[meteorite-list] Tafassasset classification
From: Bernd Pauli HD <bernd.pauli_at_meteoritecentral.com>
Date: Thu Apr 22 10:06:54 2004 Message-ID: <3D9B27CD.C772B489_at_lehrer.uni-karlsruhe.de> Svend wrote: > J. Zipfel from the MPI in Mainz says that refractory lithophiles > fractionated compared to a typical CR composition is leading to > a possible classification as primitive achondrite. Does anybody > know about a final classification yet? Hello Anne, Svend and List, In the Abstract issue of MAPS (vol. 37-7, July 2002, p. A155), Jutta Zipfel et al. published an abstract re: Tafassasset. In the discussion part, the authors state: The figure illustrates that both samples have compositions clearly fractionated from CI and other chondrite groups. Tafassasset has AI/Mg and Mn/Mg ratios similar to other primitve achondrites, indicating incipient partial melting involving mobilization of SiO2 (+/- A1203, CaO, etc.) -, P205- and S-rich melts. Although the bulk compositions are heterogeneous, characteristic element signatures (e.g., low Zn, Mn/Mg,depletion in refractory lithophile elements) e x c l u d e a relationship to CR chondrites and support pairing of Taf-Pa and Taf-Frei*. * Taf-Pa is the Paris material - Taf-Frei the Freiburg material Cheers, Bernd Received on Wed 02 Oct 2002 01:07:25 PM PDT |
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