Systematics: Achondrites, Primitive Achondrites, Irons & Stony Irons Classification

PART I: CHONDRITES, METACHONDRITES
PART III: MARTIAN METEORITES—GEOCHEMICAL CLASSIFICATION
PART IV: DIOGENITES—IUGS TAXONOMY
PART V: ENSTATITE CHONDRITES—SUBGROUP CLASSIFICATION

PRIMITIVE ACHONDRITES

INCIPIENT DIFFERENTIATION
(including restites from very low degree partial melts)

ACAPULCOITE–LODRANITE CLAN (5 metamorphic subgroups, after Floss, 2000; Patzer et al., 2003)
1. Primitive Acapulcoites [Se >12–13 ppm] (e.g. ALHA77081, GRA 98028 [‘A chondrite’, highly primitive {~6 vol% chondrules}], GRV 020043 [‘A chondrite’, highly primitive {type 4, ~62 vol% chondrules; photo credit: Li et al., 2018}], Monument Draw [‘A chondrite’], Y-74063 [‘A chondrite’])
2. Typical Acapulcoites [Se ~5–12 ppm] (e.g. Acapulco, ALH 78230, ALHA81261, Dho 125 and pairings, Dho 290, Dho 312, FRO 95029, NWA 1617, NWA 2656 and pairings, NWA 2775, TIL 99002)
3. Transitional Acapulcoites [Se <5 ppm] (e.g. ALHA81187, EET 84302, FRO 93001, GRA 95209, LEW 86220, MAC 041193, NWA 2627)
4. Lodranites [K <200 ppm, Grain size 500+ µm] (e.g. GRA 95209, Lodran, MAC 88177, NWA 468 [anom, metal-rich], NWA 2235, NWA 3341, NWA 4448, NWA 4478, NWA 4529, NWA 4663, NWA 4833, NWA 4875 [possibly paired with NWA 4478], Willcox Playa 010 [highly reduced])
5. Enriched Acapulcoites [addition of feldspar-rich melt] (e.g. FRO 93001, LEW 86220)
BRACHINITE CLAN (2 divisions, after Goodrich et al., 2017)
1. Brachinites (e.g. ALH 84025, Brachina [most primitive], Eagles Nest, EET 99402/7, Hughes 026 [syn: Australia 1], NWA 3151, NWA 4969 and pairings, NWA 4876, NWA 5191 [possibly paired with NWA 3151], NWA 5471, NWA 6308, Reid 013 [a portion under the synonyms Nova 003 and Window Butte], Reid 027)
2. Brachinite-like (e.g. Divnoe, MIL 090206 and pairings, MIL 090340, NWA 595, NWA 1500, NWA 4042, NWA 6112, Zag (b))
WINONAITES (3 metamorphic subgroups; adapted from Floss, 2000 and Patzer et al., 2003)
1. Primitive Winonaites (e.g. Dhofar 1222 [‘W chondrite’ {~4 vol% chondrules}], Mount Morris [‘W chondrite’], NWA 516, NWA 8614, Pontlyfni [‘W chondrite’])
2. Typical Winonaites (e.g. Fortuna, HaH 193, NWA 1457, Winona)
3. Evolved Winonaites (e.g. NWA 2993, Tierra Blanca)
UREILITES (2 divisions)
1. Monomict/Unbrecciated (4 mineralogical types)
A. Olivine-Pigeonite, mantle residue (e.g. DaG 084, DaG 868, Dhofar 979, Haverö, Kenna, Novo Urei, NWA 2624, NWA 7630 [dunitic]; intermediate: e.g. Hajmah (a))
B. Olivine–Orthopyroxene, mantle residue (e.g. EET 87511 and pairings, EET 87517, LEW 85440 and pairings, MET 01085, NWA 11511 [anom, opx-rich, sodic plag.-bearing], Y-74659, Y-791538)
C. Olivine–Augite, mantle cumulate or paracumulate (2 categories)
i. Plagioclase-free (e.g. Almahata Sitta #15, ALH 82106 and pairings, Calama 001, EET 96293 and pairings, FRO 90054 and pairings, HaH 064, Hughes 009, LEW 88774, META78008, NWA 3222, Ramlat as Sahmah 530 [photo courtesy of Marcin Cimala], Y-74130)
ii. Plagioclase-bearing (e.g. AhS MS-MU-012)
D. Trachyandesite (e.g. AhS MS-MU-011, AhS MS-MU-035)
2. Polymict (2 mineralogical types)
A. Shallow regolith fragmental breccia (e.g. Almahata Sitta)
B. Deep regolith fragmental breccia (e.g. DaG 319 and pairings, EET 83309, Nilpena, North Haig, Reid 016)
ENSTATITES (Pilski et al., 2011) (e.g. Zakłodzie [or MR/IMB])
SILICATE INCLUSIONS IN IRONS (Includes silicates from the IAB complex (e.g. Caddo County, Four Corners, Landes), and from groups IIE (e.g. Netshaëvo, Techado, Watson) and IVA (e.g. São João Nepumuceno, Steinbach)
UNGROUPED PACS (e.g. Dhofar 500, NWA 7312 [CR-like; abstract], NWA 11042 [L-like; abstract 1, 2; cut face photo courtesy of Abdelhadi Aithiba], QUE 94204, Sah 03500, Tafassasset [CR-like])

ACHONDRITES

VESTAN SUITE

HOWARDITES (2 subdivisions)
1. Fragmental Breccia (e.g. Luotolax, Old Homestead 001, NWA 1182, NWA 1282~NWA 1664~NWA 1769)
2. Regolith Breccia (e.g. Bholghati, Bununu, EET 87513, GRO 95535, GRO 95602, Jodzie, Kapoeta, LEW 85313, Lohawat, Malvern, MET 00423)
EUCRITES (2 subdivisions)
1. Monomict or genomict breccia (2 categories)
A. Gabbroic, Cumulate (e.g. Binda [unbr], Moore Co., NWA 1836, NWA 1925, NWA 11729 [anom, highly ferroan; abstract], SaU 493 [anom, hematite-bearing], Serra de Magé, Talampaya, Vissannapeta)
B. Basaltic, Non-cumulate (3 series; Yamaguchi et al., 2009)
i. Main Group–Nuevo Laredo Trend (e.g. Camel Donga, Igdi, Lakangaon, Nuevo Laredo, NWA 999, NWA 3152, Sah 02501, Sioux County)
ii. Stannern Trend (e.g. Stannern, Bouvante, LEW 88010, NWA 4523, PCA 82501)
iii. Residual (e.g. A-87272, Agoult, DaG 945, NWA 2362)
2. Polymict, <10% magnesian orthopyroxenite (e.g. Dho 007, Millbillillie [unbr], NWA 10674 [anom], Smara, Padvarninkai, PCA 91006)
DIOGENITES ultramafic composition—olivine+orthopyroxene ≥90 vol% (7 mineralogical types [IUGS])
1. Orthopyroxenitic (≥90 vol% opx) (e.g. Bilanga, Dhofar 778 [anom], Johnstown, LAP 02216, LEW 88679, MET 00424, NWA 1821, NWA 3106, NWA 3329, QUE 99050, Tatahouine)
2. Olivine–Orthopyroxenitic (opx + 10–40 vol% olv) (e.g. ALHA77256, GRA 98108, LEW 88679, NWA 5312, NWA 5405)
3. Harzburgitic (>40 vol% olv) (e.g. ALHA77256, EETA79002, GRA 98108, LAP 03979, NWA 1459, 1877 and pairings, NWA 4223, NWA 5480, NWA 6157, NWA 7370)
4. Dunitic (≥90 vol% olv) (e.g. MIL 03443, NWA 2968)
5. Noritic (opx + <5 vol% olv + >10 vol% plg) (e.g. NWA 5315, NWA 6928)
6. Polymict (dun ± harz ± opx ± euc (<10 vol%) (e.g. ALH 85015, LEW 88008, NWA 1239, NWA 1648, NWA 4473, NWA 6945 [w/ noritic clasts])
7. Genomict (all clasts fractionally related) (e.g. EETA79002)
TRANSITIONAL diogenites/magnesian cumulate eucrites (e.g. MIL 07003, QUE 93009, Yamato Type B diogenites)

MARTIAN SUITE Petrological and Mineralogical Classification (7 subdivisions)

1.Basaltic (6 categories)
A. Pyroxene-phyric basalt (e.g. Dho 378, EETA79001B, Los Angeles, NWA 480/1460 [diabase], NWA 1669, NWA 3171, QUE 94201, Shergotty, Zagami)
B. Olivine-phyric basalt (e.g. Dho 019, EETA79001A, NWA 1068 and pairings, Y-980459 [ol-websterite], NWA 4468, NWA 5789, NWA 6234, NWA 10170, SaU 005 and pairings, Tissint)
C. Olivine–orthopyroxene-phyric basalt (e.g. DaG 476 and pairings, NWA 1195, NWA 2046, NWA 2626)
D. Olivine–plagioclase-phyric basalt (e.g. NWA 7635 [photo; poss. launch paired with NWA 8159])
E. Pigeonite-phyric basalt (e.g. NWA 10414)
F. Augite-rich basalt (e.g. NWA 8159 [poss. launch paired with NWA 7635])
2. Gabbroic/Microgabbroic (e.g. NWA 7320, NWA 8637, NWA 10567, NWA 10761, NWA 11300, NWA 11509)
3. Poikilitic (formerly lherzolitic, bimodal gabbroic intrusive; 2 categories)
A. Pyroxene-oikocrystic (e.g. ALHA77005, LEW 88516, NWA 1950, NWA 4797, NWA 7397, NWA 10961 [photo courtesy of Ben Hoefnagels], RBT 04261/2, Y-793605, Y-984028 [reg. brec.])
B. Plagioclase–olivine–clinopyroxenite (e.g. NWA 2646)
∗See alternative Geochemical Classification Schemes for the martian basaltic, gabbroic, and poikilitic meteorites based on elemental, isotopic, and other trends.
4. Orthopyroxenite (e.g. ALH 84001)
5. Olivine–clinopyroxenite (e.g. Caleta el Cobre 022, Governador Valadares, Lafayette, MIL 03346 and pairings, Nakhla, NWA 817, NWA 998, NWA 5790/6148, NWA 10153 and pairings, Y-000593/749/802)
6. Polymict Regolith Breccia (e.g. NWA 7034/7533 and pairings [alkali-rich])
7. Dunite (e.g. Chassigny, NWA 2737, NWA 8694)

LUNAR SUITE after List of Lunar Meteorites
Randy L. Korotev—Washington University in St. Louis

Sampling the Feldspathic Highlands Terrane, Procellarum KREEP Terrane, South Pole-Aitken Terrane, and associated maria
1. FELDSPATHIC BRECCIAS (4 [or more] lithological types)
a. Regolith breccia (e.g. DaG 262)
b. Fragmental breccia (e.g. Dho 081)
c. Impact-melt breccia (e.g. Dho 302 and pairings, NWA 482)
d. Granulitic brecia (e.g. Dhofar 026, Dhofar 733, NWA 4483 and pairings, NWA 5744)
2. MAFIC, Th-RICH, IMPACT-MELT BRECCIAS (e.g. NWA 4472/4485 [KREEP-rich; 6.9 ppm Th], Dhofar 925/960/961/SaU 449 [KREEP components; ~2 ppm Th], SaU 169 [KREEP-rich w/ 13 vol% 2a component; 32.7 ppm Th])
3. MINGLED BRECCIAS (2 categories)
a. Predominantly feldspathic (e.g. Calcalong Creek [25% KREEP-norite; 4.3 ppm Th], Dho 1180 [KREEP clast; 0.9 ppm Th], NWA 2995, SaU 169, Y-983885 [KREEP clasts; 2 ppm Th])
b. Predominantly basaltic (e.g. Apollo 15 & 17 regolith samples, Kalahari 008/009, NWA 773 clan [w/ 1a, 1b, 4, and KREEP-rich components], NWA 3136, QUE 94281)
4. MARE BASALTS (unbrecciated) (e.g. Dho 287 [w/ 5 vol% 1a component], LAP 02205 and pairings, NEA 003, NWA 032/479, NWA 4734, NWA 4898, NWA 12008)

OTHERS

ANGRITES (3 subgroups, possibly representing two daughter asteroidal bodies)
1. Basaltic/Quenched; daughter 1 (e.g. Asuka 881371/12209 [picritic], D’Orbigny, LEW 87051 [picritic], NWA 1296, NWA 1670 [picritic], NWA 7203 [photo courtesy of Labenne Meteorites], NWA 7812 [picritic], NWA 12320, Sah 99555, Y-1154)
2. Subvolcanic/Hypabyssal; daughter 2 (e.g. LEW 86010, NWA 4590, NWA 10463, NWA 12004)
3. Plutonic/Metamorphic; daughter 2 (e.g. Angra dos Reis [pyroxenitic], NWA 2999 and pairings [peridotitic], NWA 4801, NWA 8535 [dunitic; photo courtesy of Habib Naji])
AUBRITES (2 groups/parent bodies)
1. Main-group, light-REE-depleted (e.g. Aubres, Cumberland Falls, Mayo Belwa [IMB], NWA 1235 [An], NWA 4537, NWA 4799, NWA 4832, NWA 4871 [possibly paired with NWA 4799], NWA 6350 [paired with NWA 5217], NWA 6675, Peña Blanca Spring)
2. Metal-rich, light-REE-enriched (e.g. Larned [anom], Mount Egerton [anom], NWA 2526 [Enst achon])
UNGROUPED ACHONDRITES (e.g. Bunburra Rockhole [eucrite-like, possibly related to A-881394; photo courtesy of Imperial College London], Dhofar 732 [olv–opx], Ibitira [eucrite-like], AhS MS-MU-036 [enst achon], NWA 011 and pairings, NWA 1240, NWA 1840 [enst achon], NWA 2824 [eucrite/Ibitira-like], NWA 4284 [L-like; abstract], NWA 4741, NWA 5400 and pairings, NWA 5517 [possibly related to NWA 7325; abstract], NWA 5721, NWA 5958, NWA 6698 [LL-like diorite; abstract], NWA 6704 and pairings [CC-related], NWA 6962, NWA 7325, NWA 7822 [CV-related], NWA 7835 [photo courtesy of Stefan Ralew], NWA 8054 [abstract; prob lod-anom]; NWA 8671 [eucrite-like; abstract], NWA 8777 [abstract], NWA 11119 [possibly related to NWA 7325; photo courtesy of Carl Agee; NWA 11187 [ureilite-like; abstract], NWA 11575 [LL-like trachyandesite; abstract 1, 2], NWA 12217 [dunite breccia; abstract], NWA 12338 [eucrite-like; abstract], Pasamonte [eucrite-like], PCA 82502/91007 [eucrite-like], Shallowater [enst achon])

STONY-IRONS

MESOSIDERITES subgroupings after Hewins (1984)
based on metamorphic grade (0–4) and orthopyroxene content (A–C)

0B (e.g. NWA 1878)
1A (e.g. Vaca Muerta, Crab Orchard, Patwar, Mount Padbury, Barea)
1B (e.g. Chinguetti, ALHA77219 and pairings)
2A (e.g. Clover Springs, Veramin, NWA 1242)
2B (reclassified as 4B under Hewins) (e.g. NWA 1817, NWA 6436)
2C (e.g. NWA 1827, JaH 203 and pairings)
3A (e.g. Emery, Lowicz, Morristown, NWA 1961)
3B (reclassified as 4B)
4A (e.g. Estherville [3/4A])
4B (e.g. Bondoc, Mincy)

PALLASITES 3 groups along with ungrouped members
(Mittlefehldt, 1999; Wasson et al., 2002; Wasson and Choi, 2003; Hsu, 2003; Gregory et al., 2016)

1. Main-group (2 subgroups [after Ali et al., 2018] and subgroup not yet determined)
A. high-Δ17O-bearing (ave. –0.166 [±0.014] ‰) (e.g. Acomita, Ahumada, La’gad 002 [anom metal; plessite], Brenham [anom metal; Ge, Ga], Finmarken, Hambleton, Huckitta [anom metal; Ge, Ga, Pt, W, Ir], Imilac, Jay Bird Springs, Marjahlati, Otinapa, Pallasovka, Somervell County, South Bend, Springwater [anom silicates; Fa, P-ol], Sterley, Thumrayt 001)
B. low-Δ17O-bearing (ave. –0.220 [±0.009] ‰) (e.g. Brahin [anom silicates; P-ol], Esquel, Fukang, Giroux, Hambleton, Krasnojarsk [anom metal; Co, As, Sb, Ni, Cu], Mount Dyrring, Newport, Seymchan [anom metal; Ir])
*subgroup not yet determined (e.g. Albin, Argonia [anom metal; Ir], Cumulus Ridge 04071 and pairings [anom metal; Au, Ge], Conception Junction [anom metal; Ni, Cu, Co, Ga, As, Ir], Glorieta Mountain [anom metal; Ge, Ga], Jepara, Mineo, Mount Vernon, Omolon [anom metal; kamacite], Pavlodar [anom metal; Au], Phillips County [anom silicates; Fa, FeS, Ni], Rawlinna 001 [anom silicates; Fa, Ni, Co, Cu, P-ol], Sericho, Theil Mountains, Zaisho [anom silicates; Fa, P-ol])
2. Eagle Station group (possibly CK- or CO-related) (e.g. Cold Bay, Eagle Station, Itzawisis, Karavannoe, Oued Bourdim 001)
3. Pyroxene group (e.g. LoV 263, NWA 1911/Zinder duo, NWA 10019, ‘Vermillion Pallasites’ [Choteau, Vermillion, Y-8451])
Ungrouped (e.g. Milton [‘CX’ trend])

IRONS

CHEMICAL GROUPS

IAB complex (Wasson and Kallemeyn, 2002)
1. main group (e.g. Campo del Cielo, Canyon Diablo, DaG 962, Landes, Odessa)
2. subgroup sLL (e.g. Toluca, Deport, NWA 2311, NWA 8346, Zagora)
3. subgroup sLM [formerly IIIC](e.g. Carlton, Lamesa, Maltahöhe, NWA 2680)
4. subgroup sLH [formerly IIID](e.g. Dayton, Freda, NWA 3206, Tazewell)
5. subgroup sHL (e.g. Chebankol, Hassi-Jekna, Lonaconing, NWA 2151, NWA 3200/4706/4710, NWA 8348, NWA 11577, Quarat al Hanish)
6. subgroup sHH (e.g. ALHA80104, Garden Head, Gay Gulch, Kofa, Mount Magnet, NWA 4701)
7. Udei Station grouplet (e.g. Caddo County, Four Corners, Udei Station, Zagora)
8. Pitts grouplet (e.g. Pitts, Woodbine)
9. Algarrabo duo (Algarrabo, Livingston)
10. Mundrabilla duo (Mundrabilla, Waterville)
11. Britstown duo (Britstown, EET 87506)
12. NWA 468 duo (NWA 468, GRV 98003) note: NWA 468 has been reclassified as anomalous lodranite; Sanborn et al., 2014)
13. Twin City duo (Twin City, Santa Catharina)
14. IAB-related irons (e.g. Georgetown, NWA 4861 [sHL-related], NWA 5804 [ungr], Oktibbeha County)
IC (e.g. Arispe)
IIAB (e.g. Auburn, Carver, Coahuila, Guadalupe y Calvo, Sikhote Alin)
IIC (e.g. Ballinoo, Cratheús [1950], Darinskoe, Kumerina, Perryville, Salt River, Unter Mässing, Wiley)
IID (e.g. Carbo, Needles)
IIE (2 categories [after McCoy, 1995; Van Roosbroek et al., 2015])
1. With silicate inclusions (2 metamorphic subtypes)
A. chondritic/unfractionated (e.g. Garhi Yasin, Mont Dieu, Netshaëvo, RBT 04186, Techado, Watson 001 [evolved, impact melt], Y-791093 [transitional])
B. differentiated/fractionated (e.g. Elga, Colomera, Kodaikanal, Miles, NWA 5608, Tarahumara, TYR 05181, Weekeroo Station)
2. Without silicate inclusions (e.g. Arlington, Barranca Blanca, EET 83390, Leshan, NWA 6716, Sah 03505, Tobychan, Verkhne Dnieprovsk)
IIF (e.g. Corowa, Del Rio, Monahans [1938], Repeev Khutor)
IIG (e.g. Bellsbank, Guanaco, La Primitiva, Tombigbee River, Twannberg)
see THE BELLSBANK QUINTET: The Consummation of a New Iron Group—IIG
IIIAB (e.g. IIIA: Cape York, Wabar, Tambo Quemado; IIIAB: Whitecourt)
IIIE (e.g. Aletai [anom], Coopertown, Willow Creek)
IIIF (e.g. Klamath Falls, Nelson Co., St. Genevieve Co.)
IVA (e.g. Bishop Canyon, Descoberto [anom], Gibeon, NWA 5289, Page City, Säo Joäo Nepomuceno [anom], Steinbach [anom])
IVB (e.g. Hoba, Santa Clara)
IVC (after Litasov et al., 2017) (e.g. ALH 77255, Alikatnima, Babb’s Mill [Blake’s], Chinga, Deep Springs, Onello, Shingle Springs)
SULFIDE-IRONS (e.g. HOW 88403, MET 00428 [H chon], Sacramento Wash 005 [H chon])
UNGROUPED IRONS (e.g. NWA 176, Sombrerete, Taza, Willamette)

PART I: CHONDRITES, METACHONDRITES
PART III: MARTIAN METEORITES—GEOCHEMICAL CLASSIFICATION
PART IV: DIOGENITES—IUGS TAXONOMY
PART V: ENSTATITE CHONDRITES—SUBGROUP CLASSIFICATION

You must collect things for reasons you don’t yet understand.
Daniel J. Boorstin – Librarian of Congress


© 1997–2019 by David Weir

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