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| Allan Hills A77086 | |||||||||||||||||||||||||
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| Basic information | Name: Allan Hills A77086 This is an OFFICIAL meteorite name. Abbreviation: ALHA77086 This meteorite may also be called Allan Hills 77086 (ALH 77086) in publications. Observed fall: No Year found: 1977 Country: Antarctica [Collected jointly by ANSMET (US) and NIPR (Japan)] Mass:  19.4 g | ||||||||||||||||||||||||
| Classification history: |
This is 1 of 11150 approved meteorites (plus 22 unapproved names) classified as H5. [show all] Search for other: H chondrites, H chondrites (type 4-7), Ordinary chondrites, and Ordinary chondrites (type 4-7) | ||||||||||||||||||||||||
| Writeup |
Writeup from AMN 4(1):
Sample No.: ALHA77086 Location: Allan Hills Field No.: 77122759 Weight (gms): 19.44 Meteorite Type: H5 Chondrite
Physical Description: The overall color o the sample is brownish-black and severely weathered. About 30% of the meteorite's surface is covered with remnants of fusion crust. The remainder of the surface represents three fracture faces. From field photographs it appears that the T surface was on the ice. The sample was difficult to chip. The fresh interior surface is not as weathered as the exterior surface. The longest dimension of the sample is approximately 2.5 cm.
Petrographic Description: Brian Mason Chondrules numerous, some well-defined, others irregular in form and tend to merge with the groundmass. They range from 0.3-1.2 mm in diameter, and show a variety of types, the commonest being porphyritic olivine, barred olivine, and radiating or fine-grained pyroxene. Fusion crust is present on one edge. The section is pervaded by yellow-brown limonitic staining, and patches and veinlets of brown limonite are present. Microprobe analyses show olivine (Fa19) and orthopyroxene (Fs17) of uniform composition; some small grains of sodic plagioclase were detected. | ||||||||||||||||||||||||
| Data from: MB76 Table 2 Line 72: |
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| References: | Published in Antarctic Meteorite Newsletter 4(1) (1981), JSC, Houston Published in Meteoritical Bulletin, no. 76, Meteoritics 29, 100-143 (1994)
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Geography:
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Statistics: This is 1 of 43856 approved meteorites from Antarctica (plus 3802 unapproved names) | ||||||||||||||||||||||||
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