The structure refinement of a hastingsite (CI 0.91 p.f.u.) from West Ongul Island, Liitzow-Holm Bay, East Antarctica, has been carried out in order to characterise the effect of CIon the crystal structure. The composition of the CI-rich hastingsite is KO.69Nao.26Ca1.99Mg1.09Fe2+ 2.71Fe3+O.92MnO.\l4 Tio.lOAI2.31Sis.R30220Ho.99Clo.91Fo.10with unit cell parameters a 9.962(3), b 18.283(7), c 5.372(...

The rarity of Devonian tetrapods and the absence of tetrapods during the first 14 million years of the Mississippian (Romer’s Gap) have inspired hypotheses of fish-tetrapod evolutionary transition as an escape from difficult habitats such as deserts or stagnant waters. These hypotheses and Romer’s Gap are tested here using depth to calcic horizon in paleosols of the northern Appalachians as a p...

Although various episodes of wet Quaternary climates have been suggested in studies of the Negev Desert, here we demonstrate that Reg soils, developed on flat alluvial surfaces and sensitive to minor changes in precipitation, indicate that the southern Negev has been permanently hyperarid at least since the middle Pleistocene. The wetter episodes were restricted to the northern Negev, currently...

maherabad prospect area, which is studied in detail, is the first porphyry cu-au mineralization in the east of iran. based on relation of mineralization with subvolcanic intrusive bodies mostly monzonitic with porphyry texture, extent and types of alteration including potassic, sericitic- potassic, quartz- sericite- carbonate- pyrite, quartz- carbonate- pyrite, silicification- propylitic, propy...

Abstract Amphibole‐rich rocks constitute significant components of the mid‐ to lower continental crust, particularly in active orogens characterized with thick and hot crusts. Nevertheless, experimental data on their viscosity remain scarce. We conducted axial compression deformation experiments synthetic amphibolites under temperature pressure conditions resembling deep sections overthickened ...