THE METEORITICAL BULLETIN Announcement 86-1, April 5, 2002 Sara Russell, Editor (firstname.lastname@example.org) Jutta Zipfel, Assoc. Ed. for Saharan Meteorites (email@example.com) Jeffrey N. Grossman, Assoc. Ed. for Web (firstname.lastname@example.org) Monica M. Grady, Co-Editor Dhofar 378 1809.5' N, 5406.8' E Oman Found 2000 June 17 Martian meteorite (basaltic shergottite) A single stone of 15 g, covered with fresh black fusion crust, was recovered by an anonymous finder within the province of other Dhofar meteorites. Classification and description: (Y. Ikeda and M. Kimura, Dept. of Materials and Biological Sciences Ibaraki; H. Takeda, Chiba): It has a doleritic or microgabbroic texture, and the grain sizes of the main minerals (pyroxenes and plagioclase glass) are about 1 mm across. It consists mainly of ferroan pyroxenes (augite and pigeonite), and plagioclase glass with quenched plagioclase rims. Minor minerals are hedenbergite, pyroxferroite, fayalite, silica, Ti-rich magnetite, ilmenite, sulfide, phosphate, and rhyolitic glass. The Fe/(Mg+Fe) ratios of pyroxenes (augite and pigeonite) range from 0.40 to more than 0.90, those of hedenbergite from 0.97 to 0.99, and olivine from 0.90 to 0.98. The original plagioclase grains were transformed to plagioclase glass (An35 to An55) by an intense impact shock, then quenched plagioclase of the same composition a few tens of mm up to one hundred mm in width at the boundaries between the plagioclase glass and other minerals. Oxygen isotopic composition (T.K. Mayeda and R.N. Clayton, UChi): d18O == +4.46 permil, d17O == +2.52 permil. This meteorite was recovered from an area near the Dhofar 019 basaltic shergottite, but the two meteorites are probably not paired. Dhofar 019 is doleritic and contains olivine grains with Fe/(Mg+Fe) ratios of 0.4-0.75, whilst these seem to be absent from Dhofar 378. Pyroxenes in Dhofar 019 are more magnesian than in Dhofar 378. Specimens: type specimens 0.445 g & 0.054 g, Ibaraki; 2.74 g MPI; main mass is with the anonymous finder.
See also abstracts from the 2002 LPSC.
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