MetSoc Home            Publications            Contacts  
Search the Meteoritical Bulletin Database
Last update: 22 Sep 2022
Search for: Search type: Search limits: Display: Publication:
Text help
Starts with
Sounds like
Falls  Non-NWAs
What's new
  in the last:
Include past classifications in search
Limit to approved meteorite names
Search text:  
Pecora Escarpment 91002
Basic information Name: Pecora Escarpment 91002
     This is an OFFICIAL meteorite name.
Abbreviation: PCA 91002
Observed fall: No
Year found: 1991
Country: Antarctica [Collected by US Antarctic Search for Meteorites program (ANSMET)]
Mass:help 210 g
Antarctic Meteorite Newsletter:  AMN 15(2)  (1992)  Chondrite-ung
AMN 17(1)  (1994)  Carlisle Lakes-like
Meteoritical Bulletin:  MB 76  (1994)  R
NHM Catalogue:  5th Edition  (2000)  R3-6
MetBase:  v. 7.1  (2006)  R3.8-6
Antarctic Meteorite Newsletter:  AMN 31(1)  (2008)  R3.8-6
Recommended:  R3.8-6    [explanation]

This is 1 of 4 approved meteorites classified as R3.8-6.   [show all]
Search for other: Rumuruti chondrites, Rumuruti chondrites (type 3)
Writeup from AMN 15(2):

Sample No.: PCA91002

Location: Pecora Escarpment

Field Number: 5499

Dimensions (cm): 7.8 x 4.9 x 4.7

Weight (g): 210.2

Meteorite Type: Ungrouped chondrite (similar to ALH85151 and Carlisle Lake)


Macroscopic Description: Robbie Marlow

One third of PCA91002 is covered with dull, dark brown fusion crust. Evaporite deposit is present on the interior and exterior surfaces. The interior matrix is fine-grained, dark gray, and contains numerous inclusions which have a wide range of sizes. Sulfides are present.


Thin Section (,8) Description: Brian Mason

The section shows numerous polycrystalline silicate clasts (up to 1.2 mm in maximum dimension), some small chondrules (up to 0.5 mm across), and mineral grains in a finely-granular gray matrix. A moderate amount of sulfides is present, much of it as minute grains disseminated through the matrix. No nickel-iron was seen. The meteorite appears to be unweathered. Microprobe analyses show olivine and pyroxene of variable composition. Olivine compositions show a prominent peak at Fa39, with occasionally more magnesian grains (CV FeO is 44). The pyroxene is almost entirely low-Ca: Wo0.3-5, Fs1-28; one grain of diopside, Wo45Fs12, was analyzed. Maskelynite is present in a few clasts. The sulfides are mainly pentlandite, with minor troilite. This meteorite cannot readily be placed in any of the recognized chondrite classes, and hence is recorded as ungrouped. It is very similar to ALH85151 and Carlisle Lake (Geochim. Cosmochim. Acta, v. 53, p. 3035, 1989; v. 55, p. 2657, 1991).


Data from:
  Table 2
  Line 4864:
Origin or pseudonym:Main
Mass (g):210.2
Weathering grade:A/B
Fayalite (mol%):1-44
Ferrosilite (mol%):1-28
Comments:NTL=28.1±0.2; 91002 pairing group
Search for specimens in the Smithsonian Institution collection (U.S.):   
    Require SI photo
Search for this meteorite in the NASA/JSC database (U.S.):   
References: Published in Antarctic Meteorite Newsletter 15(2) (1992), JSC, Houston
Published in Meteoritical Bulletin, no. 76, Meteoritics 29, 100-143 (1994)
Find references in NASA ADS:
Find references in Google Scholar:

     Catalogue of Meteorites:   (85° 38'S, 68° 42'W)
     Recommended::   (85° 40' 1"S, 67° 53' 11"W)
Note: the NHM and MetBase coordinates are 7.9 km apart

     This is 1 of 43499 approved meteorites from Antarctica (plus 3802 unapproved names)
Proximity search:
Find nearby meteorites: enter search radius (km):

Direct link to this page