[meteorite-list] AD(?) - Sikhote-Alin in tree
From: John.L.Cabassi <John_at_meteoritecentral.com>
Date: Wed, 12 Jan 2011 18:50:08 -0800 Message-ID: <A5CA9790D8DB439BBAB21371660AEC8A_at_anitak9bz49jy2> G'Day Anne, Dr. Vann, Dr. Ted and List I have to double that wow. I too have learned a lot today. I'm truly impressed. I'll be looking at trees now with a different perspective. Cheers John IMCA # 2125 -----Original Message----- From: meteorite-list-bounces at meteoritecentral.com [mailto:meteorite-list-bounces at meteoritecentral.com] On Behalf Of Impactika at aol.com Sent: Wednesday, January 12, 2011 5:04 PM To: drvann at sas.upenn.edu; meteorite-list at meteoritecentral.com Subject: Re: [meteorite-list] AD(?) - Sikhote-Alin in tree WOW! Thank you Dr. Vann, Dr. Ted, Dolores, everybody, for all the great posts! I have learned a lot about trees today! ;-) Dr Vann, if I was a little closer to Philadelphia, I would be driving right over to show it to you. Your analysis and interpretation is amazing, and very helpful. If more pictures could help in any way just say so, I would be delighted to send you some close-ups. And just in case, I posted this one to my site: _http://www.impactika.com/images/satree2.jpg_ (http://www.impactika.com/images/satree2.jpg) Please do let me know what you see there. Thank you very much. And for everybody else, and since some did ask, here is a picture of the two Sikhote-Alins from the Vernadsky Institute: _http://www.impactika.com/images/satree2.jpg_ (http://www.impactika.com/images/satree2.jpg) Enjoy. And again, Thanks everybody! Anne M. Black _http://www.impactika.com/_ (http://www.impactika.com/) _IMPACTIKA at aol.com_ (mailto:IMPACTIKA at aol.com) President, I.M.C.A. Inc. _http://www.imca.cc/_ (http://www.imca.cc/) In a message dated 1/12/2011 2:09:16 PM Mountain Standard Time, drvann at sas.upenn.edu writes: I would like to add that the picture, as I interpret it, is a tree *stump*. It is upside-down in Anne's picture. The 'branches' are departing the trunk in the pattern typical of roots. The age of the tree would be determined based on the rings in the piece laying on the table. It appears to me that the tree grew around the SA piece as it lay buried, consequently an age less than or near to the SA would be expected. There seems to be very little to no disruption (shattering) of the wood that I can see -only bending as one might see in a root growing around a rock. Thus, this may have been a fragment that hit soil, followed by enclosure in the growing tree. If you invert the photo (it will look more like a tree trunk), the placement of the fragment is below the main trunk. A moving piece would have come in on a very low angle to penetrate the tree in the *apparent* manner. Additionally, I would expect the oxidation patterns for meteorites that imbedded in wood to be different from that in soil (not possible to evaluate in a photo). At least, there should be iron staining or increased iron in the wood after impact due to natural organic acids in the tree sap as it repaired the wound. Conversely, a piece in the soil would be enclosed by roots similar to way they would enclose rock, and the root would have bark covering the wood at the interface with the fragment at all times, so there would be no iron staining. Interpretation is complicated by the fact that a second tree (probably a second trunk of the main tree) has grown roots that are interlaced with those of the larger trunk. If you invert the photo, the pear-shaped form on the right (with a circle in the center) is the remnants of the second trunk, which died and fell away from the tree years ago. The two yellowish ovals are two roots that were cut to fell the tree or after felling to better show the fragment. The pinkish area around the fragment is a larger root (that was plunging into the soil) that was split when the tree was uprooted. This split revealed the fragment. The split root shows a rotted, hollow area toward the right, which when combined with the cluster of three smaller roots (under the yellow ovals), provided a weak point for the split to begin. There is a crescent-shaped area of bark departing the fragment; this is the fusion/grafting line between the two large roots that are in the lower left of the (inverted) photo. This provides another point of weakness. I would love to see this in life, for a better evaluation, but am afraid that I cannot make the Tucson show. Someday perhaps. David R. Vann, Ph.D. Forest Biogeochemistry and Physiology Department of Earth and Environmental Science THE UNIVERSITY of PENNSYLVANIA 240 S. 33rd St. Philadelphia, PA 19104-6316 drvann at sas.upenn.edu office: 215-898-4906 FAX: 215-898-0964 | -----Original Message----- | From: meteorite-list-bounces at meteoritecentral.com | [mailto:meteorite-list-bounces at meteoritecentral.com] On | Behalf Of Dolores Hill | Sent: Wednesday, January 12, 2011 1:54 PM | To: John Birdsell | Cc: Impactika at aol.com; meteorite-list at meteoritecentral.com | Subject: Re: [meteorite-list] AD(?) - Sikhote-Alin in tree | | | Dear meteorite-list, | | I cannot resist commenting on this issue. I have studied | dendrochronology and I am very familiar with the UA Tree-Ring Lab | (LTRR). It is much more complicated than one might realize. In | addition to "number of tree-rings/years," the growth _/pattern/_ is | extremely important in cross-dating a tree sample according to a | particular regional "chronology." Depending on the species and/or | environmental conditions, there may even be "missing rings or double | rings." The number of rings also depends on when the tree | first started | growing and when it died (naturally or was cut down) or was | sampled by | increment core. | | I have seen fascinating photos of supposed Sikhote-Alin | meteorites stuck | in trees and invited the owners to allow LTRR experts to | examine them. | So far the owners seem to get cold feet. LTRR has scientists and | visiting researchers who have first-hand experience with | Russian trees | and forests. They are happy to provide assistance: | http://ltrr.arizona.edu/ If authentic, the samples might aid | studies of biological effects of meteorite impacts. It would | be best if | the original location of the tree is known; another case for careful | documentation. | | Regards, | Dolores Hill | Lunar & Planetary Laboratory | University of Arizona | | | John Birdsell wrote: | > Hi Ted....good point. If a tree branch was collected many, | many years | > ago, it | > could have fewer growth rings, and might also be expected | to show some signs of | > its age. | > | > | > -J | > | > I have seen three specimens that exceed 80 years and | several that are | > too | > young, so be careful. A Russian dealer friend of mine says | that all of the | > genuine specimens were gathered years ago, but some may | have been kept for | > future sale as we know the Arab dealers do with meteorites. | > | > Be careful out there. | > | > Ted Bunch | > ______________________________________________ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list at meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list Received on Wed 12 Jan 2011 09:50:08 PM PST |
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