SHRIMP U-Pb zircon dating was undertaken on two samples of Dokhan Volcanics from the type area at Gebel Dokhan, north Eastern Desert, Egypt. A quartz andesite from the Imperial Porphyry unit has a weighted 206Pb/238U age of 593 f 13 Ma (20). A sample of grey andesite, from 450 m lower in the succession, has a weighted 206Pb/23*U age of 602 + 9 Ma (20). These ages are interpreted to record the t...

Kepsut-Dursunbey volcanic field (KDVF) is located in NW Turkey and contains various products of the post-collisional Neogene magmatic activity. Two distinct volcanic suites have been recognized; the Kepsut volcanic suite (KVS) and the Dursunbey volcanic suite (DVS). The KVS includes basaltic trachyandesitebasaltic andesite-andesite lavas and associated pyroclastic rocks. The DVS consists of dac...

T w o series of pyroxenes have been found in a layered teschenite sill, 22 m thick, emplaced in Late Permian coal measures in the Sydney Basin, New South Wales, Australia. The sill consists of 12 m of homogeneous teschenite, overlain by 6 m of picrite, then by 4 m of a layered sequence. The layering unit of this sequence is teschenite, a pyroxene-rich layer and a narrow leucocratic band. A whol...

The long-standing controversy about the origin of magnetite-(apatite) mineral deposits pertains to how they form. Pleistocene El Laco deposit in northern Chile is a critical location because host andesite contains immiscible melt inclusions trapped plagioclase and clinopyroxene phenocrysts that reveal involvement melts evolution Volcanic System hosting mineralization. We present results from fi...

Despite the absence of an apparent triangular pattern in crystal structure, we observe unusually well pronounced 1/3 magnetization plateaus quasi one-dimensional Ising spin chain compound CoGeO$_3$ which belongs to class pyroxene minerals. We succeeded uncovering detailed microscopic structure plateau phase by means neutron diffraction. observed changes initial antiferromagnetic zero-field that...

Al Huwaysah 010 is an ungrouped achondrite meteorite, recently referred to as a brachinite-like meteorite. This showing fine-grained assemblage of low-Ca pyroxene and opaque phases, strongly reduced in comparison other brachinites. The occurrence some tiny plates graphite oldhamite this meteorite suggests that partial melt residue has experienced further reduction process. Olivine, the most abu...

Multiple chondritic meteorite fragments have been found in two sedimentary rock samples from an end-Permian bed at Graphite Peak in Antarctica. The Ni/Fe, Co/Ni, and P/Fe ratios in metal grains; the Fe/Mg and Mn/Fe ratios in olivine and pyroxene; and the chemistry of Fe-, Ni-, P-, and S-bearing oxide in the meteorite fragments are typical of CM-type chondritic meteorites. In one sample, the met...