Volcanism is a substantial process during crustal growth on planetary bodies and well documented to have occurred in the early Solar System from the recognition of numerous basaltic meteorites. Considering the ureilite parent body (UPB), the compositions of magmas that formed a potential UPB crust and were complementary to the ultramafic ureilite mantle rocks are poorly constrained. Among the A...

Introduction: Geomorphological observations of Mars surface and mineral detection, in particular hydrated sulphates, militate for the idea that liquid water have existed on Mars surface, even if physical conditions forbid its presence today. Beside the sul-phate formation which requires particular chemical conditions, clay minerals are of particular interest because they are the first by-produc...

kalchoye copper-gold deposit is located about 110 kilometers east of esfahan province and within the eocene volcano sedimentary rocks. sandy tuff and andesite lava are important members of this complex.the form of mineralization in area is vein and veinlet and quartz as the main gangue phase. the main ore minerals are chalcopyrite, chalcocite, galena and weathered minerals such as goethite, iro...

On many volcanoes, there is evidence of a relationship between dome collapse and periods of high precipitation. We propose a mechanism for this relationship and investigate the conditions that optimize failure by this process. Observations of elongate lobes that evolve through exogenous growth of lava domes reveal that they commonly develop tensile fractures perpendicular to the direction of mo...

Abstract Recognition of any intra-oceanic arc-trench system (IOAS) could provide invaluable information on the tectonic framework and geodynamic evolution vanished ocean basin. The Tanjianshan Complex mafic-ultramafic rocks along North Qaidam ultra-high pressure metamorphic belt in NW China record subduction process Proto-Tethyan Ocean. Four lithotectonic units, including island arc, ophiolite,...

neyshabour turquoise mine is located in northwest of neyshabour, southern quchan volcanic belt. eocene andesite and dacite forming as lava and pyroclastic rocks cover most of the area. subvolcanic diorite to syenite porphyry (granitoids of magnetite series) intruded the volcanic rocks. both volcanic and subvolcanic rocks are highly altered. four types of alteration are recognized including: sil...

introduction in the east and northeast of sanandaj in the qorveh-bijar-takab axis, there are series of basaltic composition volcanoes with quaternary age. the study area is part of the sanandaj-sirjan zone and is located between 47°52' and 47°57' e longitudes and 35°26 and '35°30' n latitudes. due to the location of the volcanic cone on pliocene clastic sediments and quaternary travertine, the ...

a r t i c l e i n f o Keywords: silica-undersaturated volcanism 238 U-230 Th-226 Ra-210 Pb series disequilibria magma transport and residence time carbonate metasomatism volcanic hazard assessment The silica-undersaturated Nyiragongo volcanics, located in the East African Rift, have globally unique chemical compositions and unusually low viscosities, only higher than carbonatite lavas, for terr...