A study of five diamonds containing mineral and fluid inclusions, selected among forty-nine specimens from the Cullinan Mine, South Africa, was carried out to better document origin formation N-absent B-poor (type IIb) diamonds. The combination several in-situ non-destructive techniques used identify mineralogy chemical composition primary secondary inclusions. These include breyite, larnite, g...

Abstract The scarcity of historical rhyolite eruptions means that volcanological and petrological studies past are a key tool for assessing the potential future hazardous activity improving interpretations unrest signals. For last 18 ky, Laguna del Maule (LdM) volcanic complex in Chile has erupted primarily rhyolites but with differing magma compositions, eruption styles eruptive volumes. Rapid...

introduction the area studied is located north of azna (lorestan province) in a small portion of the sanandaj – sirjan structural zone (mohajjel et al., 2003).this area is part of the zagros orogenic belt, formed by the opening and closure of neotethyan ocean. from ne to sw, it consists of three parallel tectonic regions: the orumieh-dokhtar magmatic belt, the sanandaj-sirjan structural zone an...

The Susong metamorphic complex (SSC) in the southern margin of Dabie orogenic belt (DOB) central-eastern China is a key unit for understanding subduction and exhumation processes DOB. However, formation age grade SSC remain uncertain, hampering our mechanism An integrated study field survey, regional petrology, geothermobarometry, U–Pb dating zircon was carried out this study. Our results revea...

The composite Albian–Eocene orogenic wedge of the northern part Inner Western Carpathians (IWC) comprises European Variscan basement with Upper Carboniferous–Triassic cover and Jurassic to Cretaceous sedimentary successions a large oceanic–continental Atlantic (Alpine) Tethys basin system. This paper presents an updated evolutionary model for principal structural units (i.e., Fatricum, Tatricum...

Abstract The reliability of eight Fe–Mg exchange geothermobarometers for garnet-bearing peridotites, pyroxenites and eclogites has been examined using a database comprised more than 300 published peridotite, pyroxenite eclogite experiments conducted from 10 to 70 kbar 850 &gt; 1650 $$^\circ{\rm C}$$ <mm...

introduction volcanic rocks with a porphyritic texture have experienced two crystallization stages. the first is slow, resulting in phenocrysts, and the second, which took place at, or near the surface, or during intrusion into a cooler body of rock, result in a groundmass of glass, or fine crystals. the pressure and temperature history of a magma during crystallization is recorded in the chemi...

This project examines a sequence of Tertiary volcanic rocks from the Langidalsfjall mountain range in the Skagi Peninsula of north-central Iceland, formed at about 7-8 Ma. This sequence is composed of basaltic flows, andesitic flows, and rhyolitic rocks (a flow and a dike). The main unit of interest is a 30-40 m thick plagioclase-phyric andesite flow. This flow contains calciumrich (up to An88)...