Newsletter Newsletter Newsletter Newsletter Newsletter Volume 26, Number 1 February 2003 Inside this Issue Inside this Issue Inside this Issue Inside this Issue Inside this Issue New Antarctic Meteorite Curator ...... 1 New Meteorites ................................. 2 Mars Meteorite Compendium...............2 New Thin Section Procedures..............2 Report on 2002-03 Field Season...........2 New Meteorites......................................4 Location Abbreviations and Map ..... 4 Table 1: Alpha List of New Meteorites ..................................... 5 Table 2: Newly Classified Specimens ................................... . 14 Notes to Tables 1 & 2 ....................... 15 Table 3: Tentative Pairings .............. 16 Petrographic Descriptions ............... 17 Sample Request Guidelines .............. 24 Antarctic Meteorite Laboratory Contacts ....................................... 24 Meteorites On-Line .......................... 25 Antarctic Meteorite New Antarctic Meteorite Curator Kevin Righter In November, I assumed the position of Antarctic Meteorite Curator at NASA’s Johnson Space Center. I feel very fortunate to have the opportunity to oversee the curation of the Antarctic Meteorite Collection. This is a large and dynamic collection, augmented every year with new, interesting and unique specimens. The meteorite processing team here at JSC does an outstanding job of carrying this out, and we plan to continue with the many new samples returned from the most recent season (see ANSMET report). I welcome any questions, comments or concerns from members of the community – please don’t hesitate to contact me at the address at the end of the newsletter. My interest in meteorites and planetary science was sparked by a summer internship at the Lunar and Planetary Institute in 1987 just after completing college. I studied pallasite meteorites and their possible relation to the eucrite parent body (or Vesta) for a master’s thesis at the University of Michigan with Richard Arculus. Because I had an interest in fieldwork and terrestrial petrology, I pursued a doctoral thesis at the University of California at Berkeley and worked with Ian Carmichael on field and experimental studies of the western Mexican Volcanic Belt. Since 1994, I have been a postdoctoral research associate with Mike Drake at the Lunar and Planetary Laboratory of the University of Arizona. My research there has included experimental studies of metal-silicate equilibrium and core formation and planetary differentiation as well as studies of a broad range of meteorites such as metal-rich chondrites, HED and martian meteorites. I also continue working on problems in basaltic volcanism in continental and island arcs. I was fortunate enough to have the opportunity to be a part of the 99-00 ANSMET field team. The 99-00 field season returned a whopping 1042 samples from the Queen Alexandra Range (Foggy Bottom and Goodwin Nunatak), Lewis Cliffs, Miller Range and Geologists Range. The 1999-2000 ANSMET field team near Goodwin Nunatak, from left to right: John Schutt, Peter Pesch, Phil Bland, Henning Haack, Andreas Weigel, and Kevin Righter continued on page 2
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NewsletterNewsletterNewsletterNewsletterNewsletter Volume 26, Number 1 February 2003
A periodical issued by the MeteoriteWorking Group to inform scientists ofthe basic characteristics ofspecimens recovered in the Antarctic.
Edited by Cecilia Satterwhite andKevin Righter, NASA Johnson SpaceCenter, Houston, Texas 77058
Inside this IssueInside this IssueInside this IssueInside this IssueInside this Issue
New Antarctic Meteorite Curator ...... 1New Meteorites ................................. 2Mars Meteorite Compendium...............2New Thin Section Procedures..............2Report on 2002-03 Field Season...........2New Meteorites......................................4Location Abbreviations and Map ..... 4Table 1: Alpha List of New
In November, I assumed the position ofAntarctic Meteorite Curator at NASA’s JohnsonSpace Center. I feel very fortunate to have theopportunity to oversee the curation of theAntarctic Meteorite Collection. This is a large anddynamic collection, augmented every year withnew, interesting and unique specimens. Themeteorite processing team here at JSC does anoutstanding job of carrying this out, and we planto continue with the many new samples returnedfrom the most recent season (see ANSMET report).I welcome any questions, comments or concerns frommembers of the community – please don’t hesitate to contact me at the address atthe end of the newsletter.
My interest in meteorites and planetary science was sparked by a summerinternship at the Lunar and Planetary Institute in 1987 just after completing college.I studied pallasite meteorites and their possible relation to the eucrite parent body(or Vesta) for a master’s thesis at the University of Michigan with Richard Arculus.Because I had an interest in fieldwork and terrestrial petrology, I pursued a doctoralthesis at the University of California at Berkeley and worked with Ian Carmichael onfield and experimental studies of the western Mexican Volcanic Belt. Since 1994, Ihave been a postdoctoral research associate with Mike Drake at the Lunar andPlanetary Laboratory of the University of Arizona. My research there has includedexperimental studies of metal-silicate equilibrium and core formation and planetarydifferentiation as well as studies of a broad range of meteorites such as metal-richchondrites, HED and martian meteorites. I also continue working on problems inbasaltic volcanism in continental and island arcs.
I was fortunate enough to have the opportunity to be a part of the 99-00ANSMET field team. The 99-00 field season returned a whopping 1042 samplesfrom the Queen Alexandra Range (Foggy Bottom and Goodwin Nunatak), LewisCliffs, Miller Range and Geologists Range.
The 1999-2000 ANSMET fieldteam near Goodwin Nunatak,from left to right: John Schutt,Peter Pesch, Phil Bland, HenningHaack, Andreas Weigel, andKevin Righter
continued on page 2
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Report on the2002-2003 FieldSeason
I’m not the right person towrite this. I’m the lazy one who stayedhome this season to play with my kids.But it falls to me to make the report,since those who actually did the workare now off climbing mountains in theAndes, surfing in Fiji, hanging out inMcMurdo, or just generally avoidingme.
Thanks to wonderful supportfrom NASA, we were finally able todeploy two ANSMET field teams thisyear. The larger main team went to theMacAlpine Hills, and did their best tofinish ANSMET’s work in the WalcottNévé region after nine previousseasons of systematic searching. Theteam of 8 included, Nancy Chabot(science lead), Jamie Pierce (safetylead), Scott Messenger, Carl Allen,Dante Lauretta, Dan Glavin, LindaWelzenbach, and Andy Caldwell (2ndTeachers Experience Antarctica partici-pant-Andy's web site describes the trip).
This team deployed to theancient Beardmore South Camp. JohnSchutt went along as a “native guide”for the first few days, to help themcover the 60 km traverse south to theGoodwin Nunataks. They started theseason there so they could finish theremaining few sweeps left from our lastseason in the region (1999-2000).
About a week later, theytraversed to MacAlpine Hills, where wehad never really invested theresources to finish searching. Thegroup did a great job at MacAlpineHills, and came within just a day or twoof completely finishing whenMurphy’s law kicked in. With just afew days left to go, they hit the “motherlode”, recovering more than 100meteorites in a single day. Then,
Ralph HarveyANSMET
New MeteoritesThis newsletter contains classifications for 439 new meteorites from the
1999, 2000 and 2001 ANSMET collections. They include samples from the QueenAlexandra Range, Bates Nunatak, Finger Ridge, Meteorite Hills, and Mt. Crean.Descriptions are given for 44 meteorites; 3 diogenites, 2 eucrites, 4 howardites, 17carbonaceous chondrites, 7 ordinary chondrites, 2 enstatite chondrites, and 9 irons.
Mars Meteorite Compendium - 2003Twenty-eight Martian meteorites, including ten from Antarctica, are the subjects
of intense study. The Mars Meteorite Compendium is continually being updated withnew data. Chuck Meyer invites corrections and/or critical comments. To find it, go tothe URL listed below:
New Thin Section ProceduresIn Spring 2002, MWG agreed that meteorite thin sections that have been
approved for and subjected to destructive analysis should be documented and recordskept of the analytical techniques used in each case. When returning a thin section,any destructive analysis should be described using the new Meteorite Sample AnalysisRecord form (MF-76) available on the website:
In addition, a sample recall was initiated for sections that have been on loanfor more than 5 years. This was done so that we do not develop situations whereinvestigators have hundreds of sections amassed in their laboratories, making futuremeteorite sample returns to JSC a daunting task. Meteorite thin sections should bereturned according to the procedures outlined at this URL:
Ob Hill near McMurdo, left to right: Kevin Righter, AndreasWeigel, Henning Haack, Ralph Harvey, Rene Martinez;kneeling is Phil Bland with Fifi.
continued from page 1
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significant snow fell, leaving them noalternative but to depart with a small arearemaining unsearched for a future visit.
All reports suggest the teamhad an amazing chemistry, and thenumbers suggest they were hard workersas well; they recovered a total of 607specimens overall.
The goal of the smaller andmore mobile reconnaissance team was toscout out poorly known or previouslyunvisited icefields and fully explore theirpotential with visits lasting a week ormore rather than a few hours or days.Their targets were the icefields in thePecora Escarpment region, which was lastvisited by ANSMET in 1991. The 4 personteam consisted of John Schutt (scienceand safety lead), Diane DiMassa, CadyColeman, and Dean Eppler. The teamdeployed to the region via South Pole
ANSMET Team: Jamie Pierce,John Schutt, Cady Coleman,Scott Messenger, Andy Caldwell, Dante Lauretta, DanielGlavin. Front Row: Diane DiMassa, Nancy Chabot, CarltonAllen, Linda Welzenbach, Dean Eppler (photo by ElizabethMorton and Daniel Glavin)
Station, and was heavily supported bya Twin Otter, allowing them to spendtime at many widely spread icefieldswithout dangerous and time-consumingtraverses. Equipped with brand-newsnowmobiles (something we haven’tseen since the 1980’s), the groupsuccessfully identified at least oneicefield with good potential, completedsearching at a couple of other smallersites, and crossed a few sites off ourpotential target list. Along the way, thereconnaissance team recovered a totalof 317 specimens, bringing the season’stotal to 924.
As an observer and “leaderat a distance,” I was constantly enviousof both teams and enormously pleasedwith the season’s results. We havevery high hopes that those of youreading this will find exciting things inthe “02” meteorite collection.
This newsletter is dedicatedto the crew of STS-107.Their dedication to science,devotion to space explora-tion, service to our country,and inspiration to people allaround the world will neverbe forgotten.
2002-2003 ANSMET Team with MeteoriteBlue Man pointing to meteorite
Andy Caldwell's web site descibing the expedition can be found at: http://tea.rice.edu/tea_caldwellfrontpage.html
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New MeteoritesFrom 1999-2001 Collection
Pages 5-23 contain preliminary de-scriptions and classifications of mete-orites that were completed since publi-cation of issue 25(2), Aug. 2002. Speci-mens of special petrologic type (car-bonaceous chondrite, unequilibratedordinary chondrite, achondrite, etc.) arerepresented by separate descriptionsunless they are paired with previouslydescribed meteorites. However, somespecimens of non-special petrologictype are listed only as single line en-tries in Table 1. For convenience, newspecimens of special petrological typeare also recast in Table 2.
Macroscopic descriptions of stony me-teorites were performed at NASA/JSC.These descriptions summarize hand-specimen features observed during initalexamination. Classification is based onmicroscopic petrography and reconnais-sance-level electron microprobe analysesusing polished sections prepared from asmall chip of each meteorite. For eachstony meteorite the sample number as-signed to the preliminary examination sec-tion is included. In some cases, however,a single microscopic description wasbased on thin sections of several speci-mens believed to be members of a singlefall.
Meteorite descriptions contained in thisissue were contributed by the followingindividuals:
Kathleen McBride, Cecilia SatterwhiteAntarctic Meteorite LaboratoryNASA Johnson Space CenterHouston, Texas
Tim McCoy, Linda Welzenbach,Gretchen BenedixDepartment of Mineral SciencesU.S. National Museum of Natural HistorySmithsonian InstitutionWashington, D.C.
Sample WeightNumber (g) Classification Weathering Fracturing % Fa % Fs
MET 00 912 ~ 27.6 H6 CHONDRITE B/C AMET 00 913 ~ 17.7 H6 CHONDRITE B/C AMET 00 914 ~ 13.0 LL6 CHONDRITE B/C AMET 00 915 ~ 11.4 LL6 CHONDRITE B/C AMET 00 916 ~ 15.3 H6 CHONDRITE C A/BMET 00 917 ~ 43.9 LL5 CHONDRITE B A/BMET 00 918 ~ 15.0 L5 CHONDRITE B/C AMET 00 919 ~ 7.4 LL6 CHONDRITE B/C AMET 00 944 19.1 L4 CHONDRITE A A 23 19MET 00 968 9.6 L4 CHONDRITE B B 23 10-20MET 001012 7.1 CM2 CHONDRITE A/B A/B 0-23 4-5MET 001038 3.7 IRON-UNGROUPED AMET 001060 9.8 DIOGENITE C C 19MET 001087 1.6 CM2 CHONDRITE A A 0-41 0-1MET 001136 3.2 IRON-IIIAB A
CRE 01 400 141.3 HOWARDITE B A 21-53
FIN 01 600 876.2 H5 CHONDRITE B B 18 16FIN 01 601 287.5 L6 CHONDRITE B A 24 20FIN 01 602 94.8 H5 CHONDRITE B B 19 16FIN 01 603 583.8 L5 CHONDRITE A B 24 20FIN 01 604 186.2 H5 CHONDRITE B B 18 16FIN 01 605 102.6 H5 CHONDRITE B B 19 16
MET 01 081 27.4 EUCRITE (UNBRECCIATED) A/B A 26-56MET 01 082 22.1 HOWARDITE B/C B 21-57MET 01 084 4.3 DIOGENITE B B 30 26MET 01 086 2.7 EUCRITE (UNBRECCIATED) A/B A/B 28-56MET 01 087 28.4 HOWARDITE B B/C 26 19-52MET 01 090 3.5 L4 CHONDRITE C A/B 25 21MET 01 091 ~ 8.6 LL6 CHONDRITE A A
MET 00 634 3.1 CV3 CHONDRITE B B 3-41 1-2MET 00 742 1.2 CV3 CHONDRITE B B 1-11 1-9MET 00 747 5.0 CV3 CHONDRITE B B 1-21 1-6MET 00 761 6.0 CV3 CHONDRITE B B 1-12 0-1
Chondrites Type - 3
MET 00 506 301.1 H3.4 CHONDRITE B A/B 4-27 2-16MET 00 552 97.3 H3.4 CHONDRITE B/C A 1-17 1-15MET 00 607 76.6 H3.4 CHONDRITE B A 3-25 7-18
MET 00 570 157.0 H3.8 CHONDRITE C B 13-19 12-17
MET 00 489 232.0 L3.6 CHONDRITE A/B A/B 14-31 4-22MET 00 621 88.8 L3.6 CHONDRITE B A/B 10-28 3-17
15
E Chondrites
MET 00 636 2.5 EH4 CHONDRITE C B 0-1MET 00 783 26.3 EH4 CHONDRITE C B 0-1
Sample WeightNumber (g) Classification Weathering Fracturing % Fa % Fs
**Notes to Tables 1 and 2:
“Weathering” Categories:
A: Minor rustiness; rust haloes on metal particles and rust stains alongfractures are minor.
B: Moderate rustiness; large rust haloes occur on metal particles and ruststains on internal fractures are extensive.
C: Severe rustiness; metal particles have been mostly stained by rustthroughout.
e: Evaporite minerals visible to the naked eye.
“Fracturing” Categories:
A: Minor cracks; few or no cracks are conspicuous to the naked eye andno cracks penetrate the entire specimen.
B: Moderate cracks; several cracks extend across exterior surfaces andthe specimen can be readily broken along the cracks.
C: Severe cracks; specimen readily crumbles along cracks that are bothextensive and abundant.
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Table 3 summarizes possible pairings of the new specimens with each other and with previously classified specimens basedon descriptive data in this newsletter issue. Readers who desire a more comprehensive review of the meteorite pairings in theU.S. Antarctic collection should refer to the compilation provided by Dr. E.R. D. Scott, as published in issue 9(2) (June 1986).Possible pairings were updated in Meteoritical Bulletins No. 76 (Meteoritics 29, 100-143), No. 79 (Meteoritics and Plan-etary Science 31, A161-174), No. 82 (Meteoritics and Planetary Science 33, A221-A239), No. 83 (Meteoritics and PlanetaryScience 34, A169-A186), No. 84 (Meteoritics and Planetary Science 35, A199-A225), No. 85 (Meteoritics and PlanetaryScience 36, A293-A322) and No. 86 (Meteoritics and Planetary Science 37, A157-A184).
CM2 CHONDRITESMET 00630, MET 00632, MET 00633, MET 00635, MET 00639, MET 00781, MET 00810, andMET 001012 with MET 00431
CO3 CHONDRITESMET 00737 with MET 00694
CV3 CHONDRITESMET 00742, MET 00747 and MET 00761 with MET 00634
EH4 CHONDRITESMET 00783 with MET 00636
EUCRITESMET 01086 with MET 01081
H3 CHONDRITESMET 00552 and MET 00607 with MET 00506
HOWARDITEMET 00800, MET 01082 and MET 01087 with MET 96500
IRON - IIIABMET 00709, MET 00724, MET 00726, MET 00812, MET 00834, MET 00864, MET 00905 and MET 001136with MET 00400
IRON - UNGROUPEDMET 001038 with MET 00428
L3 CHONDRITESMET 00621 with MET 00489
Table 3: Tentative Pairings for New Specimens
17
Petrographic Descriptions
Sample No.: QUE 99752Location: Queen Alexandra
RangeField No.: 12050Dimensions (cm): 1.5 x 1.0 x 0.5Weight (g): 1.384Meteorite Type: CM2 Chondrite
Macroscopic Description: KathleenMcBride90% of the exterior of this carbonaceouschondrite is covered with a dull, brown/black fusion crust with oxidation haloes.The interior is a soft, black matrix withrusty areas.
Thin Section (, 2) Description: TimMcCoyThe sections consist of a few small,unaltered chondrules (up to 1 mm),mineral grains and CAIs set in a blackmatrix. Olivine compositions are Fa0-23;orthopyroxene is Fs2-10. The meteorite isa CM2 chondrite.
Sample No.: MET 00489;MET 00621
Location: Meteorite HillsField No.: 12881; 13189Dimensions (cm): 7.0 x 6.5 x 2.5;
6.0 x 3.0 x 1.75Weight (g): 232; 88.835Meteorite Type: L3 Chondrite
(Estimated 3.6)
Macroscopic Description:Kathleen McBrideThe exterior of these two carbonaceouschondrites has black /brown fusioncrust. 489 has polygonal fractures and621 has a rough, pitted crust. Theinteriors range from medium gray toblack matrix. Both have numerouschondrules.
Thin Section (, 2) Description: TimMcCoyThese two meteorites, found within 1km of each other, are so similar that asingle description suffices. Thesections exhibit numerous large, well-defined chondrules (up to 3 mm) in amatrix of fine-grained silicates, metaland troilite. Weak shock effects arepresent. Polysynthetically twinnedpyroxene is extremely abundant.Olivines range from Fa10-31; pyroxenesfrom Fs3-22. The meteorites are L3chondrites (estimated subtype 3.6).
Sample No.: MET 00491Location: Meteorite HillsField No.: 12800Dimensions (cm): 6.0 x 4.5 x 3.0Weight (g): 106.568Meteorite Type: LL6 Chondrite
Macroscopic Description: KathleenMcBride50% of the exterior of this ordinarychondrite is covered by dull brown/blackfusion crust with a rough texture andpolygonal fractures. The interior is a gray,soft matrix with minor rust. Within thematrix are off white clasts and blackspecks.
Thin Section (, 2) Description: TimMcCoyThis LL6 chondrite (Fa30Fs24) is highlymetamorphosed and brecciated, withclasts reaching several millimeters. It is atypical example of the largest recognizedpairing group in the MET 00 sample set,with ~10% of the meteorites from MET 00being this same brecciated LL6.
MET 00491
MET 00489 QUE 99750-759752
MET 00621
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Sample No.: MET 00506;MET 00552;MET 00607
Location: Meteorite HillsField No.: 13365; 13347;
13152Dimensions (cm): 5.5 x 4.5 x 5.0;
4.9 x 3.9 x 2.7;7.5 x 3.0 x 2.0
Weight (g): 301.1; 97.3;76.55
Meteorite Type: H3 Chondrite(Estimated 3.4)
Macroscopic Description: KathleenMcBride and Cecilia SatterwhiteThese ordinary chondrites have darkbrown to black fusion crust containingfractures, pits and oxidation haloes. Theinteriors are rusty brown/black withmm-sized chondrules.
Thin Section (, 2) Description: TimMcCoyThese meteorites are so similar that asingle description suffices, although MET00607 was recovered ~2.5 km from theMET 00506 and MET 00552. The sectionsexhibit numerous small, well-definedchondrules (up to 2 mm) in a black matrixof fine-grained silicates, metal and troilite.Polysynthetically twinned pyroxene isextremely abundant. Weathering effectsare pervasive. Olivines range from Fa1-27and pyroxenes from Fs1-18. Themeteorites are H3 chondrites (estimatedsubtype 3.4).
Sample No.: MET 00570Location: Meteorite HillsField No.: 13516Dimensions (cm): 6.5 x 5.0 x 2.5Weight (g): 157.015Meteorite Type: H3 Chondrite
(Estimated 3.8)
Macroscopic Description: KathleenMcBride100% of the exterior is covered withbrown/black fusion crust. Somefractures and oxidation haloes arevisible. The interior is a black and rustcolored matrix with a high metal content.The matrix contains light colored clasts.Some of these clasts are stained withrust. Their sizes ranges from 2 mm – 1cm in diameter.
Thin Section (, 2) Description: TimMcCoyThe section exhibits numerouschondrules (up to 2 mm), metal andtroilite. Chondrules appear somewhataligned. Terrestrial iron oxides stain thesilicates. Olivines range from Fa13-19 andpyroxenes from Fs12-17. The meteoriteis an H3 chondrite (estimated subtype3.8).
Macroscopic Description: KathleenMcBride and Cecilia SatterwhiteThe exteriors of these carbonaceouschondrites are black with small patchesof purplish colored fusion crust. Theinteriors are a black, platy or shale likematrix with small (< 1 mm) white specks.
Thin Section (, 2) Description: TimMcCoyWe tentatively describe these as pairedgiven their find sites in a linear array ~4km in length. The MET 0063X meteoritesexhibit the shaly texture seen in otherMET 00 meteorites, particularly the MET00431 grouping (AMN Vol. 24, #2), withwhich these are spatially associated.The sections consist of a few small,unaltered chondrules (up to 1 mm),mineral grains and CAIs set in a blackmatrix. Olivine compositions are Fa0-41;orthopyroxene is Fs1-7. The meteoritesare CM2 chondrites.
MET 00... 632 639 810
MET 00506
MET 00607MET 00570 - 00574
570
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Sample No.: MET 00636;MET 00783
Location: Meteorite HillsField No.: 13571; 13522Dimensions (cm): 2.0 x 1.0 x 0.75;
3.5 x 2.0 x 2.0Weight (g): 2.509; 26.252Meteorite Type: EH4 Chondrite
Macroscopic Description: KathleenMcBrideThe exteriors of these meteorites are rustcolored. The interiors have a non-descript,brittle, rust colored matrix.
Thin Section (, 2) Description: TimMcCoyThese two meteorites are tentativelypaired. Found 4.5 km apart, they exhibitsimilar features, although these samefeatures are shared by many EH4chondrites. The sections show anaggregate of chondrules (up to 1 mm),chondrule fragments, and pyroxene grainsin a matrix of about 30% metal and sulfide.Weathering is significant, with staining ofsome enstatite grains and minor alterationof metal and sulfides. Orthopyroxene isFs0-1 and metal contains ~3 wt.% Si. Themeteorites are EH4 chondrites.
00634; 00742; 00747; 00761orite Hills; 13178;; 13034.75 x 1.25;.75 x 0.5 ;.0 x 1.0; 1.5 x 1.5 ;; 1.189;; 5.984Chondrite
: Kathleen
bonaceousck, patchynterior hasnd white
visible.
tion: Tim
und withine so similarffices. Thendrules (upark matrix., with many Fs0-9. Therites.
Sample No.: ME ME
Location: MetField No.: 1334Dimensions (cm): 2.5 x
3.5 x Weight (g): 15.8Meteorite Type: CO3
Macroscopic DescriptioMcBrideDull, black fusion crust not all of the exteriorsmeteorites. The interiochondrules of variousshades. They are hard, wicontent and are fine-grai
Thin Section (, 2) DescriMcCoyA single description sufpaired meteorites that we1.5 km of each other. consist of abundant smalchondrules, chondrule mineral grains in a dark and sulfide occur within achondrules. Olivincomposition from Fa0-33, of compositions aOrthopyroxene is Fs1-8. are CO3 chondrite of msubtype (estimated 3.6).
MET 00636
MET 00737
MET 00783
00634 ME
Sample No.: METMETMETMET
Location: MeteField No.: 13578
13101Dimensions (cm): 2.0 x 0
1.0 x 02.5 x 11.75 x
Weight (g): 3.0645.063
Meteorite Type: CV3
Macroscopic DescriptionMcBrideThe exterior of these carchondrites has 5-30% blafusion crust. The black imm-sized light gray achondrules. Some rust is
Thin Section (, 2) DescripMcCoyThese meteorites were fo2.5 km of each other and arthat a single description susections exhibit large choto 3 mm) and CAIs in a dOlivines range from Fa1-11Fa1-5, and pyroxenes frommeteorites are CV3 chond
T 00694;T 00737eorite Hills3; 131822.25 x 1.25;1.5 x 2.0
69; 23.242 Chondrite
n: Kathleen
covers most if of these twors show small light-coloredth a high metalned.
ption: Tim
fices for thesere found within The sectionsl (up to 1 mm)fragments andmatrix. Metalnd rimming thee ranges in
with a clusteringround Fa30.The meteoritesoderately high
Macroscopic Description: KathleenMcBride and Cecilia SatterwhiteShiny, rusty-black fusion crust ofvarying amounts, cover the exteriors ofthese iron meteorites.
Sample No.: MET 00739Location: Meteorite HillsField No.: 13176Dimensions (cm): 2.5 x 2.0 x 1.0Weight (g): 9.207Meteorite Type: CK4 Chondrite
Macroscopic Description: KathleenMcBride40% of the exterior is covered with adull black fusion crust that exhibits verytiny polygonal fractures. The interiorreveals 1-2 mm size gray chondrulesembedded in a soft, gray matrix.
Thin Section (, 2) Description: TimMcCoyThe section consists of large (up to 2 mm),well-defined chondrules in a matrix of finer-grained silicates, sulfides and very abundantmagnetite. The meteorite is little weathered,but extensively shock blackened. Olivine isFa30 and orthopyroxene is Fs25. Plagioclaseexhibits a broad range of compositions (An24-
76). The meteorite is a CK4 chondrite.
Thin Section Description: Tim McCoyThese 8 meteorites are all paired with eachother and with the MET 00400 pairinggroup. All exhibit the irregular shape andshiny brown surface typical of the MET00400 irons. All 8 occur along the same~6 km long linear array at the MET 00400irons. Slices were removed from MET00834 and MET 00864, surfaces werepolished and etched to reveal the internalstructure. Both meteorites exhibited thepreterrestrially, heat-altered, mediumoctahedrite structure typical of the MET00400 pairing group. The meteoritescertainly belong to that group and areprobably IIIAB irons.
MET 00864
MET 00709
MET 00812
MET 00739
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Sample No.: MET 00800;MET 01082;MET 01087
Location: Meteorite HillsField No.: 13588; 13247;
13298Dimensions (cm): 1.0 x 1.0 x 1.5;
3.0 x 2.5 x 2.0;5.5 x 3.5 x 1.5
Weight (g): 1.718; 22.143;28.406
Meteorite Type: Howardite
Macroscopic Description: KathleenMcBrideThe exterior of these achondrites hasvery small patches of black fusion crust.Areas without fusion crust expose aninterior that is gray-green in color withyellow-rust colored patches and haloes.The interiors are fine-grained, yellowochre in color with rust stained, whiteor gray inclusions and chondrules/chondrule-like spheres. 082 has areasthat are black in color.
Thin Section (, 2) Description: TimMcCoyThese meteorites are very similar andtentatively paired. The sections showa groundmass of comminuted pyroxeneand plagioclase (up to 0.5 mm) withbasaltic and orthopyroxenite clastsranging up to a few mm. Pyroxeneincludes orthopyroxene of Fs21Wo2 andfinely-exsolved (1-3 µm) orthopyroxene/augite intergrowths of Fs57Wo2 andFs24Wo40, respectively. A single olivinegrain in MET 01087 is Fa26; plagioclase isAn85-90Or0.5 and a single SiO2 grain wasanalyzed. The meteorites are howarditesand, on the basis of similarity in find sitewith MET 01082 and 01087 andpetrographic features, may be paired withMET 96500.
Sample No.: MET 00855Location: Meteorite HillsField No.: 13435Dimensions (cm): 3.0 x 2.25 x 1.25Weight (g): 9.094Meteorite Type: Diogenite
Macroscopic Description: KathleenMcBride20% of the exterior is covered with asmooth, brown fusion crust. Theinterior is yellow-orange in color. It hasa coarse, crystalline texture with platyor cubic crystals. The meteorite is veryfriable.
Thin Section (, 2) Description: TimMcCoyThe section exhibits a groundmass oforthopyroxene, with large (up to 5 mm)single orthopyroxene crystals and largemetal and sulfide grains. Orthopyroxeneis homogeneous at Fs27Wo2. The Fe/Mn ratio of the pyroxene is ~28. Themeteorite is a diogenite.
Sample No.: MET 001038Location: Meteorite HillsField No.: 12840Dimensions (cm): 1.5 x 0.75 x 0.75Weight (g): 3.694Meteorite Type: Ungrouped Iron
Macroscopic Description: KathleenMcBrideThe exterior of this iron is coveredcompletely with smooth brown/blackfusion crust with oxidation visible.
Thin Section Description: Tim McCoyThis meteorite is undoubtedly pairedwith the ungrouped iron MET 00428.Like MET 00428, it exhibits ~10-20 vol.%of rounded to elongate sulfideinclusions in a matrix of metal. Thistexture is uncommon in iron meteorites,but is known from at least one memberof group IIE (e.g., Mont Dieu). This isprobably an ungrouped iron, but maybe a member of group IIE.
MET 001038
MET 01087
MET 01082 MET 00855
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Sample No.: MET 001087Location: Meteorite HillsField No.: 12233Dimensions (cm): 1.5 x 1.0 x 0.75Weight (g): 1.597Meteorite Type: CM2 Chondrite
Macroscopic Description: KathleenMcBride40% of this carbonaceous chondrite’sexterior has thick purplish-black fusioncrust with polygonal fractures. Theinterior is a dark gray to black color witha soft matrix. White to light graychondrules are visible, <1mm in size.
Thin Section (, 2) Description: TimMcCoyThis meteorite may be paired with the otherMET 00 CM2 chondrites, but is ageographic outlier from that cluster. Thesection consists of a few small, unalteredchondrules (up to 1 mm), mineral grainsand CAIs set in a black matrix. Olivinecompositions are Fa0-41; orthopyroxene isFs0-1. The meteorite is a CM2 chondrite.
Sample No.: MET 001060Location: Meteorite HillsField No.: 12827Dimensions (cm): 2.0 x 2.0 x 1.5Weight (g): 9.839Meteorite Type: Diogenite
Macroscopic Description: KathleenMcBrideThe exterior of this meteorite is coveredwith a thick, brown-black fusion crustwith polygonal fractures. It has a roughtexture with small, shiny patches. Theinterior is composed of rusty or ruststained crystalline material. It has blackaccessory minerals and a few rounded,white inclusions. The matrix is mostlygreenish in color with rust stainedmineral grains with striations on thecrystal faces. It is also heavily fractured.
Thin Section (, 2) Description: TimMcCoyThe section is composed of large (up to3 mm) orthopyroxene crystals. Themeteorite is unbrecciated, withabundant 120° triple junctions, althoughvery minor cataclasis may have occurredalong grain boundaries. Orthopyroxenehas a composition of Fs19Wo1 with anFe/Mn ratio of ~26. The meteorite is anunbrecciated diogenite.
Sample No.: CRE 01400Location: Mt. CreanField No.: 13927Dimensions (cm): 6.0 x 5.0 x 3.0Weight (g): 141.295Meteorite Type: Howardite
Macroscopic Description: KathleenMcBrideBlack, shiny fusion crust covers 95% ofthe exterior of this meteorite. One sidehas an iridescent sheen. The interior iscomposed of soft, tan colored matrixwith numerous small clasts in a varietyof colors, textures and shapes, includingrounded white clasts, black clasts, shinyblack and green crystalline inclusions.
Thin Section (, 2) Description: TimMcCoyThe section shows a groundmass ofcomminuted pyroxene and plagioclase(up to 0.5 mm) with clasts of basalt andorthopyroxenite ranging up to 5 mm.Large orthopyroxene grains are Fs21Wo2.Orthopyroxene (Fs52Wo5) and augite(Fs25Wo40) occur together in exsolvedgrains. Pyroxene has an Fe/Mn ratio of~30. Plagioclase is An85-90Or0.5. Themeteorite is a howardite.
MET 001087
MET 001060CRE 01400
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Sample No.: MET 01084Location: Meteorite HillsField No.: 13201Dimensions (cm): 2.0 x 1.5 x 1.0Weight (g): 4.292Meteorite Type: Diogenite
Macroscopic Description: KathleenMcBride50% of the exterior of this meteorite iscovered with black fusion crust withshiny patches. The exposed interiorshows gray matrix. The interior matrixis a gray, crystalline with whiteinclusions <1 mm in size. There are afew small areas with a slight rust colorand black veins.
Thin Section (, 2) Description: TimMcCoyThe section shows a groundmass ofcoarse (up to 2 mm) comminuted pyroxene,with minor plagioclase and olivine.Orthopyroxene has a composition ofFs26Wo2; plagioclase is An88Or0.5; olivineis Fa30. The Fe/Mn ratio of the pyroxeneis ~28. The meteorite is a diogenite.
Sample No.: MET 01081;MET 01086
Location: Meteorite HillsField No.: 13031; 13859Dimensions (cm) : 3.5 x 3.5 x 1.5;
2.0 x 1.5 x 1.0Weight (g): 27.404; 2.727Meteorite Type: Eucrite
(Unbrecciated)
Macroscopic Description: KathleenMcBride90% of the exteriors are covered with ashiny, black fusion crust with a roughtexture or regmaglypt. The interiormatrices are crystalline in texture andtan to gray in color. Both contain small(<1 mm) white inclusions and blackgrains.
Thin Section (, 2) Description: TimMcCoyThese meteorites are so similar that asingle description suffices. Themeteorites are unbrecciated, medium-grained basalts composed of pyroxene(exsolved on a scale of 1-5 µm), andplagioclase with minor metal and sulfide.The meteorite is extensively shocked, withmosaicism in both pyroxene andplagioclase. Mineral compositions arehomogeneous with orthopyroxene(Fs55Wo4), with lamellae of augite(Fs28Wo36), and plagioclase (An88Or0.5).The Fe/Mn ratio of the pyroxene is ~30.The meteorites are unbrecciated eucrites.
Correction - MET 00546 (H5; Fa18Fs16)was erroneously reported in the lastNewsletter (25,2) as MET 00456. MET00456 is an LL5 chondrite that was vi-sually classified.
MET 01081
MET 01086
MET 01084
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Sample Request Guidelines
Antarctic Meteorite LaboratoryContact Numbers
Kevin RighterCuratorMail code STNASA Johnson Space CenterHouston, Texas 77058(281) [email protected]
Cecilia SatterwhiteLab Manager/MWG SecretaryMail code STNASA Johnson Space CenterHouston, Texas 77058(281) [email protected]
FAX: 281-483-5347
Requests for samples are wel-comed from research scientists of allcountries, regardless of their currentstate of funding for meteorite studies.Graduate student requests should havea supervising scientist listed to confirmaccess to facilities for analysis. Allsample requests will be reviewed in atimely manner. For sample requests thatdo not meet the curatorial guidelines theMeteorite Working Group (MWG) willreview those requests. Issuance ofsamples does not imply a commitmentby any agency to fund the proposedresearch. Requests for financial supportmust be submitted separately to the ap-propriate funding agency. As a matterof policy, U.S. Antarctic meteorites arethe property of the National ScienceFoundation, and all allocations are sub-ject to recall.
Samples can be requested fromany meteorite that has been made avail-able through announcement in any is-sue of the Antarctic MeteoriteNewsletter (beginning with 1(1) in June,1978). Many of the meteorites have alsobeen described in five Smithsonian Con-tributions to the Earth Sciences: Nos.23, 24, 26, 28, and 30. Tables containingall classified meteorites (as of February2002) have been published in several is-sues of the Meteoritical Bulletin in Mete-oritics 29, 100-143, and Meteoritics andPlanetary Science 31, A161-A174; 33,A221-A239; 34, A169-A186; 35, A199-A225; 36, A293-A322; and 37, A157-184.
or are considered special because ofunusual properties. Therefore, it is veryimportant that all requests specify boththe optimum amount of material neededfor the study and the minimum amountof material that can be used. Requestsfor thin sections that will be used indestructive procedures such as ionprobe, laser ablation, etch, or repolish-ing must be stated explicitly.
Consortium requests shouldlist the members in the consortium. Allnecessary information should be typedon the electronic form, although infor-mative attachments (reprints of publi-cation that explain rationale, flowdiagrams for analyses, etc.) are wel-come.
The Meteorite Working Group(MWG), is a peer-review committeewhich meets twice a year to guide thecollection, curation, allocation, anddistribution of the U.S. collection ofAntarctic meteorites. The deadline forsubmitting a request is 3 weeks prior tothe scheduled meeting.
Requests that are received by theMWG secretary by Feb. 27, 2003 will bereviewed at the MWG meeting March 21-22, 2003 in Houston, Tx. Requests that arereceived after the Feb. 27 deadline may bedelayed for review until MWG meets againin the Fall of 2003. Please submit yourrequests on time. Questions pertaining tosample requests can be directed to theMWG secretary by e-mail, fax or phone.
The purpose of the sample re-quest form is to obtain all informationMWG needs prior to their deliberationsto make an informed decision on the re-quest. Please use this form if possible.
The preferred method of requesttransmittal is via e-mail. Please send re-quests and attachments to:
Type MWG Request in the e-mail subject line. Please note that theform has signature blocks. The signa-ture blocks should only be used if theform is sent via Fax or mail.
Each request should accuratelyrefer to meteorite samples by their re-spective identification numbers andshould provide detailed scientific justi-fication for proposed research. Specificrequirements for samples, such as sizesor weights, particular locations (if appli-cable) within individual specimens, orspecial handling or shipping proceduresshould be explained in each request.Some meteorites are small, of rare type,
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Meteorites On-LineSeveral meteorite web site are available to provide information on meteorites from Antarctica and elsewhere in the world. Somespecialize in information on martian meteorites and on possible life on Mars. Here is a general listing of ones we have found.We have not included sites focused on selling meteorites even though some of them have general information. Pleasecontribute information on other sites so we can update the list.
JSC Curator, Antarctic meteorites http://www-curator.jsc.nasa.gov/curator/antmet/antmet.htmJSC Curator, martian meteorites http://www-curator.jsc.nasa.gov/curator/antmet/marsmets/contents.htmJSC Curator, Mars Meteorite Compendium http://www-curator.jsc.nasa.gov/curator/antmet/mmc/mmc.htmAntarctic collection http://www.cwru.edu/affil/ansmetLPI martian meteorites http://cass.jsc.nasa.gov/lpi/meteorites/mars_meteorite.htmlNIPR Antarctic meteorites http://www.nipr.ac.jp/BMNH general meteorites http://www.nhm.ac.uk/mineralogy/collections/meteor.htmUHI planetary science discoveries http://www.soest.hawaii.edu/PSRdiscoveriesMeteoritical Society http://www.uark.edu/studorg/metsocMeteorite! Magazine http://www.meteor.co.nzGeochemical Society http://www.geochemsoc.org
Other Websites of Interest
Mars Exploration http://mars.jpl.nasa.govLunar Prospector http://lunar.arc.nasa.govNear Earth Asteroid Rendezvous http://near.jhuapl.edu/Stardust Mission http://stardust.jpl.nasa.govGenesis Mission http://genesismission.jpl.nasa.govContour Mission http://www.jhuapl.edu/public/pr/CONTOUR/