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Author Topic:   Solving the Mystery of the Biblical Flood
joz
Inactive Member


Message 44 of 460 (2724)
01-24-2002 4:04 PM
Reply to: Message 43 by wmscott
01-24-2002 3:59 PM


quote:
Originally posted by wmscott:
"So, was that your college geology textbook?" I have read many geology textbooks, but I have never been to college as a student.

Alarm bells are ringing.........

This message is a reply to:
 Message 43 by wmscott, posted 01-24-2002 3:59 PM wmscott has not replied

joz
Inactive Member


Message 203 of 460 (6744)
03-13-2002 11:17 AM
Reply to: Message 199 by wmscott
03-12-2002 4:35 PM


quote:
Originally posted by wmscott:
...impact melted water flowing off the ice sheet and into the sea...

What?
Look up papers by Dr M.J.Burchell the next time you have a chance, he`s done work on impact cratering in ice...
On impact some ice is vaporized (forming the crater) the rest predominantly remains solid (hence there is something for there to be a crater in)...
If there was any water around it certainly wouldn`t be running off into the sea it would be in the bottom of the crater....
Oh and for reference it would be highly unlikely that an impact crater would form in rock shielded by kilometers thick ice, the crater would be in the ice itself....

This message is a reply to:
 Message 199 by wmscott, posted 03-12-2002 4:35 PM wmscott has not replied

joz
Inactive Member


Message 206 of 460 (6758)
03-13-2002 6:53 PM
Reply to: Message 205 by wmscott
03-13-2002 4:59 PM


You seem to have missed the point, you used the phrase "...impact melted water flowing off the ice sheet and into the sea..."
There wouldn`t be any because impact cratering on ice works by vapourizing the ice that was where the crater forms and the rest of the ice remaining solid so that there is a crater....
IOW no impact melted water.....

This message is a reply to:
 Message 205 by wmscott, posted 03-13-2002 4:59 PM wmscott has not replied

joz
Inactive Member


Message 218 of 460 (7028)
03-16-2002 3:28 PM
Reply to: Message 209 by wmscott
03-14-2002 4:17 PM


quote:
Originally posted by wmscott:
1)...the abstract seemed to imply that the paper was on ice impact events in a vacuum designed to investigate impacts between material in the solar system such as comets. Which is why a number of the experiments have been done with a mixture of water ice and dry ice CO2..
2)In an impact event in space, yes there would be no melted ice, at least not for very long. In an atmosphere, heating of the air and surface, results in temperatures very possibly above the freezing point.
3)In the case of an over lapping pattern of Carolina bay type impacts, wide spread heating of the atmosphere and ice surface is to be expected.
4)If nothing else the ejected ice fragments would gain enough heat to melt at least partly from the kinetic energy imparted to them. The impacts would have delivered a lot of kinetic energy to the ice sheet surface, some of the energy would have ended up in the form of heat.
5)Think of it this way, where did all of the comet impact energy go? The only other place is in the kinetic energy given to the ejected ice, but since the impactors had to pass through the atmosphere we know some of the energy was turned into heat.
6)The ejected fragments had air friction and a secondary impact if they didn't vaporize in the air. With all this energy being tossed around, there probably would have been secondary melting.
7)Plus with much of the ejected ice vaporizing or melting, there was plenty of water to run off into the sea.
8)Then there was also the water the impact shocks released from sub glacial lakes, and ice dammed lakes, and the possible shock induced surging.

First you seem to misunderstand the mechanism of impact crater formation...
If a body hits another body travelling faster that the maximum speed of propogation of a shock wave through the impacted medium (Hypervelocity) the kinetic energy arrives faster than it can dissipate. This leads to a sharp rise in temperature at the impact site. This increase in temperature vaporizes the impacting body and material from the impacted body forming a crater...
Note the word vaporizes NOT makes liquid...
So now onto your post...
1)Well yes it was in a vacuum, have you ever tried firing a .5mm diameter streel ball bearing at 6Kms-1 through NEA? How far do you think it would get? How accurate would it be?
Also the experiments were conducted at room temperature so if the ice was going to reach a liquid state due to the impact it would do so in the experiment...
2)yes there wouldn`t be any melted ice (I assume you mean liquid water) in an impact in space it would be solid remainder and vaporized ejected material... NO water...
Pretty similar to an impact into ice on earth...
3)Atmosphere yes (though negligable), ice surface no...
The heat is dissipated by vaporizing the impacted material i.e it all goes into the (rather large and cold) atmosphere...
4)"ejected ICE fragments"????
There is no such animal bud the ejected material is vaporized, ergo is vapor i.e is not an "ice fragment"...
Practically all the kinetic energy is released as heat and practically all of it goes straight up into the atmosphere along with the water vapour.....
Not a lot remains in the ice sheet...
5)I know where it goes its you that seems to be having problems, it goes into the (rather large and cold) atmosphere with the water vapour, its dissipated through the atmosphere and it doesnt raise the atmospheric temperature by very much (by virtue of the atmosphere being very big and cold)....
6)Once again no such animal as "ejected fragments" and they certainly didn`t "vaporize in the air" because they vaporized before they left the surface....
As for secondary melting why the atmospheric temperature would barely change around the glacier...
7)a)Ejected = thrown up into the atmosphere, not going to run off over the ice sheets as you put it...
b)Ejected material is vapour not liquid water....
8)Which isn`t what you said with impact melted water running off over the ice sheets is it?
Also the shock waves only carry a tiny portion of the energy of the impact...
[This message has been edited by joz, 03-16-2002]

This message is a reply to:
 Message 209 by wmscott, posted 03-14-2002 4:17 PM wmscott has not replied

joz
Inactive Member


Message 222 of 460 (7296)
03-19-2002 10:41 AM
Reply to: Message 220 by wmscott
03-18-2002 4:30 PM


quote:
Originally posted by wmscott:
1)On the impacts you stated "As for secondary melting why the atmospheric temperature would barely change around the glacier..."
....A searing fireball ignited everything within miles and then the fire was almost immediately extinguished by the blast wave created by the explosion....
....A comet impact on earth is accompanied by a large release of heat hot enough to start forest fires at considerable distances from the impact area.....
2)...Seismographs sensed slight tremors, and barometric data recorded the passage of a pressure wave from the blast that rounded the planet several times."...
3)...Another author even speculated. " what actually happened eight thousand to ten thousand years ago to end the hunter-gatherer chapter in human history?...
4)...central Asian land and Amerind traditions describe the emergence of dry land from beneath a global ocean (a peculiar concept to arise among Plains Indians if they "invented" the story!). What did happen then?
(added by edit)
5)So even if all the water went into the air as vapor, much of it still would have ended up in the sea. But, as I stated, it is not possible for the atmosphere to hold so much water, so much of it had to fall out at once, which due to the abundance of heat released, much of it would have been in the form of rain. The explosive blasts of each impact would have blown surface materials out from each crater and the heat blasts would have melted or vaporized much of such as well

1)First up by secondary melting I thought you meant due to the increase in temperature of the total atmosphere after the initial impact, shock and blast...
Second think for a moment WMS if its hot enough that trees start to spontaneously combust will ice a)melt and remain as liquid or b)vaporize and disperse into the atmosphere as steam?
Now personally I think its b) what about you?
2)Just thought I`d point out slight tremmors hardly the sort of thing you expect to smash a couple of cubic kilometers of ice apart....
3)Possibly, and this is just a theory mind you, some bright young thing thought hey sod this running after the animals to kill them for a lark, lets put them in a pen so we know where they are....
And while we`re at it we could grow the plants we like to eat...
And thus agriculture was born...
4)It would be kind of freaky if they had always lived in the plains but didn`t their ancestors cross the (apologies for spelling here) baring straights from asia?
5)"...impact melted water flowing off the ice sheet and into the sea..." is the exact phrase that I objected to...
I know that a lot of water is thrown up into the atmosphere but its hardly relevant to the phrase I objected to....
Just for reference I think that you are vastly overestimating the ammount of water released to the atmosphere...
Also once again please note that an impact event is not an explosion as such and material ejected would predominantly (close to 100% there of) be vaporized...
[This message has been edited by joz, 03-19-2002]

This message is a reply to:
 Message 220 by wmscott, posted 03-18-2002 4:30 PM wmscott has not replied

joz
Inactive Member


Message 235 of 460 (7439)
03-20-2002 9:03 PM
Reply to: Message 224 by wmscott
03-19-2002 4:21 PM


quote:
Originally posted by wmscott:
1)There would be both steam and water from the effects of the impact heat depending on the distance from the impact.
2)Frankly, it doesn't matter too much whether the water was liquid or vapor since the vapor would have rained out anyway and the effect would be pretty much the same in the end.
3)I was only looking to the impact shocks as a source of hydraulic pressure shock waves in the sub glacial lakes and water, resulting in simultaneous releases and the possible cause of some surging triggered by the termors.
4)Whether or not the shocks shattered the ice into pieces doesn't matter much, how much ended up in the sea to raise the level is the important part.
5)The change in things at the end of the ice age was to pronounced to be the result of a mere change in life style. Read about the Pleistocene extinction and the disappearance of Neanderthal man.
6)Yes they did get to the Americas by crossing water, but when did they get there? And why do the people living in Asia who didn't have to cross water at all, still have the same story? This suggests a common source before migration occurred.

1)I`m not arguing that the water is lost merely that if its vapour it won`t be "...impact melted water flowing off the ice sheet and into the sea..." as you put it... Also there wouldn`t be a lot of liquid water around plenty of vapour but not a large amount of liquid water...
2)Once again I`m not arguing that the vapour stays in the atmosphere, this whole conversation is about your use of the phrase "...impact melted water flowing off the ice sheet and into the sea..." which implied a lack of understanding of the mechanisms involved...
But I think you`ll find that the ammount of water released by an impact or series of impacts insufficient to cause a global flood....
3)Keep looking your own source for the Siberian impact states "Seismographs sensed slight tremors" note "slight tremmors"...
4)The shock wave does have to shatter solid ice in order for any sub glacial lake release pal, at the edges of the ice sheet, unless you think that hydraulic pressure could force the water through solid ice leaving said ice intact...
5)Lets see from this site...
The Pleistocene
quote:
It was during the Pleistocene that the most recent episodes of global cooling, or ice ages, took place. Much of the world's temperate zones were alternately covered by glaciers during cool periods and uncovered during the warmer interglacial periods when the glaciers retreated. Did this cause the Pleistocene extinctions? It doesn't seem likely; the large mammals of the Pleistocene weathered several climate shifts.
The Pleistocene also saw the evolution and expansion of our own species, Homo sapiens, and by the close of the Pleistocene, humans had spread through most of the world. According to a controversial theory, first proposed in the 1960s, human hunting around the close of the Pleistocene caused or contributed to the extinction of many of the Pleistocene large mammals. It is true that the extinction of large animals on different continents appears to correlate with the arrival of humans, but questions remain as to whether early human hunters were sufficiently numerous and technologically advanced to wipe out whole species. It has also been hypothesized that some disease wiped out species after species in the Pleistocene. The issue remains unsolved; perhaps the real cause of the Pleistocene extinction was a combination of these factors.

So we hunted things out of exsistence (or they dropped dead of disease) so we started rearing them as livestock to make our lives easier...
WTF are you trying to imply? That forming permanent or semi permanent settlements and adopting agriculture isn`t going to cause a huge change in lifestyle from hunter gathering....
Why do you think this would not cause a huge change in lifestyle...
6)So lets see they came from asia where there are also flood myths, they live well away from the sea. Thus the myths were probably brought with them from asia which makes it rather disingenuous to write "...Amerind traditions describe the emergence of dry land from beneath a global ocean (a peculiar concept to arise among Plains Indians if they "invented" the story!)" i.e "there must have been a flood because these people who live nowhere near the sea now have this myth..." or to claim that interior asian peoples always lived in the interior...

This message is a reply to:
 Message 224 by wmscott, posted 03-19-2002 4:21 PM wmscott has not replied

joz
Inactive Member


Message 250 of 460 (7987)
03-29-2002 12:46 PM
Reply to: Message 242 by wmscott
03-28-2002 4:35 PM


quote:
Originally posted by wmscott:
1)On 'water running off the ice sheet' we are wasting our time splitting hairs. As I posted earlier on the Tunisia impact, there would have been plenty of heat involved which would have resulted in large amounts of ice melting. I am not even looking to impact melted water as the major source of flood waters, so this is really a pointless argument.
2)"your own source for the Siberian impact states "Seismographs sensed slight tremors" note "slight tremmors".." The Siberian 'impactor' exploded at 10,000 ft above the ground and still caused a tremor. Direct impacts exploding on impact would create much larger termors. Think about it, what would you expect from a hyper velocity impact, a little tap or a big wham? Think about getting rear ended at a stop light, the faster the car that hits you is going, the larger the jolt is going to be.
3)"The shock wave does have to shatter solid ice in order for any sub glacial lake release" Not directly, the pressure wave created in the sub glacial water could have been the hammer that broke the ice dams. Also, large ice sheets frequently, if not always, have a vast plumbing system of moving water draining over, through and under the ice sheet.
4)On the information you posted on the change in live style recorded at the end of the ice age, none of it really answered why it happened. The over hunting, climate change and super germ theories are not very plausible which is why there are three theories in stead of just one.
5)The weight spread out over all the ocean floors would add up to quite a force.

1)Fact is bud there wouldn`t be any "impact melted water flowing off the ice sheets" as you put it for the simple reason that the heat released by the impact would vaporize rather than melt the impacted ice....
IOW apres impact there would be solid ice (with a crater in it) and vast quantities of water vapour (the material that was in the crater) not torrents of liquid water as you seem to expect... yes there is huge ammounts of heat but that is precisely why the material would be vaporized rather than left as a liquid....
And yes it is pointless untill you read up on the physics of hypervelocity impacts....
2)See this is what I`m talking about right here, your analogy with car crashes is inacurate in that in car crashes the energy does not arrive faster than the maximum speed of propogation of the shock wave in the impacted body...
See the problem yet? The reason that so much heat is generated at all is that the energy of the impact cannot be dissipated by a shock wave...
You do not understand the mechanisms of hypervelocity impacts go and read up on them then we can discuss this...
3)Cute if you had read past the first sentance you would have seen that I made exactly the same point about the shock wave breaking the "ice dams" as you put it...
Oh incidently did you know that solids transmit shock waves better than liquids? What does this do to the idea that the shock wave was chanelled along the liquid chanel untill it hit an "ice dam"?
4)Regardless as to the theories as to why agriculture came about your original comment was along the lines of the move to agriculture from hunter gathering cannot solely explain the changes in human society, I would like to see some sort of justification of that statement....
5)Lets see now weight is mass times gravitational field potential which gives units of [Kgms-2] i.e units of force
Spread it out over an area and you get units [Kgm-1s-2] i.e pressure....
Yet you seem to think that its force....
When reading up on hypervelocity impacts read an introductory level physics text while your at it.....
[This message has been edited by joz, 03-29-2002]

This message is a reply to:
 Message 242 by wmscott, posted 03-28-2002 4:35 PM wmscott has not replied

joz
Inactive Member


Message 256 of 460 (8481)
04-12-2002 4:23 PM
Reply to: Message 253 by wmscott
04-11-2002 6:43 PM


quote:
Originally posted by wmscott:
1)There would be much vaporization of ice, but we are not dealing with a binary situation. Ice in the center of an impact would be vaporized, ice outside the crater would still be ice, and in between would be a zone where the heat would not be enough to vaporize, but enough to melt. Additionally in a dense impact pattern of multiple impacts as we have been talking about, there would be too much water vapor for the atmosphere to hold, due to the heat imparted to the vapor or steam, and the atmosphere, the excessive vaporized ice would rain out in a very heavy rain. Also in reading a journal article on this, they mentioned extensive fracturing of the ice with passage of the shock wave. Thus a Carolina bay type pattern of impacts, could have turned an ice sheet into a huge unstable pile of broken ice. Since a ice sheet grows as large as it can support itself, such a fracturing could result in a massive surging all by itself.
2)Actually it makes things easier, since the ice is extensively fractured by the shock wave itself and this can cause the collapse of an ice sheet without requiring the presence of large amounts of sub glacial melt water.
3)Consider the disappearance of Neanderthal man, and the change in populations that occurred at the end of the ice age. The study of human genes shows that the end of the ice age was a time of major change, for example, although there are a number of skeletons of human 'hybrids' no one a live today has Neanderthal genes. We also have the Pleistocene extinctions, the sudden climate changes and the sudden disappearance of ice age societies, whole tribes of people or in one case a whole race, up and disappeared. That is why I feel a gradual change from hunting to farming, fails to account for the many profound changes that occurred at the end of the ice age.
4)We are not in a introductory physics class. This may come as a shock to you, but words are not always used as they were in your physics class. In general usage, words are used much more loosely and frequently with more than one meaning. So chill out, unless I start using the wrongs terms in equations then you can point it out to me. On reading up on hypervelocity impacts, The university sent a lot of recent journals out to for binding, so I was only able to read one. Feel free to e-mail me any articles you think I should read. Otherwise I will just have to wait until they come back from the bindery.

1)I didn`t claim that it was a "binary" situation I said that there wouldn`t be enough impact melted water around to surge off the ice sheets...
Think about it the range in which water is liquid is (by definition) 100 degrees C (or K) as the heat dissipates only the region that is heated to this temperature range will end up as liquid... In comparison to the size of the crater this region is vanishingly small...
And I think you are underestimating the ability of the atmosphere to accomodate the vaporized material...
Why don`t you do some maths and show me that it couldn`t?
Which journal article?
So lets see "Thus a Carolina bay type pattern of impacts, could have turned an ice sheet into a huge unstable pile of broken ice. Since a ice sheet grows as large as it can support itself, such a fracturing could result in a massive surging all by itself."
So many coulds so little evidence.....
2)Of course it also means that the shock wave gets more diffuse and thus causes LESS damage at the edges of the ice sheet or at those "ice dams" of yours...
3)Change in enviroment leads to change in species, survival of fittest etc.....
We adapted better than them....
Also I thought that Neanderthals went extinct 35,000 years ago not 10,000...
Also the statement "no one a live today has Neanderthal genes" may not be as true as you think it is:
http://www.pro-am.com/origins/research/neand2.htm
4)I`ll give you a hint when talking about the force experienced due to gravity by a mass of water distributed over a given area force and pressure are NOT semanticaly equal...
If we were talking about forcing someone to do something pressuring would be an equivalent term, however in the context of the weight of a body of water and the distribution of said weight over a given area your semantic wriggling is invalid....
The longer we discuss this the less scientificaly capable you show yourself to be, to whit your misrepresentation of mitochondrial Eve....
[This message has been edited by joz, 04-12-2002]

This message is a reply to:
 Message 253 by wmscott, posted 04-11-2002 6:43 PM wmscott has replied

Replies to this message:
 Message 259 by wmscott, posted 04-18-2002 5:55 PM joz has not replied

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