more I like the idea, even.
2) Plants, like animals, are largely composed of water (I did a quick Google search and found a number stating that "woody" plants are about 50% water while herbaceous plants are 80-90% water). The Green Age is named that because that's what color it was - green with an abundance of plant life. It's reasonable to assume then that as part of the change from the Blue to Green Age, a good percentage of the drop in global water levels was due to the ocean-water being "converted" into all these trees, yes? Can't forget that, in order to have that many trees you also need a good amount of rainfall, so that would contribute as well. Now, as you (Xlorep) pointed out earlier, when plants are turned to ash the water in them is either "going somewhere" or else is destroyed in the process...and I have to agree with the latter, since if it wasn't somehow "destroyed" you'd end up with a more humid atmosphere, which in turn would raise global temperatures as well as increase precipitation, etc. (all the things we don't see on Athas). Now, if you go with this premise, then the demise of the Green Age - namely, the loss of all that plant life - would directly contribute to the loss of water as well. And, even if you *don't* consider that defiling destroys water, it still results in greater concentrations of water winding up underground (since you don't have the plants to help "bring it up" as it were). So either way, I'm thinking that this directly relates to the question of "where did all the water go?" and by relation the disappearance of the seas.
Xlorep, I think your "a little bit of all these ideas" concept is, overall, the best way of explaining this; trying to focus the creation of the Silt Sea on a single event, or even claiming that one event "dominated" the others in causing it, is too difficult to rationalize into a sensical hypothesis.
Well, there's just something about 'a bunch of little, seemingly unrelated events coalescing together to result in some major catastrophy' (little being a relative term here, we are talking about an expanse of global oceans and billions upon trillions of gallons of water here) which I personally like.
A couple things that your "summary" made me think of:
1) When Sadira and her sister are in the Pristine Tower, her sister begins to defile the pool. If I recall correctly, Denning describes a "brown discoloration" or something similar spreading throughout the pool right before she's killed. In an interview with him I think it was even asked whether or not this related to the Brown Tide, and his response (as I recall) was something like "that sounds like something I'd do, doesn't it?" So your theory as to the tower, the "twisting" of its power as caused by Rajaat, etc. all fits in with the idea of a ressurgence of the Brown Tide, I think. The more I sit here thinking about it, the more I like the idea, even.
Well, those details did have a hand in influencing my idea.
2) Plants, like animals, are largely composed of water (I did a quick Google search and found a number stating that "woody" plants are about 50% water while herbaceous plants are 80-90% water). The Green Age is named that because that's what color it was - green with an abundance of plant life. It's reasonable to assume then that as part of the change from the Blue to Green Age, a good percentage of the drop in global water levels was due to the ocean-water being "converted" into all these trees, yes? Can't forget that, in order to have that many trees you also need a good amount of rainfall, so that would contribute as well. Now, as you (Xlorep) pointed out earlier, when plants are turned to ash the water in them is either "going somewhere" or else is destroyed in the process...and I have to agree with the latter, since if it wasn't somehow "destroyed" you'd end up with a more humid atmosphere, which in turn would raise global temperatures as well as increase precipitation, etc. (all the things we don't see on Athas). Now, if you go with this premise, then the demise of the Green Age - namely, the loss of all that plant life - would directly contribute to the loss of water as well. And, even if you *don't* consider that defiling destroys water, it still results in greater concentrations of water winding up underground (since you don't have the plants to help "bring it up" as it were). So either way, I'm thinking that this directly relates to the question of "where did all the water go?" and by relation the disappearance of the seas.
Well.... when a world is more or less a 'water world', there already would be a lot of water in the air, higher humidity, and more precipitation than otherwise (think about where the biggest, strongest storms reside on Earth). The plant life of the green age could help account for some of the water, but I don't think it is that much of an impact. I mean, there was aquatic flora and fauna during the Blue Age -- arguably full ecosystems. The Brown Tide was marked as a major ecological disaster that radically changed the face of the world.
However, that said, the plants & vegitation would have had a lot of water in them. Once dead, and the land more or less left sterile, that would have huge impacts on the environment and ecology of the area. The Cleansing Wars had to have had a lot of rampant defiling involved (however, Borys' rampage also made a huge impact on the vegitation and life in the Tablelands region). Historically, there is evidence of potential damage that sterilizing a region and killing off the life there would do.
Alexander the Great (or was it one of the Romans) was noted for not only conquering a region, but also those regions that proved to be too difficult to handle, salting the land -- effectively sterilizing it and making it toxic to the plant life there. This extended the already growing desert regions, and those places that were salted still have difficulty being able to grow anything on them (the Sahara isn't completely a natural occurance). If defiling left a scar on a region like salting the land does (and I'd argue defiling would be worse), then the plants would be dead for centuries, without the plants, the humidity would be considerably less, and quickly the area would become an arid desert wasteland (like Athas is). Of course, the single greatest problem with this is once again, the question of 'where did the water go'?
We know that people live on the surface of Athas, without the benefit of great waterways. To me, that means there must be some accessable water underground. If people have been living at the locations of the city-states for two thousand years, that means there's some rather substantial resevoirs of water underground, especially without any form of precipitation to note (which would potentially replenish this water supply). So, reason would suggest that a good portion of the water went underground. But, this water is apparently drinkable (since I doubt they are desalinating the water), so it is somewhat fresh (a relative term, I'd doubt if we'd like Athasian water much). The oceans, being mostly saltwater, would not really be hidden away in these resevoirs... leaving the idea of the Brown Tide having finished off the saltwater systems.
I'm currently trying to come up with some pseudo-scientific way that we could break apart vast quantities of water molecules into oxygen and hydrogen and re-combine them with other elements present on Athas to effectively "get rid" of the water. So far we could explain away some of the oxygen as having bound to carbon and calcium from things killed both during the various Age-transitions as well as the Cleansing Wars, resulting in calcite (limestone) - there could be tons of this stuff compacted down at the bottom of the silt seas (although Valley of Dust and Fire says there's just bedrock down there
). Plus, we can throw iron oxide everywhere by combining the questions of "where the heck did all the metal go to?" plus "where's the water?" - as all this water is being broken apart, the increase in oxygen levels around the planet helps to speed up the rate at which metal items are oxidizing, thus getting rid of a bunch of the metal that was in existence during the Green Age as well as "using up" more of the water.Can't think of anything to do with the hydrogen, though.
In some other thread regarding water supplies I mentioned that, given that the tablelands are basically the bedrock of an ancient ocean, and coupled with the fact that we *do* have city-states that have survived in the same location for thousands of years, odds are there's a good amount of underground water to be had.
I knew I got the idea from somewhere
I'm currently trying to come up with some pseudo-scientific way that we could break apart vast quantities of water molecules into oxygen and hydrogen and re-combine them with other elements present on Athas to effectively "get rid" of the water. So far we could explain away some of the oxygen as having bound to carbon and calcium from things killed both during the various Age-transitions as well as the Cleansing Wars, resulting in calcite (limestone) - there could be tons of this stuff compacted down at the bottom of the silt seas (although Valley of Dust and Fire says there's just bedrock down there
I like the idea that the destruction of the water also impacted the loss of metal. Another of my pet theories about much of the metal is that the sorcerer-kings have a ton of metal stuff all stockpiled (like a typical dragon's hoard) and secreted away beneath their city-states, without anyone knowing about it. Some of that could have worn out because of increased oxygen levels, to be sure.
Also, bear in mind, O2 and H2 don't just rush to get bonded to become water molecules. Once the original chemical bonds were broken, they would reform in what would be the quickest connections. For hydrogen, that would be with other hydrogen. Oxygen could have mixed back with it as well, but considering how weightless hydrogen is, there may not have been much of a chance to.
Can't think of anything to do with the hydrogen, though.
Hydrogen is the single most common element in the universe. It is lighter than air, has virtually no gravitational force to it. Hydrogen, even on Earth, frequently escapes the Earth's gravitational pull, being released into open space (albeit some of it remains behind in the upper stratosphere). Where do you think the hydrogen released from the destruction of the water went to? It's gone -- as in could have escaped Athas' gravity. Especially with the extra heat the Athasian sun provides (making the hydrogen molecules be more aggitated and more capable of leaving Athas' gravity). Sure, some of it could have picked up and bonded with other molecules in the atmosphere as it progressed upwards and away from the surface, but I'd bet a good portion of it simply isn't to be found on Athas any longer.
From wikipedia (edited for size):
In normal thermal escape (sometimes known as Jeans escape), gases generally escape very slowly. ...The more massive a gas molecule is, the lower its average speed at a given temperature, meaning it is less likely to escape. This is why hydrogen escapes from a given atmosphere more easily than carbon dioxide. Also, if the planet has a higher mass, the escape velocity is faster and fewer particles will escape. ... ...hotter atmosphere, which generally leads to a faster range of velocities, and more chance of escape.
Current calculations put Athas at a size smaller than that of earth, it obviously has a much higher average atmospheric temperature than Earth, and of course hydrogen is the lightest of the elements.
So here goes:
- The Brown Tide, defiling, the great magma cataclysm, and sun changes results in vast quantities of water being broken down into hydrogen and oxygen molecules.
- Rising temperatures cause most of the hydrogen to escape.
- Much of the oxygen combines with iron weapons, armor and equipment used during the Cleansing Wars, turning into rust which, over the millenia, is dispersed throughout Athas, helping to create it's "red planet" appearance.
- Other oxygen combines with the calcium and carbon left over by the deaths of billions upon billions of living creatures killed by the Brown Tide, the Cleansing Wars, defiling magic and the continuing loss of surface water to create calcite, which comes to rest at the bottom of the silt seas and elsewhere on Athas (I recall their being all sorts of references to limestone being used in the city-states, covering vast tracts of land, etc. in the Wanderer's Chronicle).
- Other oxygen simply sits in the atmosphere, boosting the overall oxygen content of the air which, until some crazed wizard decides to make a spell to measure it, shall go unknown. However, an increase in oxygen levels does favor animal life over plant life, reducing the amount of plant life needed to convert carbon dioxide back into breathable atmosphere and thus keep the ecosystem going...something befitting of a planet that doesn't (IMO at least ) have an appropriate ratio of plants to animals.
- Hydrogen and oxygen that isn't used up in one of these other processes reforms into water in the atmosphere. Much of this simply stays put, giving Athas a low humidity overall but still "using up" some of this water.
- Of the water that turns to precipitation, it either creates mini ecosystems along the Forest Ridge and elsewhere where conditions make the combination of rainfall and plant life more feasible or else is absorbed into the parched ground. Given the vast quantities of rock present as the "ground" on Athas, any water able to collect as a liquid is either going to be re-absorbed into the atmosphere during the heat of the day or else sink down into undeground aquifers.
Xlorep, have at it. ;)
Solar wind escape mechanisms
There are a wide range of ways that the solar wind can lead to the loss of atmospheric particles. Generally, they involve charging the particle that will be lost, which leads to 'pick-up' by the charged solar wind. These mechanisms usually follow the same pattern as the Jeans escape described above, in that they are more likely to erode lighter atoms from lighter planets. However, in this case a magnetosphere helps protect against loss. It deflects the solar wind, and prevents its ions and magnetic field from carrying away atoms.
On planets without a magnetosphere, some combination of solar wind mechanisms very often dominate atmospheric escape. Both Venus and Mars are currently losing their water this way. First, the water is dissociated into hydrogen and oxygen by ultraviolet light from the Sun, and then the light hydrogen is pulled away in the solar wind. In fact, hydrogen from Venus has been detected at Earth.
I marked the part that is of key interest here. If the changes that the Athasian sun had gone through had changed the spectrum of light from it to have a higher amount of ultraviolet in it, that could have also helped with dissociating much of the water in the atmosphere. If memory serves, that's also a key way to form ozone as well. If the obsidian caticlysm did throw a bunch of water into the air (boiling it), then that water could have been dissociated by the increased ultraviolet radiation being given off by the Sun, which the hydrogen gets 'whisked away' while the oxygen forms a thicker upper stratosphere ozone layer (which begins to cut off the amount of ultraviolet that is let through the atmosphere, once again, if memory serves).
The sun's increased radiation could have had detrimental effects to people, which could have been seen as some sort of wasting disease or curse, which then the Champions could have used as a rallying cry to speak out against non-human races -- "look, the Elves have cursed us, made our people sick and infirm! We need to fight back before they wipe us all out!" Easier to place the blame, especially when the real cause probably went completely unknown. Even with a thicker ozone layer (and there are a couple huge lava rifts on the surface seriously attacking that layer) there is still other problems associated with the change in solar radiation. I've regularly thought that if an Athasian *was* to be put on another world, the sun of that world would most likely be too 'bright' (I like the notion that mid-day brightness on Athas is closer to twilight brightness on other worlds; it is a 'dark sun' after all) to them, but also much colder. But the Athasian would have some good resistance to heat.
But yea, I like that summary you made.
See, kids? Science is both fun *and* rewarding.
Woot.
See, kids? Science is both fun *and* rewarding.
In the end, it really doesn't matter to a campaign, but intellectual exercises can be quite fun.
Maybe it ran off with the metal and there's a big pool of metal hydride sitting around somewhere ;) Talk about "boom"!