RE: [meteorite-list] Question on oriented SA shrapnel
Hi Göran, Yep, I've also got a few sikhote shrapnels with definite flow lines, so must have been due to detonation in the air, since I can't see how flow lines can form whist imbedding in a tree etc... Best Mark -Original Message- From: Jeff Kuyken [mailto:[EMAIL PROTECTED] Sent: Wednesday, August 10, 2005 2:20 AM To: Göran Axelsson; meteorite-list@meteoritecentral.com Subject: Re: [meteorite-list] Question on oriented SA shrapnel G'day Göran, My understanding (and I could be wrong here?) was that most Sikhote-Alin shrapnel was formed when the piece/s detonated in the air during its fall. Mike's piece is probably a good example of showing how the forces/pressure on that piece grew to such a point, the structure of the meteorite (coarsest octahedrite) was no longer able to support it. Cheers, Jeff - Original Message - From: Göran Axelsson To: meteorite-list@meteoritecentral.com Sent: Wednesday, August 10, 2005 9:42 AM Subject: Re: [meteorite-list] Question on oriented SA shrapnel I was looking through some of Michael Farmers auctions on Ebay and one piece made me puzzled. It was a 7 kg oriented Sikhote-Alin that had flowlines. I thought that all the shrapnel pieces were created when larger meteorites impacted and tore the metal apart. But flowlines should mean that this shrapnel were created in flight. My question is if there are shrapnel pieces created in flight? I have a neat oriented Sikhote-Alin in my collection, complete with flowlines, thumbprinting and even fractured surfaces and teared metal. It isn't a shrapnel and there still are some crust on the leading edge with finer flowlines in the crust. If a shrapnel piece would have crust with flowlines then I would be convinced that it was created in flight but isn't it possible that there could be similar structures without crust created when it hits the ground? I'm just curious as this is the first shrapnel I've heard about with flowlines. Regards, Göran Michael Farmer wrote: I have loaded another 53 meteorites on ebay, most starting at... -- snipp -- 7 kilo ORIENTED Sikhote-Alin piece. $4000.00 specimen, up for one cent. http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItemrd=1item=6551087736 -- snip -- Mike Farmer __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Question on oriented SA shrapnel
Göran, Mark, Jeff, List here a nice vizualisation of the fragmentation processes of Sikhote. According to this model, the pieces of the 3th and 4th fragmentation can't have flow lines. http://www.geocities.com/diane_va/sikhote-alin/index_E.html (click on The fragmentation) Martinho. - Original Message - From: mark ford [EMAIL PROTECTED] To: meteorite-list@meteoritecentral.com Sent: Wednesday, August 10, 2005 11:38 AM Subject: RE: [meteorite-list] Question on oriented SA shrapnel Hi Göran, Yep, I've also got a few sikhote shrapnels with definite flow lines, so must have been due to detonation in the air, since I can't see how flow lines can form whist imbedding in a tree etc... Best Mark -Original Message- From: Jeff Kuyken [mailto:[EMAIL PROTECTED] Sent: Wednesday, August 10, 2005 2:20 AM To: Göran Axelsson; meteorite-list@meteoritecentral.com Subject: Re: [meteorite-list] Question on oriented SA shrapnel G'day Göran, My understanding (and I could be wrong here?) was that most Sikhote-Alin shrapnel was formed when the piece/s detonated in the air during its fall. Mike's piece is probably a good example of showing how the forces/pressure on that piece grew to such a point, the structure of the meteorite (coarsest octahedrite) was no longer able to support it. Cheers, Jeff - Original Message - From: Göran Axelsson To: meteorite-list@meteoritecentral.com Sent: Wednesday, August 10, 2005 9:42 AM Subject: Re: [meteorite-list] Question on oriented SA shrapnel I was looking through some of Michael Farmers auctions on Ebay and one piece made me puzzled. It was a 7 kg oriented Sikhote-Alin that had flowlines. I thought that all the shrapnel pieces were created when larger meteorites impacted and tore the metal apart. But flowlines should mean that this shrapnel were created in flight. My question is if there are shrapnel pieces created in flight? I have a neat oriented Sikhote-Alin in my collection, complete with flowlines, thumbprinting and even fractured surfaces and teared metal. It isn't a shrapnel and there still are some crust on the leading edge with finer flowlines in the crust. If a shrapnel piece would have crust with flowlines then I would be convinced that it was created in flight but isn't it possible that there could be similar structures without crust created when it hits the ground? I'm just curious as this is the first shrapnel I've heard about with flowlines. Regards, Göran Michael Farmer wrote: I have loaded another 53 meteorites on ebay, most starting at... -- snipp -- 7 kilo ORIENTED Sikhote-Alin piece. $4000.00 specimen, up for one cent. http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItemrd=1item=6551087736 -- snip -- Mike Farmer __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
RE: [meteorite-list] Question on oriented SA shrapnel
Martin, Thanks for the link, very interesting, (though somewhat simplified imho). There have been quite a few oriented (with flow lines) SA shrapnel pieces pulled out of trees etc, it will be interesting to see if anyone has any idea's as to the formation mechanism. If the 3rd and 4th detonation/fragmentations where too low, (for there to be enough flight time for flowlines to form) and the explosion on impact (the normal shrapnel forming process) was not consistent with flowline formation, then the question is, how are they formed? I guess the flowlines on my SA shrapnel could conceivably be shock induced lines formed by the explosive energy during impact? But some of the examples ive seen pictures of, look exactly like normal flow lines. Best, Mark Ford -O riginal Message- From: Martin Altmann [mailto:[EMAIL PROTECTED] Sent: Wednesday, August 10, 2005 11:08 AM To: mark ford; meteorite-list@meteoritecentral.com Subject: Re: [meteorite-list] Question on oriented SA shrapnel Göran, Mark, Jeff, List here a nice vizualisation of the fragmentation processes of Sikhote. According to this model, the pieces of the 3th and 4th fragmentation can't have flow lines. http://www.geocities.com/diane_va/sikhote-alin/index_E.html (click on The fragmentation) Martinho. - Original Message - From: mark ford [EMAIL PROTECTED] To: meteorite-list@meteoritecentral.com Sent: Wednesday, August 10, 2005 11:38 AM Subject: RE: [meteorite-list] Question on oriented SA shrapnel Hi Göran, Yep, I've also got a few sikhote shrapnels with definite flow lines, so must have been due to detonation in the air, since I can't see how flow lines can form whist imbedding in a tree etc... Best Mark -Original Message- From: Jeff Kuyken [mailto:[EMAIL PROTECTED] Sent: Wednesday, August 10, 2005 2:20 AM To: Göran Axelsson; meteorite-list@meteoritecentral.com Subject: Re: [meteorite-list] Question on oriented SA shrapnel G'day Göran, My understanding (and I could be wrong here?) was that most Sikhote-Alin shrapnel was formed when the piece/s detonated in the air during its fall. Mike's piece is probably a good example of showing how the forces/pressure on that piece grew to such a point, the structure of the meteorite (coarsest octahedrite) was no longer able to support it. Cheers, Jeff - Original Message - From: Göran Axelsson To: meteorite-list@meteoritecentral.com Sent: Wednesday, August 10, 2005 9:42 AM Subject: Re: [meteorite-list] Question on oriented SA shrapnel I was looking through some of Michael Farmers auctions on Ebay and one piece made me puzzled. It was a 7 kg oriented Sikhote-Alin that had flowlines. I thought that all the shrapnel pieces were created when larger meteorites impacted and tore the metal apart. But flowlines should mean that this shrapnel were created in flight. My question is if there are shrapnel pieces created in flight? I have a neat oriented Sikhote-Alin in my collection, complete with flowlines, thumbprinting and even fractured surfaces and teared metal. It isn't a shrapnel and there still are some crust on the leading edge with finer flowlines in the crust. If a shrapnel piece would have crust with flowlines then I would be convinced that it was created in flight but isn't it possible that there could be similar structures without crust created when it hits the ground? I'm just curious as this is the first shrapnel I've heard about with flowlines. Regards, Göran Michael Farmer wrote: I have loaded another 53 meteorites on ebay, most starting at... -- snipp -- 7 kilo ORIENTED Sikhote-Alin piece. $4000.00 specimen, up for one cent. http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItemrd=1item=6551087736 -- snip -- Mike Farmer __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Question on oriented SA shrapnel
I've been around this so long ,it never occured to to think this was the result of ground impact, but I understand how it would look that way. When one thinks about it, All or the SAwe find was shrapnel-form at the beginning of breakup. Fragments which separated earlier had longer opportunity to round off and regmaglypt. So far as I understand the physics, shearing stress which exceeds the cohesiveness of the meteoroid body can begin high up(15miles?) where the density of the atmosphere presents enough resistance and reaches maximum around 5 miles above sea level. I think the artwork suggests a massive main body disruption high up , which would have yielded a swarm. Seems there were perhaps a few subsequent bursts down the smoke stream. We might want to look at the SA Postage Stamp again. When you see shrapnel which is ripped and torn and remember this is iron we are talking about, this only gives a glimpse of what terrific energy absorbing potential the atmosphere has. Quiet Awe inspiring! Elton Göran Axelsson wrote: My question is if there are shrapnel pieces created in flight? __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Question on oriented SA shrapnel
I was looking through some of Michael Farmers auctions on Ebay and one piece made me puzzled. It was a 7 kg oriented Sikhote-Alin that had flowlines. I thought that all the shrapnel pieces were created when larger meteorites impacted and tore the metal apart. But flowlines should mean that this shrapnel were created in flight. My question is if there are shrapnel pieces created in flight? I have a neat oriented Sikhote-Alin in my collection, complete with flowlines, thumbprinting and even fractured surfaces and teared metal. It isn't a shrapnel and there still are some crust on the leading edge with finer flowlines in the crust. If a shrapnel piece would have crust with flowlines then I would be convinced that it was created in flight but isn't it possible that there could be similar structures without crust created when it hits the ground? I'm just curious as this is the first shrapnel I've heard about with flowlines. Regards, Göran Michael Farmer wrote: I have loaded another 53 meteorites on ebay, most starting at... -- snipp -- 7 kilo ORIENTED Sikhote-Alin piece. $4000.00 specimen, up for one cent. http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItemrd=1item=6551087736 -- snip -- Mike Farmer __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Question on oriented SA shrapnel
G'day Göran, My understanding (and I could be wrong here?) was that most Sikhote-Alin shrapnel was formed when the piece/s detonated in the air during its fall. Mike's piece is probably a good example of showing how the forces/pressure on that piece grew to such a point, the structure of the meteorite (coarsest octahedrite) was no longer able to support it. Cheers, Jeff - Original Message - From: Göran Axelsson To: meteorite-list@meteoritecentral.com Sent: Wednesday, August 10, 2005 9:42 AM Subject: Re: [meteorite-list] Question on oriented SA shrapnel I was looking through some of Michael Farmers auctions on Ebay and one piece made me puzzled. It was a 7 kg oriented Sikhote-Alin that had flowlines. I thought that all the shrapnel pieces were created when larger meteorites impacted and tore the metal apart. But flowlines should mean that this shrapnel were created in flight. My question is if there are shrapnel pieces created in flight? I have a neat oriented Sikhote-Alin in my collection, complete with flowlines, thumbprinting and even fractured surfaces and teared metal. It isn't a shrapnel and there still are some crust on the leading edge with finer flowlines in the crust. If a shrapnel piece would have crust with flowlines then I would be convinced that it was created in flight but isn't it possible that there could be similar structures without crust created when it hits the ground? I'm just curious as this is the first shrapnel I've heard about with flowlines. Regards, Göran Michael Farmer wrote: I have loaded another 53 meteorites on ebay, most starting at... -- snipp -- 7 kilo ORIENTED Sikhote-Alin piece. $4000.00 specimen, up for one cent. http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItemrd=1item=6551087736 -- snip -- Mike Farmer __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
