Kevin Righter, NASA-JSC
This newsletter reports 365 new meteorites from the 2010 and 2011 ANSMET seasons from the Miller Range (MIL11), Dominion Range (DOM10), La Paz Ice Field (LAP10), Patuxent Range (PAT10), Buckley Island (BUC10), and Allan Hills (ALH10) regions. Detailed descriptions are provided for one each of CV and CR chondrites, several shock blackened L chondrites, an L3.8 chondrite, an EL6 chondrite, and 9 HED meteorites.
Calcium sulfate found in lunar meteorite PCA 02007
In the process of sampling lunar meteorite PCA 02007 in Spring of 2012, an unusual light greenish-blue crystal was discovered upon breaking open a fresh surface of the sample. In order to identify this mineral, we obtained a Raman spectrum (non-destructive to the sample), and found that it is a calcium sulfate either anhydrite or gypsum. This unexpected finding might be of potential interest to the community so we are announcing it here. Any interested researchers can make a request for this sample in the upcoming Spring 2013 MWG meeting (request deadline is March 8th).
Unusual greenish-blue calcium sulfate crystal found in meteorite PCA 02007
Raman spectra of PCA 02007 crystal compared to anhydrite from Moundhouse, Nevada (USA)
Meteorite reclassifications / corrections
MIL 11207 revised description (announced vol. 35, no. 2):
The section is comprised of coarse grained (100-200 micron), equigranular olivine, sometimes poikilitically enclosed in mm-sized feldspar with sulfides, oxides and hornblende (yes, hornblende). Olivine compositions are Fa40, feldspar is An10Or4. The meteorite is an R6 chondrite with pronounced shock effects. It is petrologically distinct from the LAP 04840 pairing group, although it shares the common feature of being a hydrous phase bearing R chondrite.
MIL 090982 reclassification (announced vol. 35, no. 1): This sample was originally announced as an LL6 chondrite (without a detailed description), but re-examination has revealed it is a CK6 chondrite. A new description is presented in the section with other new petrographic descriptions.
QUE 99038 reclassification (announced vol. 24, no. 1): This sample was originally classified as a CM2 chondrite. However, A. Rubin (UCLA) brought to our attention several important observations suggesting this classification is incorrect. Inspection of the JSC library section (,9) reveals many large and igneous rimmed chondrules, many CAI and other inclusions, and only a small amount of matrix. The high % matrix and small chondrules typical of a CM2 chondrite are absent. We therefore re-classify this sample as a CV3 chondrite.
LAP 03834 reclassification (announced vol. 29, no. 1): This sample was originally classified as a CK3 chondrite, but chemical analyses reveal that it (as well as MET 01149 which we reclassified a few years ago) is very close in composition (Zn/Mn vs. Al/Mn) to many other R chondrites (Isa, M. et al., 2011, LPSC abstract #1876). This information, together with the observation that there is abundant sulfide, but little to no magnetite has led us to reclassify this sample as an R3 chondrite.
MAC 02453 reclassification (announced vol. 28, no. 1): This sample was originally classified as a CK5 chondrite, but chemical analyses reveal that it is very close in composition (Zn/Mn vs. Al/Mn) to many other LL chondrites (Isa, M. et al., 2011, LPSC abstract #1876). This information, together with the observation that there is metal present and no magnetite, has led us to reclassify this sample as an LL5 chondrite.
LAP 03923 reclassification (announced vol. 29, no. 1): This sample was originally classified as a CK5 chondrite, but chemical analyses reveal that it is very close in composition (Zn/Mn vs. Al/Mn) to many other LL chondrites (Isa, M. et al., 2011, LPSC abstract #1876). This information, together with the observation that there is metal present and no magnetite, has led us to reclassify this sample as an LL5 chondrite.
New book will highlight US Antarctic meteorite collection
The US Antarctic meteorite collection has been growing steadily since the mid-70s when the program got started. Despite the prominent role the collection has played in the field of meteoritics and defining new meteorite groups, there has never been a comprehensive summary of the collection that focuses on its various components such as field collecting, classification, curation, and influential individual samples. Therefore, last year we organized a book project through the American Geophysical Union (AGU) Press that will include reviews of the history, field collection, classification, curation, specific meteorite groups (martian, lunar, achondrites, primitive chondrites, ungrouped meteorites), exposure ages, and collection statistics. The chapters are being reviewed currently, with revisions due in the Spring, and book appearing in the Summer or Fall. We hope this book will provide an overarching summary of the more important aspects of the collection, and be a valuable resource for the community.
2012-2013 ANSMET Field Season Report
Ralph Harvey, Principal Investigator, ANSMET
I get asked for my opinion regarding the differences between Science and Engineering (with capital S and E respectively) a lot. This is probably because like engineering, ANSMET is a hybrid of science and service with a heavy dependence on technology. One of the differences that fascinates me is how we define “success”. For a scientist, a non-result (or a negative result) that throws out your hypothesis can easily be as valuable and important as results that confirming your theories. For an engineer designing a new solar panel, or robot, or (god forbid) a bridge, failure often just isn't an option. As a result, the two kinds of research tend to define success in very different ways.
Recon Team: Katie Joy, Tomoko Arai, John Schutt, Joe Boyce
Which leads me to the recently completed ANSMET field season of 2012-2013, where we definitely had success but not quite what the pre-season plans would have suggested. Two parties went into the field as planned and on schedule; a 4-person reconnaissance party sent to explore some promising sites in the most southerly reaches of the Transantarctic Mountains, and an 8-person systematic searching team sent to the Larkman Nunataks and the ice fields adjacent to Mts Cecily, Emily and Raymond in the Grosvenor Mountains. The recon team recovered meteorite from several sites near the Klein Glacier landing site and the Graves Nunatak region; but as they moved to sites along the upper Robison Glacier, the weather stopped cooperating. At one stage they endured the longest weather-related work-stoppage in ANSMET’s 37 year history, a full 14 days. It wasn’t all about snow and wind, either; warmer than usual weather in the McMurdo Sound region meant the Pegasus runway was too soft for use by wheeled aircraft, meaning the US Antarctic Program’s ski–equipped aircraft (LC–130’s and Twin Otters) had to do double duty, bringing cargo from the civilized world as well as supporting activities in the field and at remote stations. Together these factors led to a recon season where we managed to visit less than half of the sites we had hoped for, and the total number of meteorite recoveries were correspondingly low— around 3 dozen.
John, Joe, Tomoko, Katie (after 14 straight tent days)
The systematic team had much better luck with the weather, and after a few days of acclimatization at the Mt. Bumstead ice fields, the team arrived and set up camp at Larkman Nunatak. The ice fields in this area are relatively small; but there’s a challenge hiding at the foot of Larkman Nunatak, a moraine brimming with meteorites. Previous visits to the site emphasized the desire not only to complete searching of the ice but also to finish a highly-controlled methodical foot search in that moraine. Neanderthals that we are, we even went so far as to try a few new things, like smaller wire–supported flags and battery powered drills for marking paths and finds, and the use of a metal detector for double–checking. The payoff appears to have been substantial; about 365 specimens, including many that appear “unusual” and contrary to expectations, of significant size.
With searching at Larkman completed, the team cleaned up camp and set the course for the Grosvenor ice fields. Just as they set off, however, one of the field party members took ill, and the traverse was quickly cancelled. ANY medical situation in the field has the potential to turn disastrous, so the stricken field party member was quickly evacuated back to McMurdo and eventually to Christchurch, where tests proved (thankfully) that no serious harm resulted. This incident, occurring when it did, pretty much ended the season for the systematic team; but their quick and appropriate actions were roundly applauded within USAP and demonstrated the value of the careful preparations and training ANSMET is known for in the Antarctic Program. The team, dealing with some of the previously mentioned airplane issues, took about another week to get out of the field. The final total for both field teams was just above 400 finds, but may be lower given the likely inclusion of some terrestrial specimens.
The ANSMET Systematic Team
One important programmatical item to note, historically ANSMET has been supported by both NASA and the National Science Foundation. Many of you know NSF will no longer support the program directly after this coming summer. NASA has made it clear they understand the value of continuing ANSMET field work with as few interruptions as possible, so there is very little danger of the program going away. As we transition from multiple funding sources to NASA alone, particularly in the current funding climate, changes in our operations are likely. One possible result of this transition may be that ANSMET, for the first time in over 20 years, misses a field season. Given how many of you rely on a continuous supply of new ANSMET samples for your research, we felt it was important to let you know of this potential interruption.
Report from the Smithsonian
Cari Corrigan, Geologist (Dept. of Mineral Sci.)
This newsletter announces the classification of 365 meteorites from Allan Hills, Buckley Island, Dominion Range, La Paz Ice Field, Miller Range and Patuxent Range. Since the last newsletter, we have completed an inventory of the Antarctic Meteorite Collection at the Museum Support Center and have reorganized storage of the meteorites. This will make it more efficient when processing requests.
The September meeting of the Meteorite Working Group was held at the Smithsonian Institution. Andrew Beck, a post-doc at the Smithsonian, was a member of the 2012 ANSMET team. Andrew had an enjoyable time on the ice finding interesting meteorites for us to classify and for you to study.