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Post by Original Admin on Nov 9, 2007 5:57:36 GMT -5
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Post by Bikerrandy on Nov 9, 2007 6:02:09 GMT -5
Cool, we can make petified wood! ;D Interesting info
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adrian65
Cave Dweller
Arch to golden memories and to great friends.
Member since February 2007
Posts: 10,777
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Post by adrian65 on Nov 9, 2007 6:54:26 GMT -5
Thank you for posting it, Mark!
I wanted to share with you this document, that proofs the existence of rapid petrification. I often found on rivers banks pieces of wood that were very similar to the pet wood chunks that I've found there. Those pieces tricked me more than once, filling me first with hope and then with disapointment. Given this similarity, I suspected that the petrification takes place right in the river bank, if those pieces are covered with anaerob (tight) silt. But I had no idea this proces can occur so quickly.
Thanks,
Adrian
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chassroc
Cave Dweller
Rocks are abundant when you have rocktumblinghobby pals
Member since January 2005
Posts: 3,586
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Post by chassroc on Nov 9, 2007 9:00:18 GMT -5
I too did not realize how quickly it can occur. Our children and grandchildren will tumble lab created pet wood! csroc
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Post by Lady B on Nov 9, 2007 9:24:22 GMT -5
Thanks for sharing such interesting information!
Lady B
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Post by deb193redux on Nov 9, 2007 11:57:04 GMT -5
I understood some recently reported rapid-petrification was not a true silicification, but a kind of silica-ceramic. I now see a Japanese report more akin to true silicification. Rapid wood silicification in hot spring water: an explanation of silicification of wood during the Earth's history
Hisatada Akahane, Available online 25 July 2004.
Abstract A hot spring water lake in Tateyama Hot Spring has a high content of silica and readily precipitates silica spheres and deposits of opal. Abundant fragments of naturally fallen wood impregnated with silica were found in the overflow stream of the lake. These silicifications resulted from the precipitation of silica spheres onto split surfaces or cell walls of the fallen wood. The textures of wood tissues are the same as those found on naturally silicified wood formed in the vicinity of volcanic regions in the geological record. These results explain the formation mechanism of certain naturally silicified wood fragments that seem to be formed under the same conditions as those found in the hot spring water.
To confirm the silicification process, fresh wood pieces of alder wood (Alnus pendula Matsumura) were placed in the hot spring water stream. Experimental wood fragments were silicified to nearly 40% by weight over a period of 7 years by the deposition of amorphous silica spheres in cell lumina of wood tissue.
This study reveals that silicified wood can form under suitable conditions in time periods as short as tens to hundreds of years, and contributes to the understanding of the mechanisms forming
This strikes me as analogous to the fact that we can lab-grow diamonds in short periods of time, while natural diamonds, under ordinary conditions, take a very long time to form. It seems accurate to say that with hot enough water, the right pH, and ash with >98% silica content, that some sort of silica replacement can happen in dozens to hundreds of years. I love reading about this kind of stuff because I always want to know more about the geology and chemistry of the rocks I like. I hope the literature soon provides information on more massive pieces of wood, on the degree to which silicification of the outer edges slows completion of the center, and of the conditions that result in casts instead of replacement. One warning. Many creationist websites are trying to use studies like this to PROVE that ALL petrified wood is less than a few thousand years old - which is a totally unfounded leap of illogic. Just like most diamonds, most pet wood is very old. The sedimentology, fossil records, radiation levels, magnetic imprints ... etc all bear this out.
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fossilbrain
spending too much on rocks
Cookie Monster agate
Member since October 2007
Posts: 360
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Post by fossilbrain on Nov 9, 2007 14:05:12 GMT -5
I've noticed stony branches coming out of the Peace River in FL that I'd swear were made mostly of the same stuff as in the very silt I'm pulling them out of, which I thought was odd if they were actually petrified. Maybey this permineralization makes more sense. These are far too brittle, usually, to do anything but tumble, whereas other "pet wood" that came to me from Alaska you could do anything with, lapidary wise.
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