[meteorite-list] Meteorite Picture of the Day
Henbury http://www.tucsonmeteorites.com/mpod.asp __ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] The Best Hike on Mars You'll Ever Take
This video compresses 5 years and 4 months of the Martian rover Spirit's travels on the surface of the Red Planet into less than 3 minutes. The Best Hike On Mars You'll Ever Take http://www.npr.org/blogs/krulwich/2011/12/02/143051269/the-best-hike-on-mars-you-ll-ever-take by Robert Krulwich It took five years, three months and 27 days, but you can do it all in three minutes. Here, from start to finish, is what the NASA rover Spirit sniffed, bopped, scratched and saw as it moved across 4.8 miles of the Martian surface. The lens is wide-angled, so the horizon always looks like a curved mountain top; every so often a one-armed probe, looking weirdly lobster-like, will suddenly appear, noodle around, poke, tap or sift through the Martian soil. Towards the end you'll catch glimpses of the sun setting, (same sun! different set! I thought.) until Spirit gets stuck in the Martian muck and then, dramatically, everything goes dark. The folks who edited this together added movie music, which makes it really fun to watch. This is the best low-res, low-priced, low energy Martian hike you'll ever take. - Phil Whitmer Joshua Tree Earth Space Museum __ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Meteorite Picture of the Day
Nice piece. I wonder what one of those irons would look like cleaned of the desert varnish. Mike in CO On Dec 5, 2011, at 4:00 AM, valpar...@aol.com valpar...@aol.com wrote: Henbury http://www.tucsonmeteorites.com/mpod.asp __ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] Primitive Achondrite Question
Hi all, I just bought a smallish collection and several of the slices that came with are NWA 3100. Mike Farmer's card was included and lists NWA 3100 as an LL7. The Met-Bul calls NWA 3100 a Primitive achondrite - not an LL7. My question is this, Does LL7 denote a particular Primitive achondrite? If so which one? If not then what type is this? BTW - I think Ted Bunch did the classification -- Rock On! Ruben Garcia Website: http://www.mr-meteorite.net Articles: http://www.meteorite.com/blog/ Videos: http://www.youtube.com/profile?user=meteorfright#p/u __ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] NASA Finds 'Merging Tsunami' Doubled Japan Destruction
Dec. 5, 2011 Steve Cole Headquarters, Washington 202-358-0918 stephen.e.c...@nasa.gov Alan Buis Jet Propulsion Laboratory, Pasadena, Calif. 818-354-0474 alan.b...@jpl.nasa.gov RELEASE: 11-405 NASA FINDS 'MERGING TSUNAMI' DOUBLED JAPAN DESTRUCTION WASHINGTON -- NASA and Ohio State University researchers have discovered the major tsunami generated by the March 2011 Tohoku-Oki quake centered off northeastern Japan was a long-hypothesized merging tsunami. The tsunami doubled in intensity over rugged ocean ridges, amplifying its destructive power at landfall. Data from NASA and European radar satellites captured at least two wave fronts that day. The fronts merged to form a single, double-high wave far out at sea. This wave was capable of traveling long distances without losing power. Ocean ridges and undersea mountain chains pushed the waves together along certain directions from the tsunami's origin. The discovery helps explain how tsunamis can cross ocean basins to cause massive destruction at some locations while leaving others unscathed. The data raise hope that scientists may be able to improve tsunami forecasts. Research scientist Y. Tony Song of NASA's Jet Propulsion Laboratory in Pasadena, Calif., and professor C.K. Shum of The Ohio State University discussed the data and simulations that enabled them to piece the story together at a media briefing Monday, Dec. 5, at the American Geophysical Union meeting in San Francisco. It was a one in 10 million chance that we were able to observe this double wave with satellites, Song said. He is the principal investigator in the NASA-funded study. Researchers have suspected for decades that such 'merging tsunamis' might have been responsible for the 1960 Chilean tsunami that killed about 200 people in Japan and Hawaii, but nobody had definitively observed a merging tsunami until now, Song said. It was like looking for a ghost. A NASA-French Space Agency satellite altimeter happened to be in the right place at the right time to capture the double wave and verify its existence. The NASA-Centre National d'Etudes Spaciales Jason-1 satellite passed over the tsunami on March 11, as did two other satellites -- the NASA-European Jason-2 and the European Space Agency's EnviSAT. All three carry radar altimeters, which measure sea level changes to an accuracy of a few centimeters. Each satellite crossed the tsunami at a different location, measuring the wave fronts as they occurred. Jason-1 launched 10 years ago this week on Dec. 7, 2001. We can use what we learned to make better forecasts of tsunami danger in specific coastal regions anywhere in the world, depending on the location and the mechanism of an undersea quake, Shum said. The researchers think ridges and undersea mountain chains on the ocean floor deflected parts of the initial tsunami wave away from each other to form independent jets shooting off in different directions, each with its own wave front. The sea floor topography nudges tsunami waves in varying directions and can make its destruction appear random. For that reason, hazard maps that try to predict where tsunamis will strike rely on sub-sea topography. Previously, these maps considered only topography near a particular shoreline. This study suggests scientists may be able to create maps that take into account all undersea topography, even sub-sea ridges and mountains far from shore. Song and his team were able to verify the satellite data through model simulations based on independent data, including GPS data from Japan and buoy data from the National Oceanic and Atmospheric Administration's Deep-ocean Assessment and Reporting of Tsunamis program. Tools based on this research could help officials forecast the potential for tsunami jets to merge, Song said. This, in turn, could lead to more accurate coastal tsunami hazard maps to protect communities and critical infrastructure. For more information about presentations at the American Geophysical Union meeting, visit: http://www.nasa.gov/agu -end- __ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] New NASA Dawn Visuals Show Vesta's 'Color Palette'
http://www.jpl.nasa.gov/news/news.cfm?release=2011-375cid=release_2011-375msource=2011375tr=yauid=9960738 New NASA Dawn Visuals Show Vesta's 'Color Palette' Jet Propulsion Laboratory December 5, 2011 Vesta appears in a splendid rainbow-colored palette in new images obtained by NASA's Dawn spacecraft. The colors, assigned by scientists to show different rock or mineral types, reveal Vesta to be a world of many varied, well-separated layers and ingredients. Vesta is unique among asteroids visited by spacecraft to date in having such wide variation, supporting the notion that it is transitional between the terrestrial planets -- like Earth, Mercury, Mars and Venus -- and its asteroid siblings. In images from Dawn's framing camera, the colors reveal differences in the rock composition associated with material ejected by impacts and geologic processes, such as slumping, that have modified the asteroid's surface. Images from the visible and infrared mapping spectrometer reveal that the surface materials contain the iron-bearing mineral pyroxene and are a mixture of rapidly cooled surface rocks and a deeper layer that cooled more slowly. The relative amounts of the different materials mimic the topographic variations derived from stereo camera images, indicating a layered structure that has been excavated by impacts. The rugged surface of Vesta is prone to slumping of debris on steep slopes. Dawn scientists presented the new images at the American Geophysical Union meeting in San Francisco on Monday, Dec. 5. The panelists included Vishnu Reddy, framing camera team associate, Max Planck Institute for Solar System Research, Katlenburg-Lindau, Germany; Eleonora Ammannito, visible and infrared spectrometer team associate, Italian Space Agency, Rome; and David Williams, Dawn participating scientist, Arizona State University, Tucson. Vesta's iron core makes it special and more like terrestrial planets than a garden-variety asteroid,` said Carol Raymond, Dawn's deputy principal investigator at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The distinct compositional variation and layering that we see at Vesta appear to derive from internal melting of the body shortly after formation, which separated Vesta into crust, mantle and core. The presentation also included a new movie, created by David O'Brien of the Planetary Science Institute, Tucson, Ariz., that takes viewers on a spin around a hill on Vesta that appears to be made of a distinctly darker material than the rest of the crust. Dawn launched in September 2007 and arrived at Vesta on July 15, 2011. Following a year at Vesta, the spacecraft will depart in July 2012 for the dwarf planet Ceres, where it will arrive in 2015. Dawn's mission to Vesta and Ceres is managed by JPL for NASA's Science Mission Directorate in Washington. JPL is a division of the California Institute of Technology in Pasadena. Dawn is a project of the directorate's Discovery Program, managed by NASA's Marshall Space Flight Center in Huntsville, Ala. UCLA is responsible for overall Dawn mission science. Orbital Sciences Corp. in Dulles, Va., designed and built the spacecraft. The German Aerospace Center, the Max Planck Institute for Solar System Research, the Italian Space Agency and the Italian National Astrophysical Institute are international partners on the mission team. More information about the Dawn mission is online at: http://www.nasa.gov/dawn and http://dawn.jpl.nasa.gov . To follow the mission on Twitter, visit: http://www.twitter.com/NASA_Dawn . Priscilla Vega 818-354-1357 Jet Propulsion Laboratory, Pasadena, Calif. priscilla.r.v...@jpl.nasa.gov 2011-375 __ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Primitive Achondrite Question
Type 7 is considered by most of those who use it to represent the highest degree of thermal metamorphism that a chondrite can experience without melting. As implied in that first sentence, some petrologists don't distinguish these from type 6. The term primitive achondrite is widely taken to be the next stage: you make them when a chondrite partially melts, and the process of crystal-melt separation begins. The primitive part says that the bulk composition is still fairly close to chondritic. But these definitions are not used by everybody, and you will get arguments about them. Clearly, the LL part of an LL7 classification for NWA 3100 is unlikely. O isotopes are below the terrestrial fractionation line, which basically rules it out. So it is not an LL7. Bunch has shown that the O isotopes are closer to CR chondrites. The hard part is the type 7 vs. primitive achondrite distinction. Bunch et al.'s 2005 and 2008 LPSC abstracts do not report anything in NWA 3100 that I take as evidence of melting or differentiation. So I don't see any reason to call these primitive achondrites, at least not based on these findings. I think the Bunch et al.'s conclusion that NWA 3100 is a CR6 is the best we have right now, but I think you still have to think of this as preliminary. Ted can correct me, but I think it was actually the nomcom that pushed for calling this a PAC, amid controversy on the committee. Jeff On 12/5/2011 8:23 PM, Ruben Garcia wrote: Hi all, I just bought a smallish collection and several of the slices that came with are NWA 3100. Mike Farmer's card was included and lists NWA 3100 as an LL7. The Met-Bul calls NWA 3100 a Primitive achondrite - not an LL7. My question is this, Does LL7 denote a particular Primitive achondrite? If so which one? If not then what type is this? BTW - I think Ted Bunch did the classification __ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Primitive Achondrite Question
There are relict chondrules identifyable in LL7's according to the definition I read, though if you dig through David Weir's or Dr. Bunch's websites you will probably get updated information. So, it can't be an achondrite, primitive or not. If anything it would have to be a highly evolved chondrite; --- same logic we just saw with Al Haggounia 001 not being an aubrite = chondrule .. not an aubrite but in that Al Haggounia case, chondrules that were not completely mineralized with replacements are present, and Greg Hupe has an unambiguous chondrule that he kindly shared with me that is extremely well defined (dropping it to a 3 in that case assuming not 100% relict). What happens when a chondrite is just past the metamorphic stage that chondrules are no longer identifyable is probably a variable process causing confusion among classifications of sparcely occuring chondrules in 6's and those of 7's. Must be a bit to come up with uniform criteria since nature has her own sometimes cryptic ways. It would only get interesting if different parts of the same rock get baked in a non-uniform oven. Kindest wishes Doug -Original Message- From: Ruben Garcia mrmeteor...@gmail.com To: Meteorite List meteorite-list@meteoritecentral.com Sent: Mon, Dec 5, 2011 8:23 pm Subject: [meteorite-list] Primitive Achondrite Question Hi all, I just bought a smallish collection and several of the slices that came with are NWA 3100. Mike Farmer's card was included and lists NWA 3100 as an LL7. The Met-Bul calls NWA 3100 a Primitive achondrite - not an LL7. My question is this, Does LL7 denote a particular Primitive achondrite? If so which one? If not then what type is this? BTW - I think Ted Bunch did the classification -- Rock On! Ruben Garcia Website: http://www.mr-meteorite.net Articles: http://www.meteorite.com/blog/ Videos: http://www.youtube.com/profile?user=meteorfright#p/u __ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Primitive Achondrite Question
Well stated Jeff and I agree! Thank you. There is the thing about metachondrite terminology, but we shall leave this dead horse alone for the time being. Two of these unremitting classification issues in 3 days is much too much for me in one week, especially when my butt is tied to both of them. Ted On 12/5/11 7:02 PM, Jeff Grossman jngross...@gmail.com wrote: Type 7 is considered by most of those who use it to represent the highest degree of thermal metamorphism that a chondrite can experience without melting. As implied in that first sentence, some petrologists don't distinguish these from type 6. The term primitive achondrite is widely taken to be the next stage: you make them when a chondrite partially melts, and the process of crystal-melt separation begins. The primitive part says that the bulk composition is still fairly close to chondritic. But these definitions are not used by everybody, and you will get arguments about them. Clearly, the LL part of an LL7 classification for NWA 3100 is unlikely. O isotopes are below the terrestrial fractionation line, which basically rules it out. So it is not an LL7. Bunch has shown that the O isotopes are closer to CR chondrites. The hard part is the type 7 vs. primitive achondrite distinction. Bunch et al.'s 2005 and 2008 LPSC abstracts do not report anything in NWA 3100 that I take as evidence of melting or differentiation. So I don't see any reason to call these primitive achondrites, at least not based on these findings. I think the Bunch et al.'s conclusion that NWA 3100 is a CR6 is the best we have right now, but I think you still have to think of this as preliminary. Ted can correct me, but I think it was actually the nomcom that pushed for calling this a PAC, amid controversy on the committee. Jeff On 12/5/2011 8:23 PM, Ruben Garcia wrote: Hi all, I just bought a smallish collection and several of the slices that came with are NWA 3100. Mike Farmer's card was included and lists NWA 3100 as an LL7. The Met-Bul calls NWA 3100 a Primitive achondrite - not an LL7. My question is this, Does LL7 denote a particular Primitive achondrite? If so which one? If not then what type is this? BTW - I think Ted Bunch did the classification __ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Primitive Achondrite Question
Thank you Jeff, Believe it or not, you enlightened my small small knowledge about this. Further sales of metachondrite terminology is hereby suspended until Ted's posterier heals. Sorry, just had to, John. - Original Message - From: Ted Bunch tbe...@cableone.net To: Jeff Grossman jngross...@gmail.com; meteorite-list@meteoritecentral.com Sent: Monday, December 05, 2011 10:00 PM Subject: Re: [meteorite-list] Primitive Achondrite Question Well stated Jeff and I agree! Thank you. There is the thing about metachondrite terminology, but we shall leave this dead horse alone for the time being. Two of these unremitting classification issues in 3 days is much too much for me in one week, especially when my butt is tied to both of them. Ted On 12/5/11 7:02 PM, Jeff Grossman jngross...@gmail.com wrote: Type 7 is considered by most of those who use it to represent the highest degree of thermal metamorphism that a chondrite can experience without melting. As implied in that first sentence, some petrologists don't distinguish these from type 6. The term primitive achondrite is widely taken to be the next stage: you make them when a chondrite partially melts, and the process of crystal-melt separation begins. The primitive part says that the bulk composition is still fairly close to chondritic. But these definitions are not used by everybody, and you will get arguments about them. Clearly, the LL part of an LL7 classification for NWA 3100 is unlikely. O isotopes are below the terrestrial fractionation line, which basically rules it out. So it is not an LL7. Bunch has shown that the O isotopes are closer to CR chondrites. The hard part is the type 7 vs. primitive achondrite distinction. Bunch et al.'s 2005 and 2008 LPSC abstracts do not report anything in NWA 3100 that I take as evidence of melting or differentiation. So I don't see any reason to call these primitive achondrites, at least not based on these findings. I think the Bunch et al.'s conclusion that NWA 3100 is a CR6 is the best we have right now, but I think you still have to think of this as preliminary. Ted can correct me, but I think it was actually the nomcom that pushed for calling this a PAC, amid controversy on the committee. Jeff On 12/5/2011 8:23 PM, Ruben Garcia wrote: Hi all, I just bought a smallish collection and several of the slices that came with are NWA 3100. Mike Farmer's card was included and lists NWA 3100 as an LL7. The Met-Bul calls NWA 3100 a Primitive achondrite - not an LL7. My question is this, Does LL7 denote a particular Primitive achondrite? If so which one? If not then what type is this? BTW - I think Ted Bunch did the classification __ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Primitive Achondrite Question
Hi all, Thanks Jeff and Doug. Sorry Ted, I've been out of town and haven't followed any other similar conversation so I wasn't aware it was a touchy subject. However, since we're here... I still have one last question - actually I need advice on what to call these slices when I advertise them for sale. Jeff says (and Ted seems to agree) I think the Bunch et al.'s conclusion that NWA 3100 is a CR6 is the best we have right now, but I think you still have to think of this as preliminary. I bought this collection to sell so Can I call it a CR6 when I sell it or should I call it a primitive achondrite? On Mon, Dec 5, 2011 at 8:45 PM, John Lutzon j...@hc.fdn.com wrote: Thank you Jeff, Believe it or not, you enlightened my small small knowledge about this. Further sales of metachondrite terminology is hereby suspended until Ted's posterier heals. Sorry, just had to, John. - Original Message - From: Ted Bunch tbe...@cableone.net To: Jeff Grossman jngross...@gmail.com; meteorite-list@meteoritecentral.com Sent: Monday, December 05, 2011 10:00 PM Subject: Re: [meteorite-list] Primitive Achondrite Question Well stated Jeff and I agree! Thank you. There is the thing about metachondrite terminology, but we shall leave this dead horse alone for the time being. Two of these unremitting classification issues in 3 days is much too much for me in one week, especially when my butt is tied to both of them. Ted On 12/5/11 7:02 PM, Jeff Grossman jngross...@gmail.com wrote: Type 7 is considered by most of those who use it to represent the highest degree of thermal metamorphism that a chondrite can experience without melting. As implied in that first sentence, some petrologists don't distinguish these from type 6. The term primitive achondrite is widely taken to be the next stage: you make them when a chondrite partially melts, and the process of crystal-melt separation begins. The primitive part says that the bulk composition is still fairly close to chondritic. But these definitions are not used by everybody, and you will get arguments about them. Clearly, the LL part of an LL7 classification for NWA 3100 is unlikely. O isotopes are below the terrestrial fractionation line, which basically rules it out. So it is not an LL7. Bunch has shown that the O isotopes are closer to CR chondrites. The hard part is the type 7 vs. primitive achondrite distinction. Bunch et al.'s 2005 and 2008 LPSC abstracts do not report anything in NWA 3100 that I take as evidence of melting or differentiation. So I don't see any reason to call these primitive achondrites, at least not based on these findings. I think the Bunch et al.'s conclusion that NWA 3100 is a CR6 is the best we have right now, but I think you still have to think of this as preliminary. Ted can correct me, but I think it was actually the nomcom that pushed for calling this a PAC, amid controversy on the committee. Jeff On 12/5/2011 8:23 PM, Ruben Garcia wrote: Hi all, I just bought a smallish collection and several of the slices that came with are NWA 3100. Mike Farmer's card was included and lists NWA 3100 as an LL7. The Met-Bul calls NWA 3100 a Primitive achondrite - not an LL7. My question is this, Does LL7 denote a particular Primitive achondrite? If so which one? If not then what type is this? BTW - I think Ted Bunch did the classification __ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list -- Rock On! Ruben Garcia Website: http://www.mr-meteorite.net Articles: http://www.meteorite.com/blog/ Videos: http://www.youtube.com/profile?user=meteorfright#p/u __ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Primitive Achondrite Question
Hi Ruben, Both of the researchers, based on Dr. Bunch's work seem too agree it is a chondrite. So if I were representing it based on the work cited, I'd say: The definitive classification is still pending, as the initial LL classification has been shown not to be the case, but instead it is thought to be highly evolved chondrite, possibly related to a deeper excavation from the carbonaceous CR parent body. You could fit in likely type 6 if you wanted. I guess that's why nomenclature is such a fun issue. Once we can put a nickname on it, suddenly it is compartmentalized into its own flock of sheep and we all speak of it as if we knew what we were talking about, but easily can miss out on subtile differences that could be much more remarkable. Reminds me of the story in the Little Prince when no one took seriously the Turkish astronomer who discovered the asteroid until he put a suit on himself and gave it a name B612 and everyone suddenly understood everything ;-) Kindest wishes Doug -Original Message- From: Ruben Garcia mrmeteor...@gmail.com To: John Lutzon j...@hc.fdn.com Cc: meteorite-list meteorite-list@meteoritecentral.com; jngrossman jngross...@gmail.com Sent: Mon, Dec 5, 2011 11:02 pm Subject: Re: [meteorite-list] Primitive Achondrite Question Hi all, Thanks Jeff and Doug. Sorry Ted, I've been out of town and haven't followed any other similar conversation so I wasn't aware it was a touchy subject. However, since we're here... I still have one last question - actually I need advice on what to call these slices when I advertise them for sale. Jeff says (and Ted seems to agree) I think the Bunch et al.'s conclusion that NWA 3100 is a CR6 is the best we have right now, but I think you still have to think of this as preliminary. I bought this collection to sell so Can I call it a CR6 when I sell it or should I call it a primitive achondrite? On Mon, Dec 5, 2011 at 8:45 PM, John Lutzon j...@hc.fdn.com wrote: Thank you Jeff, Believe it or not, you enlightened my small small knowledge about this. Further sales of metachondrite terminology is hereby suspended until Ted's posterier heals. Sorry, just had to, John. - Original Message - From: Ted Bunch tbe...@cableone.net To: Jeff Grossman jngross...@gmail.com; meteorite-list@meteoritecentral.com Sent: Monday, December 05, 2011 10:00 PM Subject: Re: [meteorite-list] Primitive Achondrite Question Well stated Jeff and I agree! Thank you. There is the thing about metachondrite terminology, but we shall leave this dead horse alone for the time being. Two of these unremitting classification issues in 3 days is much too much for me in one week, especially when my butt is tied to both of them. Ted On 12/5/11 7:02 PM, Jeff Grossman jngross...@gmail.com wrote: Type 7 is considered by most of those who use it to represent the highest degree of thermal metamorphism that a chondrite can experience without melting. As implied in that first sentence, some petrologists don't distinguish these from type 6. The term primitive achondrite is widely taken to be the next stage: you make them when a chondrite partially melts, and the process of crystal-melt separation begins. The primitive part says that the bulk composition is still fairly close to chondritic. But these definitions are not used by everybody, and you will get arguments about them. Clearly, the LL part of an LL7 classification for NWA 3100 is unlikely. O isotopes are below the terrestrial fractionation line, which basically rules it out. So it is not an LL7. Bunch has shown that the O isotopes are closer to CR chondrites. The hard part is the type 7 vs. primitive achondrite distinction. Bunch et al.'s 2005 and 2008 LPSC abstracts do not report anything in NWA 3100 that I take as evidence of melting or differentiation. So I don't see any reason to call these primitive achondrites, at least not based on these findings. I think the Bunch et al.'s conclusion that NWA 3100 is a CR6 is the best we have right now, but I think you still have to think of this as preliminary. Ted can correct me, but I think it was actually the nomcom that pushed for calling this a PAC, amid controversy on the committee. Jeff On 12/5/2011 8:23 PM, Ruben Garcia wrote: Hi all, I just bought a smallish collection and several of the slices that came with are NWA 3100. Mike Farmer's card was included and lists NWA 3100 as an LL7. The Met-Bul calls NWA 3100 a Primitive achondrite - not an LL7. My question is this, Does LL7 denote a particular Primitive achondrite? If so which one? If not then what type is this? BTW - I think Ted Bunch did the classification __ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com
Re: [meteorite-list] Meteorite Picture of the Day
I wonder what one of those irons would look like cleaned of the desert varnish. Naked, violated, and devoid of character. But that's just my opinion. ;^) To each his own... Linton Nice piece, indeed! - Original Message - From: The Murrays mikebevmur...@gmail.com To: valparint@aol.comvalpar...@aol.com Cc: meteorite-list@meteoritecentral.com Sent: Monday, December 05, 2011 3:22 PM Subject: Re: [meteorite-list] Meteorite Picture of the Day Nice piece. I wonder what one of those irons would look like cleaned of the desert varnish. Mike in CO On Dec 5, 2011, at 4:00 AM, valpar...@aol.com valpar...@aol.com wrote: Henbury http://www.tucsonmeteorites.com/mpod.asp __ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html 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: 2012.0.1873 / Virus Database: 2102/4658 - Release Date: 12/05/11 __ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
