Dho 008

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Found December 4, 1999
18° 20.5′ N., 54° 11.3′ E. Three stones with a combined weight of 2.2 kg were found in the Dhofar region of Oman and are considered to be paired. In an analysis conducted at the Vernadsky Institute in Moscow, the percent mean deviation of the FeO content in olivine (PMD-ol) was determined, a value which serves as a measure of the degree of heterogeneity of a chondrite; i.e., a chondrite with PMD-ol ≥5% is defined as unmetamorphosed or unequilibrated type 3. Dhofar 008 has a PMD-ol that is greater than 42 in at least one of the stones, indicating a highly unequilibrated petrologic grade as low as 3.0. Other stones had varying ranges prompting an initial classification of H<3.3. Further studies at the Vernadsky Institute led to the reclassification of Dhofar 008 as an L3.2/3.3. The latest studies have shown Dhofar 008 to be very similar to the transitional H/L3.6 Tieschitz:

  • average Fa and Fs contents are in the range of H chondrites
  • the range of Co in kamacite fits that of both H and L chondrites
  • bulk chemical composition in the range of L chondrites (Fe-metal = 5.8 wt%; FeO = 16.6 wt%)
  • O-isotopic composition is far from the L range, very closely resembling that of Tieschitz
  • TL results are consistent with a petrologic type of 3.2/3.3

Dhofar 008 might represent a heterogeneous, unequilibrated mixture from different magma reservoirs on the L chondrite parent body, or it could derive from an intermediate chondrite parent body similar to that of Tieschitz. Dhofar 008 contains mostly porphyritic chondrules, sometimes strongly zoned, in which the olivine fayalite content varies widely. Low-Ca pyroxene is the most common silicate, with the presence of minor pigeonite and augite. The meteorite has been shocked to stage S3 and terrestrially weathered to grade W2. The specimen of Dhofar 008 shown above is a 1.3 g thin partial slice showing a darkened portion created by weathering underneath the soil. The photo below shows one of the complete stones in situ.

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