Re: [meteorite-list] Chelyabinsk - slickensides or shock planes?
Morning Jim How, you ask? Take two large meteoroids and wack them together at incredible speeds. What is not vaporized or pulverized will sheer and move in an opposite vector to relieve compressional forces where the two meteoroids interfaced. The compression varies according to the macro surface: where there are ridges/bumps on one body, the other body at that junction will see more compressional force and where there are valleys one will see less compressional and vice versa. The rupture of the matrix is nature's way of balancing the competition for space and the kinetic energy vectors: the inertia thingy. We know it as equal and opposite reactions. Since silicate is not elastic, it will break and areas of it will be displaced relative to the other side of the fracture. Since the rupture is rarely even, the two sides will grind against each other leaving skid marks all other things considered. Both the energy and masses have to return to balance after the impact. Slickensides represent areas of the original body where sheer exceeds physical bonds and will be displaced to accommodate the compression forces(solids don't compress but they do respond to compressional forces) Elton From: Jim Wooddell jim.woodd...@suddenlink.net To: meteorite-list@meteoritecentral.com Sent: Wednesday, May 22, 2013 8:31 AM Subject: Re: [meteorite-list] Chelyabinsk - slickensides or shock planes? Good morning all! Can anyone explain to me how slickensides are created in bonded matrix in space in only minute areas of a large body? Thanks! Jim Wooddell __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chelyabinsk - slickensides or shock planes?
Yes it is. A very famous meteorite that shows great slickensides is Zag actually. Have all a great day! Frederic Beroud www.meteoriteshow.com IMCA #2491 -Message d'origine- De : meteorite-list-boun...@meteoritecentral.com [mailto:meteorite-list-boun...@meteoritecentral.com] De la part de Anne Black Envoyé : mardi 21 mai 2013 23:03 À : jim.woodd...@suddenlink.net; meteorite-list@meteoritecentral.com Objet : Re: [meteorite-list] Chelyabinsk - slickensides or shock planes? Does this help Jim? http://www.impactika.com/CH-126slick.jpg To me, slickensides look almost like streaks, and yes, shiny. Like my cat scratched it! ;-) Anne M. Black www.IMPACTIKA.com impact...@aol.com -Original Message- From: Jim Wooddell jim.woodd...@suddenlink.net To: meteorite-list meteorite-list@meteoritecentral.com Sent: Tue, May 21, 2013 2:08 pm Subject: Re: [meteorite-list] Chelyabinsk - slickensides or shock planes? Welp, I just need to see one up close. But in the mean time here is a paper on the subject that may be of interest... http://adsabs.harvard.edu/full/1966Metic...3...31D Jim On 5/21/2013 10:26 AM, Michael Farmer wrote: Jim, there are shock veins and slickensides. They are not the same thing. They are result of shock but not melting like the full melt veins are. I have hundreds of pieces with slickensides. I am traveling so I can't show photos. Perhaps later. Michael Farmer Sent from my iPhone On May 21, 2013, at 12:19 PM, Jim Wooddell jim.woodd...@suddenlink.net wrote: Hi Jim Baxter, And, that is what I am not seeing. I'am going to be a very hard sell on the term slickensides until I see something that scientifically supports it and why it is there. Do the threads actually appear and are they threads?? In my mind, the coming apart part would not create a slickenside (cool state) where as the coming together with great pressure and time would. Just thinking out loud, not qualified to say one way or the other! I also see where this appearance is shown lower in topography in it's area which, to me, would be odd for slickenside. Cheers! Jim Wooddell On 5/21/2013 9:18 AM, Jim Baxter wrote: Slickensides are polished surfaces caused by lateral movement along a fault plane. In hand specimens they feel rough when you rub your finger in one direction and smooth when you rub it in the other. Not sure that test would be feasible on the size specimens most of us own. In theory if the fault planes represent planes of weakness along which breaks occur then you could be seeing both things - slickensides that formed by lateral movement along the shock plane when the stone fractured. Jim Baxter __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list - No virus found in this message. Checked by AVG - www.avg.com Version: 2013.0.3343 / Virus Database: 3162/6344 - Release Date: 05/21/13 __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chelyabinsk - slickensides or shock planes?
I've also seen them in the Ochansk meteorite. Thanks, Derek. Meteoriteshow meteorites...@free.fr wrote: Yes it is. A very famous meteorite that shows great slickensides is Zag actually. Have all a great day! Frederic Beroud www.meteoriteshow.com IMCA #2491 -Message d'origine- De : meteorite-list-boun...@meteoritecentral.com [mailto:meteorite-list-boun...@meteoritecentral.com] De la part de Anne Black Envoyé : mardi 21 mai 2013 23:03 À : jim.woodd...@suddenlink.net; meteorite-list@meteoritecentral.com Objet : Re: [meteorite-list] Chelyabinsk - slickensides or shock planes? Does this help Jim? http://www.impactika.com/CH-126slick.jpg To me, slickensides look almost like streaks, and yes, shiny. Like my cat scratched it! ;-) Anne M. Black www.IMPACTIKA.com impact...@aol.com -Original Message- From: Jim Wooddell jim.woodd...@suddenlink.net To: meteorite-list meteorite-list@meteoritecentral.com Sent: Tue, May 21, 2013 2:08 pm Subject: Re: [meteorite-list] Chelyabinsk - slickensides or shock planes? Welp, I just need to see one up close. But in the mean time here is a paper on the subject that may be of interest... http://adsabs.harvard.edu/full/1966Metic...3...31D Jim On 5/21/2013 10:26 AM, Michael Farmer wrote: Jim, there are shock veins and slickensides. They are not the same thing. They are result of shock but not melting like the full melt veins are. I have hundreds of pieces with slickensides. I am traveling so I can't show photos. Perhaps later. Michael Farmer Sent from my iPhone On May 21, 2013, at 12:19 PM, Jim Wooddell jim.woodd...@suddenlink.net wrote: Hi Jim Baxter, And, that is what I am not seeing. I'am going to be a very hard sell on the term slickensides until I see something that scientifically supports it and why it is there. Do the threads actually appear and are they threads?? In my mind, the coming apart part would not create a slickenside (cool state) where as the coming together with great pressure and time would. Just thinking out loud, not qualified to say one way or the other! I also see where this appearance is shown lower in topography in it's area which, to me, would be odd for slickenside. Cheers! Jim Wooddell On 5/21/2013 9:18 AM, Jim Baxter wrote: Slickensides are polished surfaces caused by lateral movement along a fault plane. In hand specimens they feel rough when you rub your finger in one direction and smooth when you rub it in the other. Not sure that test would be feasible on the size specimens most of us own. In theory if the fault planes represent planes of weakness along which breaks occur then you could be seeing both things - slickensides that formed by lateral movement along the shock plane when the stone fractured. Jim Baxter __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list - No virus found in this message. Checked by AVG - www.avg.com Version: 2013.0.3343 / Virus Database: 3162/6344 - Release Date: 05/21/13 __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chelyabinsk - slickensides or shock planes?
Good morning all! Can anyone explain to me how slickensides are created in bonded matrix in space in only minute areas of a large body? Thanks! Jim Wooddell __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chelyabinsk - slickensides or shock planes?
Since the reference to slickensides has been a topic recently, I thought some would be interested in this nice example I just found being offered on eBay. It shows the feature very well. http://www.ebay.com/itm/HUGE-FIREBALL-NEWEST-FALL-SLICKENSIDE-FRAGMENT-CHELYABINSK-METEORITE-22-5-GM-/190831604603?pt=LH_DefaultDomain_0hash=item2c6e73337b Mal IMCA#6819 __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chelyabinsk - slickensides or shock planes?
I'm not so sure this picture shows slickensides...if you look closely at the picture there are veins of melt running from the black areaI think it is just a break through one of the large melt pockets that are evident in Chelyabinsk.it does have the look of a slickenside but they are just paper thin black melt sheets scored in one direction and would not have thicker melt veins coming from them. Graham On Wed, May 22, 2013 at 2:17 PM, Malvin Bishop Jr magbi...@lowcountry.com wrote: Since the reference to slickensides has been a topic recently, I thought some would be interested in this nice example I just found being offered on eBay. It shows the feature very well. http://www.ebay.com/itm/HUGE-FIREBALL-NEWEST-FALL-SLICKENSIDE-FRAGMENT-CHELYABINSK-METEORITE-22-5-GM-/190831604603?pt=LH_DefaultDomain_0hash=item2c6e73337b Mal IMCA#6819 __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chelyabinsk - slickensides or shock planes?
Hi Bob and all! I might be wrong in assuming, but your slickensides sounds like you are attempting to describe secondary fusion??? We have lots of evidence in various meteorites where they broke apart for whatever reason at the weak boundaries. For example, Franconia area meteorites (some) break apart from both sides of a metal vein leaving three pieces...two chondrite fragments and an H-Metal cornflake. It's sort of like looking at a bad weld through xray. How can you tell? Look at more and look closer. A 3D CT sort of scan that has become popular with Sutter's Mill or Dr. Agee's research on Black Beauty may reveal what you speak of. Just my thoughts. Kind Regards, Jim On Tue, May 21, 2013 at 7:06 AM, Bob King nightsk...@gmail.com wrote: Hi everyone, Many pieces of broken Chelyabinsk specimens display what appears like fusion crust over slickensides, but is that what it really is? I've talked with Blaine Reed and he thinks we're seeing blackish shock veins (planes really) where the meteorite split along a line of weakness. He even mentioned a piece he's seen where a large shock vein in the matrix leads directly to the broken, dark face. Assuming Chelyabinsk shows both slickensides and shock vein planes, how do you tell them apart? Thanks for your thoughts. Bob __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list -- Jim Wooddell jimwoodd...@gmail.com 928-247-2675 __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chelyabinsk - slickensides or shock planes?
Hi Bob, Jim, and list - One of my Chelyabinsk specimens shows a feature where it appears to be fractured along a weakened shock vein/point where melt had filled the vein before the actual splitting apart. The melt is still very evident covering a large portion of the fresh exposed matrix after the specimen split in two. In short, I tend to agree with Blaine. Regards, Mal On 5/21/2013 10:29 AM, Jim Wooddell wrote: Hi Bob and all! I might be wrong in assuming, but your slickensides sounds like you are attempting to describe secondary fusion??? We have lots of evidence in various meteorites where they broke apart for whatever reason at the weak boundaries. For example, Franconia area meteorites (some) break apart from both sides of a metal vein leaving three pieces...two chondrite fragments and an H-Metal cornflake. It's sort of like looking at a bad weld through xray. How can you tell? Look at more and look closer. A 3D CT sort of scan that has become popular with Sutter's Mill or Dr. Agee's research on Black Beauty may reveal what you speak of. Just my thoughts. Kind Regards, Jim On Tue, May 21, 2013 at 7:06 AM, Bob King nightsk...@gmail.com wrote: Hi everyone, Many pieces of broken Chelyabinsk specimens display what appears like fusion crust over slickensides, but is that what it really is? I've talked with Blaine Reed and he thinks we're seeing blackish shock veins (planes really) where the meteorite split along a line of weakness. He even mentioned a piece he's seen where a large shock vein in the matrix leads directly to the broken, dark face. Assuming Chelyabinsk shows both slickensides and shock vein planes, how do you tell them apart? Thanks for your thoughts. Bob __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chelyabinsk - slickensides or shock planes?
Hi Jim, Thanks for your reply. No, what I'm seeing is different from the secondary fusion crusts I typically see, and it's nearly identical on many pieces. The broken faces have a planar, slickenside texture and appear coated with gray material that's either fusion crust or as Blaine thinks, an exposed shock plane. Bob On Tue, May 21, 2013 at 9:29 AM, Jim Wooddell jimwoodd...@gmail.com wrote: Hi Bob and all! I might be wrong in assuming, but your slickensides sounds like you are attempting to describe secondary fusion??? We have lots of evidence in various meteorites where they broke apart for whatever reason at the weak boundaries. For example, Franconia area meteorites (some) break apart from both sides of a metal vein leaving three pieces...two chondrite fragments and an H-Metal cornflake. It's sort of like looking at a bad weld through xray. How can you tell? Look at more and look closer. A 3D CT sort of scan that has become popular with Sutter's Mill or Dr. Agee's research on Black Beauty may reveal what you speak of. Just my thoughts. Kind Regards, Jim On Tue, May 21, 2013 at 7:06 AM, Bob King nightsk...@gmail.com wrote: Hi everyone, Many pieces of broken Chelyabinsk specimens display what appears like fusion crust over slickensides, but is that what it really is? I've talked with Blaine Reed and he thinks we're seeing blackish shock veins (planes really) where the meteorite split along a line of weakness. He even mentioned a piece he's seen where a large shock vein in the matrix leads directly to the broken, dark face. Assuming Chelyabinsk shows both slickensides and shock vein planes, how do you tell them apart? Thanks for your thoughts. Bob __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list -- Jim Wooddell jimwoodd...@gmail.com 928-247-2675 __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chelyabinsk - slickensides or shock planes?
Bob, Jim, List, I have a small piece that displays the slickenside in 3 distinct locations; it's definitely not secondary fusion crust. Looking forward to hearing more on the subject. Michael in so. Cal. On Tue, May 21, 2013 at 7:29 AM, Jim Wooddell jimwoodd...@gmail.com wrote: Hi Bob and all! I might be wrong in assuming, but your slickensides sounds like you are attempting to describe secondary fusion??? We have lots of evidence in various meteorites where they broke apart for whatever reason at the weak boundaries. For example, Franconia area meteorites (some) break apart from both sides of a metal vein leaving three pieces...two chondrite fragments and an H-Metal cornflake. It's sort of like looking at a bad weld through xray. How can you tell? Look at more and look closer. A 3D CT sort of scan that has become popular with Sutter's Mill or Dr. Agee's research on Black Beauty may reveal what you speak of. Just my thoughts. Kind Regards, Jim On Tue, May 21, 2013 at 7:06 AM, Bob King nightsk...@gmail.com wrote: Hi everyone, Many pieces of broken Chelyabinsk specimens display what appears like fusion crust over slickensides, but is that what it really is? I've talked with Blaine Reed and he thinks we're seeing blackish shock veins (planes really) where the meteorite split along a line of weakness. He even mentioned a piece he's seen where a large shock vein in the matrix leads directly to the broken, dark face. Assuming Chelyabinsk shows both slickensides and shock vein planes, how do you tell them apart? Thanks for your thoughts. Bob __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list -- Jim Wooddell jimwoodd...@gmail.com 928-247-2675 __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chelyabinsk - slickensides or shock planes?
Michael and all, I forgot to add that even small 2-3g Chelyabinsks show this same slick, grey material coating their broken faces. Can slickensides form on rocks this small? Bob On Tue, May 21, 2013 at 9:43 AM, Michael Mulgrew mikest...@gmail.com wrote: Bob, Jim, List, I have a small piece that displays the slickenside in 3 distinct locations; it's definitely not secondary fusion crust. Looking forward to hearing more on the subject. Michael in so. Cal. On Tue, May 21, 2013 at 7:29 AM, Jim Wooddell jimwoodd...@gmail.com wrote: Hi Bob and all! I might be wrong in assuming, but your slickensides sounds like you are attempting to describe secondary fusion??? We have lots of evidence in various meteorites where they broke apart for whatever reason at the weak boundaries. For example, Franconia area meteorites (some) break apart from both sides of a metal vein leaving three pieces...two chondrite fragments and an H-Metal cornflake. It's sort of like looking at a bad weld through xray. How can you tell? Look at more and look closer. A 3D CT sort of scan that has become popular with Sutter's Mill or Dr. Agee's research on Black Beauty may reveal what you speak of. Just my thoughts. Kind Regards, Jim On Tue, May 21, 2013 at 7:06 AM, Bob King nightsk...@gmail.com wrote: Hi everyone, Many pieces of broken Chelyabinsk specimens display what appears like fusion crust over slickensides, but is that what it really is? I've talked with Blaine Reed and he thinks we're seeing blackish shock veins (planes really) where the meteorite split along a line of weakness. He even mentioned a piece he's seen where a large shock vein in the matrix leads directly to the broken, dark face. Assuming Chelyabinsk shows both slickensides and shock vein planes, how do you tell them apart? Thanks for your thoughts. Bob __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list -- Jim Wooddell jimwoodd...@gmail.com 928-247-2675 __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chelyabinsk - slickensides or shock planes?
Bob, My piece is just over 5g, but it was broken off a slightly larger piece, probably less than 50g before it broke. Michael in so. Cal. On Tue, May 21, 2013 at 7:48 AM, Bob King nightsk...@gmail.com wrote: Michael and all, I forgot to add that even small 2-3g Chelyabinsks show this same slick, grey material coating their broken faces. Can slickensides form on rocks this small? Bob On Tue, May 21, 2013 at 9:43 AM, Michael Mulgrew mikest...@gmail.com wrote: Bob, Jim, List, I have a small piece that displays the slickenside in 3 distinct locations; it's definitely not secondary fusion crust. Looking forward to hearing more on the subject. Michael in so. Cal. On Tue, May 21, 2013 at 7:29 AM, Jim Wooddell jimwoodd...@gmail.com wrote: Hi Bob and all! I might be wrong in assuming, but your slickensides sounds like you are attempting to describe secondary fusion??? We have lots of evidence in various meteorites where they broke apart for whatever reason at the weak boundaries. For example, Franconia area meteorites (some) break apart from both sides of a metal vein leaving three pieces...two chondrite fragments and an H-Metal cornflake. It's sort of like looking at a bad weld through xray. How can you tell? Look at more and look closer. A 3D CT sort of scan that has become popular with Sutter's Mill or Dr. Agee's research on Black Beauty may reveal what you speak of. Just my thoughts. Kind Regards, Jim On Tue, May 21, 2013 at 7:06 AM, Bob King nightsk...@gmail.com wrote: Hi everyone, Many pieces of broken Chelyabinsk specimens display what appears like fusion crust over slickensides, but is that what it really is? I've talked with Blaine Reed and he thinks we're seeing blackish shock veins (planes really) where the meteorite split along a line of weakness. He even mentioned a piece he's seen where a large shock vein in the matrix leads directly to the broken, dark face. Assuming Chelyabinsk shows both slickensides and shock vein planes, how do you tell them apart? Thanks for your thoughts. Bob __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list -- Jim Wooddell jimwoodd...@gmail.com 928-247-2675 __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chelyabinsk - slickensides or shock planes?
Hi All, Look at the two pictures of the same stone. This is a fresh broken side with black shock veins on a very light matrix: - http://sv-meteorites.com/gallery/chelybinsk/02.jpg And this side is secondary crust over the shock vein: - http://sv-meteorites.com/gallery/chelybinsk/01.jpg You can find a lot of interesting things in Chelyabinsk ;-) All the best, Sergey On Tue, May 21, 2013 at 4:59 PM, Michael Mulgrew mikest...@gmail.com wrote: Bob, My piece is just over 5g, but it was broken off a slightly larger piece, probably less than 50g before it broke. Michael in so. Cal. On Tue, May 21, 2013 at 7:48 AM, Bob King nightsk...@gmail.com wrote: Michael and all, I forgot to add that even small 2-3g Chelyabinsks show this same slick, grey material coating their broken faces. Can slickensides form on rocks this small? Bob On Tue, May 21, 2013 at 9:43 AM, Michael Mulgrew mikest...@gmail.com wrote: Bob, Jim, List, I have a small piece that displays the slickenside in 3 distinct locations; it's definitely not secondary fusion crust. Looking forward to hearing more on the subject. Michael in so. Cal. On Tue, May 21, 2013 at 7:29 AM, Jim Wooddell jimwoodd...@gmail.com wrote: Hi Bob and all! I might be wrong in assuming, but your slickensides sounds like you are attempting to describe secondary fusion??? We have lots of evidence in various meteorites where they broke apart for whatever reason at the weak boundaries. For example, Franconia area meteorites (some) break apart from both sides of a metal vein leaving three pieces...two chondrite fragments and an H-Metal cornflake. It's sort of like looking at a bad weld through xray. How can you tell? Look at more and look closer. A 3D CT sort of scan that has become popular with Sutter's Mill or Dr. Agee's research on Black Beauty may reveal what you speak of. Just my thoughts. Kind Regards, Jim On Tue, May 21, 2013 at 7:06 AM, Bob King nightsk...@gmail.com wrote: Hi everyone, Many pieces of broken Chelyabinsk specimens display what appears like fusion crust over slickensides, but is that what it really is? I've talked with Blaine Reed and he thinks we're seeing blackish shock veins (planes really) where the meteorite split along a line of weakness. He even mentioned a piece he's seen where a large shock vein in the matrix leads directly to the broken, dark face. Assuming Chelyabinsk shows both slickensides and shock vein planes, how do you tell them apart? Thanks for your thoughts. Bob __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list -- Jim Wooddell jimwoodd...@gmail.com 928-247-2675 __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chelyabinsk - slickensides or shock planes?
I've noticed the same thing... I think this is a laterally exposed shock vein... sometimes they are crusted over, other times they are pretty fresh, so you can see the size of the exposed plane... http://www.fallingrocks.com/Collections/Chelyabinsk.htm (4th picture down, top left of photo...) It's hard to take a picture of because it is so reflective, but it it quite a beautiful feature of this fall. Sean. -Original Message- From: Sergey Vasiliev Sent: Tuesday, May 21, 2013 11:16 AM To: Michael Mulgrew Cc: meteorite list Subject: Re: [meteorite-list] Chelyabinsk - slickensides or shock planes? Hi All, Look at the two pictures of the same stone. This is a fresh broken side with black shock veins on a very light matrix: - http://sv-meteorites.com/gallery/chelybinsk/02.jpg And this side is secondary crust over the shock vein: - http://sv-meteorites.com/gallery/chelybinsk/01.jpg You can find a lot of interesting things in Chelyabinsk ;-) All the best, Sergey On Tue, May 21, 2013 at 4:59 PM, Michael Mulgrew mikest...@gmail.com wrote: Bob, My piece is just over 5g, but it was broken off a slightly larger piece, probably less than 50g before it broke. Michael in so. Cal. On Tue, May 21, 2013 at 7:48 AM, Bob King nightsk...@gmail.com wrote: Michael and all, I forgot to add that even small 2-3g Chelyabinsks show this same slick, grey material coating their broken faces. Can slickensides form on rocks this small? Bob On Tue, May 21, 2013 at 9:43 AM, Michael Mulgrew mikest...@gmail.com wrote: Bob, Jim, List, I have a small piece that displays the slickenside in 3 distinct locations; it's definitely not secondary fusion crust. Looking forward to hearing more on the subject. Michael in so. Cal. On Tue, May 21, 2013 at 7:29 AM, Jim Wooddell jimwoodd...@gmail.com wrote: Hi Bob and all! I might be wrong in assuming, but your slickensides sounds like you are attempting to describe secondary fusion??? We have lots of evidence in various meteorites where they broke apart for whatever reason at the weak boundaries. For example, Franconia area meteorites (some) break apart from both sides of a metal vein leaving three pieces...two chondrite fragments and an H-Metal cornflake. It's sort of like looking at a bad weld through xray. How can you tell? Look at more and look closer. A 3D CT sort of scan that has become popular with Sutter's Mill or Dr. Agee's research on Black Beauty may reveal what you speak of. Just my thoughts. Kind Regards, Jim On Tue, May 21, 2013 at 7:06 AM, Bob King nightsk...@gmail.com wrote: Hi everyone, Many pieces of broken Chelyabinsk specimens display what appears like fusion crust over slickensides, but is that what it really is? I've talked with Blaine Reed and he thinks we're seeing blackish shock veins (planes really) where the meteorite split along a line of weakness. He even mentioned a piece he's seen where a large shock vein in the matrix leads directly to the broken, dark face. Assuming Chelyabinsk shows both slickensides and shock vein planes, how do you tell them apart? Thanks for your thoughts. Bob __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list -- Jim Wooddell jimwoodd...@gmail.com 928-247-2675 __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chelyabinsk - slickensides or shock planes?
Hi Sergey, Those are nice pictures. I see the secondary, I do not see slickenside. I decided to take a look at all the samples for sale on Ebay. There is a fellow there selling slickenside fragments. Even with those, I say look closer. I imagine you have been very busy! That's a good thing! Cheers! Jim Wooddell On 5/21/2013 8:16 AM, Sergey Vasiliev wrote: Hi All, Look at the two pictures of the same stone. This is a fresh broken side with black shock veins on a very light matrix: - http://sv-meteorites.com/gallery/chelybinsk/02.jpg And this side is secondary crust over the shock vein: - http://sv-meteorites.com/gallery/chelybinsk/01.jpg You can find a lot of interesting things in Chelyabinsk ;-) All the best, Sergey __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chelyabinsk - slickensides or shock planes?
Hi Jim, There is a slickensides there, but very difficult to make a picture of it because of reflection. Best regards, Sergey On Tue, May 21, 2013 at 5:32 PM, Jim Wooddell jim.woodd...@suddenlink.net wrote: Hi Sergey, Those are nice pictures. I see the secondary, I do not see slickenside. I decided to take a look at all the samples for sale on Ebay. There is a fellow there selling slickenside fragments. Even with those, I say look closer. I imagine you have been very busy! That's a good thing! Cheers! Jim Wooddell On 5/21/2013 8:16 AM, Sergey Vasiliev wrote: Hi All, Look at the two pictures of the same stone. This is a fresh broken side with black shock veins on a very light matrix: - http://sv-meteorites.com/gallery/chelybinsk/02.jpg And this side is secondary crust over the shock vein: - http://sv-meteorites.com/gallery/chelybinsk/01.jpg You can find a lot of interesting things in Chelyabinsk ;-) All the best, Sergey __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chelyabinsk - slickensides or shock planes?
Chelyabinsk is an incredible meteorite with so many lithologies and variations, it is almost unlike any meteorite I have ever seen. You can have 5 pieces side by side and swear all are from different meteorite falls. Some pieces are hardly recognizable as meteorites. Many pieces exhibit amazing slickensides and most of the fragmented pieces broke along those planes. Don't forget, virtually nothing broke on impact, it was all in the massive disruptions in flight that created uncountable fragments and individuals. The impact-melt material is basically Cat Mountain without the metal. The shock-melt pieces with huge glass veins are breathtaking when sliced. Most oriented pieces are small, though a couple large ones were found. One sitting beside me at this moment:) No meteorite collection will be complete if it lacks Chelyabinsk, especially Binsk Berries. Michael Farmer On May 21, 2013, at 10:36 AM, Sergey Vasiliev vs.petrov...@gmail.com wrote: Hi Jim, There is a slickensides there, but very difficult to make a picture of it because of reflection. Best regards, Sergey On Tue, May 21, 2013 at 5:32 PM, Jim Wooddell jim.woodd...@suddenlink.net wrote: Hi Sergey, Those are nice pictures. I see the secondary, I do not see slickenside. I decided to take a look at all the samples for sale on Ebay. There is a fellow there selling slickenside fragments. Even with those, I say look closer. I imagine you have been very busy! That's a good thing! Cheers! Jim Wooddell On 5/21/2013 8:16 AM, Sergey Vasiliev wrote: Hi All, Look at the two pictures of the same stone. This is a fresh broken side with black shock veins on a very light matrix: - http://sv-meteorites.com/gallery/chelybinsk/02.jpg And this side is secondary crust over the shock vein: - http://sv-meteorites.com/gallery/chelybinsk/01.jpg You can find a lot of interesting things in Chelyabinsk ;-) All the best, Sergey __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chelyabinsk - slickensides or shock planes?
Hi Sean, That photo shows it exactly! Thanks, Bob On Tue, May 21, 2013 at 10:24 AM, Sean T. Murray s...@bellsouth.net wrote: I've noticed the same thing... I think this is a laterally exposed shock vein... sometimes they are crusted over, other times they are pretty fresh, so you can see the size of the exposed plane... http://www.fallingrocks.com/Collections/Chelyabinsk.htm (4th picture down, top left of photo...) It's hard to take a picture of because it is so reflective, but it it quite a beautiful feature of this fall. Sean. -Original Message- From: Sergey Vasiliev Sent: Tuesday, May 21, 2013 11:16 AM To: Michael Mulgrew Cc: meteorite list Subject: Re: [meteorite-list] Chelyabinsk - slickensides or shock planes? Hi All, Look at the two pictures of the same stone. This is a fresh broken side with black shock veins on a very light matrix: - http://sv-meteorites.com/gallery/chelybinsk/02.jpg And this side is secondary crust over the shock vein: - http://sv-meteorites.com/gallery/chelybinsk/01.jpg You can find a lot of interesting things in Chelyabinsk ;-) All the best, Sergey On Tue, May 21, 2013 at 4:59 PM, Michael Mulgrew mikest...@gmail.com wrote: Bob, My piece is just over 5g, but it was broken off a slightly larger piece, probably less than 50g before it broke. Michael in so. Cal. On Tue, May 21, 2013 at 7:48 AM, Bob King nightsk...@gmail.com wrote: Michael and all, I forgot to add that even small 2-3g Chelyabinsks show this same slick, grey material coating their broken faces. Can slickensides form on rocks this small? Bob On Tue, May 21, 2013 at 9:43 AM, Michael Mulgrew mikest...@gmail.com wrote: Bob, Jim, List, I have a small piece that displays the slickenside in 3 distinct locations; it's definitely not secondary fusion crust. Looking forward to hearing more on the subject. Michael in so. Cal. On Tue, May 21, 2013 at 7:29 AM, Jim Wooddell jimwoodd...@gmail.com wrote: Hi Bob and all! I might be wrong in assuming, but your slickensides sounds like you are attempting to describe secondary fusion??? We have lots of evidence in various meteorites where they broke apart for whatever reason at the weak boundaries. For example, Franconia area meteorites (some) break apart from both sides of a metal vein leaving three pieces...two chondrite fragments and an H-Metal cornflake. It's sort of like looking at a bad weld through xray. How can you tell? Look at more and look closer. A 3D CT sort of scan that has become popular with Sutter's Mill or Dr. Agee's research on Black Beauty may reveal what you speak of. Just my thoughts. Kind Regards, Jim On Tue, May 21, 2013 at 7:06 AM, Bob King nightsk...@gmail.com wrote: Hi everyone, Many pieces of broken Chelyabinsk specimens display what appears like fusion crust over slickensides, but is that what it really is? I've talked with Blaine Reed and he thinks we're seeing blackish shock veins (planes really) where the meteorite split along a line of weakness. He even mentioned a piece he's seen where a large shock vein in the matrix leads directly to the broken, dark face. Assuming Chelyabinsk shows both slickensides and shock vein planes, how do you tell them apart? Thanks for your thoughts. Bob __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list -- Jim Wooddell jimwoodd...@gmail.com 928-247-2675 __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chelyabinsk - slickensides or shock planes?
Not really a good focus (try full screen!) but at the end you can see both: slickensides and crust over it on the smaller surface. http://www.youtube.com/watch?v=IVnerr2giL0feature=youtu.be Reagrds, Sergey On Tue, May 21, 2013 at 5:43 PM, Michael Farmer m...@meteoriteguy.com wrote: Chelyabinsk is an incredible meteorite with so many lithologies and variations, it is almost unlike any meteorite I have ever seen. You can have 5 pieces side by side and swear all are from different meteorite falls. Some pieces are hardly recognizable as meteorites. Many pieces exhibit amazing slickensides and most of the fragmented pieces broke along those planes. Don't forget, virtually nothing broke on impact, it was all in the massive disruptions in flight that created uncountable fragments and individuals. The impact-melt material is basically Cat Mountain without the metal. The shock-melt pieces with huge glass veins are breathtaking when sliced. Most oriented pieces are small, though a couple large ones were found. One sitting beside me at this moment:) No meteorite collection will be complete if it lacks Chelyabinsk, especially Binsk Berries. Michael Farmer On May 21, 2013, at 10:36 AM, Sergey Vasiliev vs.petrov...@gmail.com wrote: Hi Jim, There is a slickensides there, but very difficult to make a picture of it because of reflection. Best regards, Sergey On Tue, May 21, 2013 at 5:32 PM, Jim Wooddell jim.woodd...@suddenlink.net wrote: Hi Sergey, Those are nice pictures. I see the secondary, I do not see slickenside. I decided to take a look at all the samples for sale on Ebay. There is a fellow there selling slickenside fragments. Even with those, I say look closer. I imagine you have been very busy! That's a good thing! Cheers! Jim Wooddell On 5/21/2013 8:16 AM, Sergey Vasiliev wrote: Hi All, Look at the two pictures of the same stone. This is a fresh broken side with black shock veins on a very light matrix: - http://sv-meteorites.com/gallery/chelybinsk/02.jpg And this side is secondary crust over the shock vein: - http://sv-meteorites.com/gallery/chelybinsk/01.jpg You can find a lot of interesting things in Chelyabinsk ;-) All the best, Sergey __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chelyabinsk - slickensides or shock planes?
Hi Bob and all! When I think slickenside, I think of a polished surface where something rubbed on the surface to polish it. I don't see this in any of the pictures. My samples do not have thisso I guess I will have to just buy some more!!! Very interesting. What do you guys suppose did this? It would not have had anything to do with the break up, I suppose. Jim On 5/21/2013 8:48 AM, Bob King wrote: Hi Sean, That photo shows it exactly! Thanks, Bob __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chelyabinsk - slickensides or shock planes?
Hi Jim Baxter, And, that is what I am not seeing. I'am going to be a very hard sell on the term slickensides until I see something that scientifically supports it and why it is there. Do the threads actually appear and are they threads?? In my mind, the coming apart part would not create a slickenside (cool state) where as the coming together with great pressure and time would. Just thinking out loud, not qualified to say one way or the other! I also see where this appearance is shown lower in topography in it's area which, to me, would be odd for slickenside. Cheers! Jim Wooddell On 5/21/2013 9:18 AM, Jim Baxter wrote: Slickensides are polished surfaces caused by lateral movement along a fault plane. In hand specimens they feel rough when you rub your finger in one direction and smooth when you rub it in the other. Not sure that test would be feasible on the size specimens most of us own. In theory if the fault planes represent planes of weakness along which breaks occur then you could be seeing both things - slickensides that formed by lateral movement along the shock plane when the stone fractured. Jim Baxter __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chelyabinsk - slickensides or shock planes?
Jim, there are shock veins and slickensides. They are not the same thing. They are result of shock but not melting like the full melt veins are. I have hundreds of pieces with slickensides. I am traveling so I can't show photos. Perhaps later. Michael Farmer Sent from my iPhone On May 21, 2013, at 12:19 PM, Jim Wooddell jim.woodd...@suddenlink.net wrote: Hi Jim Baxter, And, that is what I am not seeing. I'am going to be a very hard sell on the term slickensides until I see something that scientifically supports it and why it is there. Do the threads actually appear and are they threads?? In my mind, the coming apart part would not create a slickenside (cool state) where as the coming together with great pressure and time would. Just thinking out loud, not qualified to say one way or the other! I also see where this appearance is shown lower in topography in it's area which, to me, would be odd for slickenside. Cheers! Jim Wooddell On 5/21/2013 9:18 AM, Jim Baxter wrote: Slickensides are polished surfaces caused by lateral movement along a fault plane. In hand specimens they feel rough when you rub your finger in one direction and smooth when you rub it in the other. Not sure that test would be feasible on the size specimens most of us own. In theory if the fault planes represent planes of weakness along which breaks occur then you could be seeing both things - slickensides that formed by lateral movement along the shock plane when the stone fractured. Jim Baxter __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chelyabinsk - slickensides or shock planes?
hi Bobto my knowledge the slickensides most likely form in the original asteroidal body in space (large collision or impact) and then are left in the small stones after the atmospheric breakup. Graham On Tue, May 21, 2013 at 3:48 PM, Bob King nightsk...@gmail.com wrote: Michael and all, I forgot to add that even small 2-3g Chelyabinsks show this same slick, grey material coating their broken faces. Can slickensides form on rocks this small? Bob On Tue, May 21, 2013 at 9:43 AM, Michael Mulgrew mikest...@gmail.com wrote: Bob, Jim, List, I have a small piece that displays the slickenside in 3 distinct locations; it's definitely not secondary fusion crust. Looking forward to hearing more on the subject. Michael in so. Cal. On Tue, May 21, 2013 at 7:29 AM, Jim Wooddell jimwoodd...@gmail.com wrote: Hi Bob and all! I might be wrong in assuming, but your slickensides sounds like you are attempting to describe secondary fusion??? We have lots of evidence in various meteorites where they broke apart for whatever reason at the weak boundaries. For example, Franconia area meteorites (some) break apart from both sides of a metal vein leaving three pieces...two chondrite fragments and an H-Metal cornflake. It's sort of like looking at a bad weld through xray. How can you tell? Look at more and look closer. A 3D CT sort of scan that has become popular with Sutter's Mill or Dr. Agee's research on Black Beauty may reveal what you speak of. Just my thoughts. Kind Regards, Jim On Tue, May 21, 2013 at 7:06 AM, Bob King nightsk...@gmail.com wrote: Hi everyone, Many pieces of broken Chelyabinsk specimens display what appears like fusion crust over slickensides, but is that what it really is? I've talked with Blaine Reed and he thinks we're seeing blackish shock veins (planes really) where the meteorite split along a line of weakness. He even mentioned a piece he's seen where a large shock vein in the matrix leads directly to the broken, dark face. Assuming Chelyabinsk shows both slickensides and shock vein planes, how do you tell them apart? Thanks for your thoughts. Bob __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list -- Jim Wooddell jimwoodd...@gmail.com 928-247-2675 __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chelyabinsk - slickensides or shock planes?
Welp, I just need to see one up close. But in the mean time here is a paper on the subject that may be of interest... http://adsabs.harvard.edu/full/1966Metic...3...31D Jim On 5/21/2013 10:26 AM, Michael Farmer wrote: Jim, there are shock veins and slickensides. They are not the same thing. They are result of shock but not melting like the full melt veins are. I have hundreds of pieces with slickensides. I am traveling so I can't show photos. Perhaps later. Michael Farmer Sent from my iPhone On May 21, 2013, at 12:19 PM, Jim Wooddell jim.woodd...@suddenlink.net wrote: Hi Jim Baxter, And, that is what I am not seeing. I'am going to be a very hard sell on the term slickensides until I see something that scientifically supports it and why it is there. Do the threads actually appear and are they threads?? In my mind, the coming apart part would not create a slickenside (cool state) where as the coming together with great pressure and time would. Just thinking out loud, not qualified to say one way or the other! I also see where this appearance is shown lower in topography in it's area which, to me, would be odd for slickenside. Cheers! Jim Wooddell On 5/21/2013 9:18 AM, Jim Baxter wrote: Slickensides are polished surfaces caused by lateral movement along a fault plane. In hand specimens they feel rough when you rub your finger in one direction and smooth when you rub it in the other. Not sure that test would be feasible on the size specimens most of us own. In theory if the fault planes represent planes of weakness along which breaks occur then you could be seeing both things - slickensides that formed by lateral movement along the shock plane when the stone fractured. Jim Baxter __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list - No virus found in this message. Checked by AVG - www.avg.com Version: 2013.0.3343 / Virus Database: 3162/6344 - Release Date: 05/21/13 __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chelyabinsk - slickensides or shock planes?
Does this help Jim? http://www.impactika.com/CH-126slick.jpg To me, slickensides look almost like streaks, and yes, shiny. Like my cat scratched it! ;-) Anne M. Black www.IMPACTIKA.com impact...@aol.com -Original Message- From: Jim Wooddell jim.woodd...@suddenlink.net To: meteorite-list meteorite-list@meteoritecentral.com Sent: Tue, May 21, 2013 2:08 pm Subject: Re: [meteorite-list] Chelyabinsk - slickensides or shock planes? Welp, I just need to see one up close. But in the mean time here is a paper on the subject that may be of interest... http://adsabs.harvard.edu/full/1966Metic...3...31D Jim On 5/21/2013 10:26 AM, Michael Farmer wrote: Jim, there are shock veins and slickensides. They are not the same thing. They are result of shock but not melting like the full melt veins are. I have hundreds of pieces with slickensides. I am traveling so I can't show photos. Perhaps later. Michael Farmer Sent from my iPhone On May 21, 2013, at 12:19 PM, Jim Wooddell jim.woodd...@suddenlink.net wrote: Hi Jim Baxter, And, that is what I am not seeing. I'am going to be a very hard sell on the term slickensides until I see something that scientifically supports it and why it is there. Do the threads actually appear and are they threads?? In my mind, the coming apart part would not create a slickenside (cool state) where as the coming together with great pressure and time would. Just thinking out loud, not qualified to say one way or the other! I also see where this appearance is shown lower in topography in it's area which, to me, would be odd for slickenside. Cheers! Jim Wooddell On 5/21/2013 9:18 AM, Jim Baxter wrote: Slickensides are polished surfaces caused by lateral movement along a fault plane. In hand specimens they feel rough when you rub your finger in one direction and smooth when you rub it in the other. Not sure that test would be feasible on the size specimens most of us own. In theory if the fault planes represent planes of weakness along which breaks occur then you could be seeing both things - slickensides that formed by lateral movement along the shock plane when the stone fractured. Jim Baxter __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list - No virus found in this message. Checked by AVG - www.avg.com Version: 2013.0.3343 / Virus Database: 3162/6344 - Release Date: 05/21/13 __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chelyabinsk - slickensides or shock planes?
I found a very nice Chelyabinsk while running to the truck after finding a 1.2 kg stone. I saw it flash in the sun, a half stone with silver slickenside up, it was like a mirror. Michael Farmer Sent from my iPhone On May 21, 2013, at 4:36 PM, Bernd V. Pauli bernd.pa...@paulinet.de wrote: Hello All, We had a similar discussion many, many years ago (September 2001). Here's a short overview of our results: Summary: - broken surface is covered with glossy striations - slickensides are identified by shiny mirror like surfaces on an otherwise rough rock - they are the product of faulting in a rock body (as the crust shifts, even slightly, the roughness of the rock tends to smooth) - slickensides are formed from the movement of rocks relative to each other along fracture planes in fault zones - rub your finger along the grooves which make up the slickensides: * they feel rough when you move your finger in the direction opposite to which the adjacent rock moved to form the slickensides + they feel smooth when you rub in the same direction the adjacent rock moved because it sheared off any microscopic projections or rough edges as it moved = Not found in shatter cones! - slickensides are formed when opposite sides of rock faults move in different directions - extreme pressure generates frictional heat as the rock faces are forced past each other partially melting a thin veneer of rock at the interface (result: smoothing of rough edges and a polished looking surface) - they are not formed by explosive breakup in the earth's atmosphere (in such a breakup pieces would be flying apart from each other whereas in slickensides the opposite is happening: the rock faces are being forced against each other) but: see below ** - possible formation scenario: an impact event in space results in movement of two adjacent parts of the stony meteorite relative to each other along a preexisting fracture plane thus creating grooves - slickensides are polished, grooved surfaces that occur along shear planes - slickensides form along internal shear planes as opposite parts move past one another - opposite parts rub against each other, their surfaces become smoothed, lineated, and grooved - slickensides are formed when two planar sides grind past each other - slickensides can be created at the moment of breakup (not by the explosive part of this breakup but rather when two parts of the meteorite grind past each other along a pre-existing fracture – so-called shear rupturing) ** and here are some of the listees that participated in the discussion: Charlie Devine (started the discussion), Eric Olson, Robert Verish, ... to name a few. Cheers, Bernd __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chelyabinsk - slickensides or shock planes?
This is what I was referring to in my previous email regarding one of my Chelyabinsk specimens showing a feature where it appears to be fractured along a weakened shock vein/point where melt had filled the vein before the actual splitting apart. The melt is very evident. Am I thinking correctly on this Mike, Sean, or whomever wishes to respond? http://s1300.photobucket.com/user/N68830/media/Chelyabinsk_fragment_zps1a7dfce6.jpg.html Mal On 5/21/2013 11:48 AM, Bob King wrote: Hi Sean, That photo shows it exactly! Thanks, Bob On Tue, May 21, 2013 at 10:24 AM, Sean T. Murray s...@bellsouth.net wrote: I've noticed the same thing... I think this is a laterally exposed shock vein... sometimes they are crusted over, other times they are pretty fresh, so you can see the size of the exposed plane... http://www.fallingrocks.com/Collections/Chelyabinsk.htm (4th picture down, top left of photo...) It's hard to take a picture of because it is so reflective, but it it quite a beautiful feature of this fall. Sean. -Original Message- From: Sergey Vasiliev Sent: Tuesday, May 21, 2013 11:16 AM To: Michael Mulgrew Cc: meteorite list Subject: Re: [meteorite-list] Chelyabinsk - slickensides or shock planes? Hi All, Look at the two pictures of the same stone. This is a fresh broken side with black shock veins on a very light matrix: - http://sv-meteorites.com/gallery/chelybinsk/02.jpg And this side is secondary crust over the shock vein: - http://sv-meteorites.com/gallery/chelybinsk/01.jpg You can find a lot of interesting things in Chelyabinsk ;-) All the best, Sergey On Tue, May 21, 2013 at 4:59 PM, Michael Mulgrew mikest...@gmail.com wrote: Bob, My piece is just over 5g, but it was broken off a slightly larger piece, probably less than 50g before it broke. Michael in so. Cal. On Tue, May 21, 2013 at 7:48 AM, Bob King nightsk...@gmail.com wrote: Michael and all, I forgot to add that even small 2-3g Chelyabinsks show this same slick, grey material coating their broken faces. Can slickensides form on rocks this small? Bob On Tue, May 21, 2013 at 9:43 AM, Michael Mulgrew mikest...@gmail.com wrote: Bob, Jim, List, I have a small piece that displays the slickenside in 3 distinct locations; it's definitely not secondary fusion crust. Looking forward to hearing more on the subject. Michael in so. Cal. On Tue, May 21, 2013 at 7:29 AM, Jim Wooddell jimwoodd...@gmail.com wrote: Hi Bob and all! I might be wrong in assuming, but your slickensides sounds like you are attempting to describe secondary fusion??? We have lots of evidence in various meteorites where they broke apart for whatever reason at the weak boundaries. For example, Franconia area meteorites (some) break apart from both sides of a metal vein leaving three pieces...two chondrite fragments and an H-Metal cornflake. It's sort of like looking at a bad weld through xray. How can you tell? Look at more and look closer. A 3D CT sort of scan that has become popular with Sutter's Mill or Dr. Agee's research on Black Beauty may reveal what you speak of. Just my thoughts. Kind Regards, Jim On Tue, May 21, 2013 at 7:06 AM, Bob King nightsk...@gmail.com wrote: Hi everyone, Many pieces of broken Chelyabinsk specimens display what appears like fusion crust over slickensides, but is that what it really is? I've talked with Blaine Reed and he thinks we're seeing blackish shock veins (planes really) where the meteorite split along a line of weakness. He even mentioned a piece he's seen where a large shock vein in the matrix leads directly to the broken, dark face. Assuming Chelyabinsk shows both slickensides and shock vein planes, how do you tell them apart? Thanks for your thoughts. Bob __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list -- Jim Wooddell jimwoodd...@gmail.com 928-247-2675 __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit
Re: [meteorite-list] Chelyabinsk - slickensides or shock planes?
Hi Bernd! Doesn't sound like that discussion came to any conclusion. I think there was one in 2003 too! I think this discussion has been going on since prior to 1966, ref the abstract link I posted. I do see striations and typically the slickensides I am familiar with are typically larger, not tiny parts of very small rocks. Hundreds of pictures of it on the web. I'd really like to see a scientific explanation for them in meteorites as very small parts of small rocks as they are being defined. Sort of looking around for an explanation and haven't found anything at this time. The ones in Anne's pictures, for example, are not part of an individual clast that could have been a bigger rock that had slickensides and you can clearly see breccias suggesting that feature happened after things came together. I think I also see a contiguous border, not strings that are continuous which, to me, would indicate it part of something bigger. Then how to explain a weak boundary that just happens to contain slickensides considering how these boundaries were formed in the first place! I love it! Jim On 5/21/2013 2:36 PM, Bernd V. Pauli wrote: Hello All, We had a similar discussion many, many years ago (September 2001). Here's a short overview of our results: Summary: - broken surface is covered with glossy striations - slickensides are identified by shiny mirror like surfaces on an otherwise rough rock - they are the product of faulting in a rock body (as the crust shifts, even slightly, the roughness of the rock tends to smooth) - slickensides are formed from the movement of rocks relative to each other along fracture planes in fault zones - rub your finger along the grooves which make up the slickensides: * they feel rough when you move your finger in the direction opposite to which the adjacent rock moved to form the slickensides + they feel smooth when you rub in the same direction the adjacent rock moved because it sheared off any microscopic projections or rough edges as it moved = Not found in shatter cones! - slickensides are formed when opposite sides of rock faults move in different directions - extreme pressure generates frictional heat as the rock faces are forced past each other partially melting a thin veneer of rock at the interface (result: smoothing of rough edges and a polished looking surface) - they are not formed by explosive breakup in the earth's atmosphere (in such a breakup pieces would be flying apart from each other whereas in slickensides the opposite is happening: the rock faces are being forced against each other) but: see below ** - possible formation scenario: an impact event in space results in movement of two adjacent parts of the stony meteorite relative to each other along a preexisting fracture plane thus creating grooves - slickensides are polished, grooved surfaces that occur along shear planes - slickensides form along internal shear planes as opposite parts move past one another - opposite parts rub against each other, their surfaces become smoothed, lineated, and grooved - slickensides are formed when two planar sides grind past each other - slickensides can be created at the moment of breakup (not by the explosive part of this breakup but rather when two parts of the meteorite grind past each other along a pre- existing fracture – so-called shear rupturing) ** and here are some of the listees that participated in the discussion: Charlie Devine (started the discussion), Eric Olson, Robert Verish, ... to name a few. Cheers, Bernd __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list - No virus found in this message. Checked by AVG - www.avg.com Version: 2013.0.3343 / Virus Database: 3162/6344 - Release Date: 05/21/13 __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chelyabinsk - slickensides or shock planes?
Thank you, Anne, I was pretty sure I was correct in my opinion on this, but verification by other esteemed list members NEVER hurts! Copying my photo?... no harm, no foul. Taking liberties sometimes is a good thing. :-) Thanks again - Mal On 5/21/2013 6:10 PM, Anne Black wrote: Yes, Mal, I believe that what you are looking at on this picture is a fracture along a shock vein, it is patchy, it is not as shiny and it is not fibrous looking like a slickenside. I took the liberty of copying your picture and putting side by side with mine, I hope you don't mind. Look at the difference. Anne M. Black www.IMPACTIKA.com impact...@aol.com -Original Message- From: Malvin Bishop Jr magbi...@lowcountry.com To: meteorite-list meteorite-list@meteoritecentral.com Sent: Tue, May 21, 2013 3:51 pm Subject: Re: [meteorite-list] Chelyabinsk - slickensides or shock planes? This is what I was referring to in my previous email regarding one of my Chelyabinsk specimens showing a feature where it appears to be fractured along a weakened shock vein/point where melt had filled the vein before the actual splitting apart. The melt is very evident. Am I thinking correctly on this Mike, Sean, or whomever wishes to respond? http://s1300.photobucket.com/user/N68830/media/Chelyabinsk_fragment_zps1a7dfce6.jpg.html Mal On 5/21/2013 11:48 AM, Bob King wrote: Hi Sean, That photo shows it exactly! Thanks, Bob On Tue, May 21, 2013 at 10:24 AM, Sean T. Murray s...@bellsouth.net wrote: I've noticed the same thing... I think this is a laterally exposed shock vein... sometimes they are crusted over, other times they are pretty fresh, so you can see the size of the exposed plane... http://www.fallingrocks.com/Collections/Chelyabinsk.htm (4th picture down, top left of photo...) It's hard to take a picture of because it is so reflective, but it it quite a beautiful feature of this fall. Sean. -Original Message- From: Sergey Vasiliev Sent: Tuesday, May 21, 2013 11:16 AM To: Michael Mulgrew Cc: meteorite list Subject: Re: [meteorite-list] Chelyabinsk - slickensides or shock planes? Hi All, Look at the two pictures of the same stone. This is a fresh broken side with black shock veins on a very light matrix: - http://sv-meteorites.com/gallery/chelybinsk/02.jpg And this side is secondary crust over the shock vein: - http://sv-meteorites.com/gallery/chelybinsk/01.jpg You can find a lot of interesting things in Chelyabinsk ;-) All the best, Sergey On Tue, May 21, 2013 at 4:59 PM, Michael Mulgrew mikest...@gmail.com wrote: Bob, My piece is just over 5g, but it was broken off a slightly larger piece, probably less than 50g before it broke. Michael in so. Cal. On Tue, May 21, 2013 at 7:48 AM, Bob King nightsk...@gmail.com wrote: Michael and all, I forgot to add that even small 2-3g Chelyabinsks show this same slick, grey material coating their broken faces. Can slickensides form on rocks this small? Bob On Tue, May 21, 2013 at 9:43 AM, Michael Mulgrew mikest...@gmail.com wrote: Bob, Jim, List, I have a small piece that displays the slickenside in 3 distinct locations; it's definitely not secondary fusion crust. Looking forward to hearing more on the subject. Michael in so. Cal. On Tue, May 21, 2013 at 7:29 AM, Jim Wooddell jimwoodd...@gmail.com wrote: Hi Bob and all! I might be wrong in assuming, but your slickensides sounds like you are attempting to describe secondary fusion??? We have lots of evidence in various meteorites where they broke apart for whatever reason at the weak boundaries. For example, Franconia area meteorites (some) break apart from both sides of a metal vein leaving three pieces...two chondrite fragments and an H-Metal cornflake. It's sort of like looking at a bad weld through xray. How can you tell? Look at more and look closer. A 3D CT sort of scan that has become popular with Sutter's Mill or Dr. Agee's research on Black Beauty may reveal what you speak of. Just my thoughts. Kind Regards, Jim On Tue, May 21, 2013 at 7:06 AM, Bob King nightsk...@gmail.com wrote: Hi everyone, Many pieces of broken Chelyabinsk specimens display what appears like fusion crust over slickensides, but is that what it really is? I've talked with Blaine Reed and he thinks we're seeing blackish shock veins (planes really) where the meteorite split along a line of weakness. He even mentioned a piece he's seen where a large shock vein in the matrix leads directly to the broken, dark face. Assuming Chelyabinsk shows both slickensides and shock vein planes, how do you tell them apart? Thanks for your thoughts. Bob __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list -- Jim Wooddell jimwoodd...@gmail.com 928-247-2675
Re: [meteorite-list] Chelyabinsk - slickensides or shock planes?
Bernd, perfect summary. Thanks. - Original Message - From: Bernd V. Pauli bernd.pa...@paulinet.de To: meteorite-list@meteoritecentral.com Sent: Tuesday, May 21, 2013 2:36 PM Subject: [meteorite-list] Chelyabinsk - slickensides or shock planes? Hello All, We had a similar discussion many, many years ago (September 2001). Here's a short overview of our results: Summary: - broken surface is covered with glossy striations - slickensides are identified by shiny mirror like surfaces on an otherwise rough rock - they are the product of faulting in a rock body (as the crust shifts, even slightly, the roughness of the rock tends to smooth) - slickensides are formed from the movement of rocks relative to each other along fracture planes in fault zones - rub your finger along the grooves which make up the slickensides: * they feel rough when you move your finger in the direction opposite to which the adjacent rock moved to form the slickensides + they feel smooth when you rub in the same direction the adjacent rock moved because it sheared off any microscopic projections or rough edges as it moved = Not found in shatter cones! - slickensides are formed when opposite sides of rock faults move in different directions - extreme pressure generates frictional heat as the rock faces are forced past each other partially melting a thin veneer of rock at the interface (result: smoothing of rough edges and a polished looking surface) - they are not formed by explosive breakup in the earth's atmosphere (in such a breakup pieces would be flying apart from each other whereas in slickensides the opposite is happening: the rock faces are being forced against each other) but: see below ** - possible formation scenario: an impact event in space results in movement of two adjacent parts of the stony meteorite relative to each other along a preexisting fracture plane thus creating grooves - slickensides are polished, grooved surfaces that occur along shear planes - slickensides form along internal shear planes as opposite parts move past one another - opposite parts rub against each other, their surfaces become smoothed, lineated, and grooved - slickensides are formed when two planar sides grind past each other - slickensides can be created at the moment of breakup (not by the explosive part of this breakup but rather when two parts of the meteorite grind past each other along a pre- existing fracture - so-called shear rupturing) ** and here are some of the listees that participated in the discussion: Charlie Devine (started the discussion), Eric Olson, Robert Verish, ... to name a few. Cheers, Bernd __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chelyabinsk - slickensides or shock planes?
Thank you, Bernd. You are a river to your fellow enthusiasts. Guido -Original Message- From: Richard Montgomery rickm...@earthlink.net Sent: May 21, 2013 5:21 PM To: Bernd V. Pauli bernd.pa...@paulinet.de, meteorite-list@meteoritecentral.com Subject: Re: [meteorite-list] Chelyabinsk - slickensides or shock planes? Bernd, perfect summary. Thanks. - Original Message - From: Bernd V. Pauli bernd.pa...@paulinet.de To: meteorite-list@meteoritecentral.com Sent: Tuesday, May 21, 2013 2:36 PM Subject: [meteorite-list] Chelyabinsk - slickensides or shock planes? Hello All, We had a similar discussion many, many years ago (September 2001). Here's a short overview of our results: Summary: - broken surface is covered with glossy striations - slickensides are identified by shiny mirror like surfaces on an otherwise rough rock - they are the product of faulting in a rock body (as the crust shifts, even slightly, the roughness of the rock tends to smooth) - slickensides are formed from the movement of rocks relative to each other along fracture planes in fault zones - rub your finger along the grooves which make up the slickensides: * they feel rough when you move your finger in the direction opposite to which the adjacent rock moved to form the slickensides + they feel smooth when you rub in the same direction the adjacent rock moved because it sheared off any microscopic projections or rough edges as it moved = Not found in shatter cones! - slickensides are formed when opposite sides of rock faults move in different directions - extreme pressure generates frictional heat as the rock faces are forced past each other partially melting a thin veneer of rock at the interface (result: smoothing of rough edges and a polished looking surface) - they are not formed by explosive breakup in the earth's atmosphere (in such a breakup pieces would be flying apart from each other whereas in slickensides the opposite is happening: the rock faces are being forced against each other) but: see below ** - possible formation scenario: an impact event in space results in movement of two adjacent parts of the stony meteorite relative to each other along a preexisting fracture plane thus creating grooves - slickensides are polished, grooved surfaces that occur along shear planes - slickensides form along internal shear planes as opposite parts move past one another - opposite parts rub against each other, their surfaces become smoothed, lineated, and grooved - slickensides are formed when two planar sides grind past each other - slickensides can be created at the moment of breakup (not by the explosive part of this breakup but rather when two parts of the meteorite grind past each other along a pre- existing fracture - so-called shear rupturing) ** and here are some of the listees that participated in the discussion: Charlie Devine (started the discussion), Eric Olson, Robert Verish, ... to name a few. Cheers, Bernd __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
