A volcano-sedimentary succession, including the Guruf volcanic series, is exposed at Gabal Um in north Eastern Desert of Egypt. series intermediate to silicic flows and associated pyroclastic deposits unconformably overlie quartz-diorite granodiorite plutons are intruded by high-level alkali feldspar granites. The metavolcanic xenoliths shown be unrelated volcanics. Two cycles can recognized. l...

Abstract Hybrid dacite magmas from Taápaca volcano in the Central Andean Volcanic Zone (18°S, northern Chile) contain sanidine crystals of unusual size (1–12 cm) and abundant mafic enclaves variable composition throughout entire eruptive history (1·5 Ma to recent) volcano. They are rich mineral inclusions strongly zoned Ba with distinct growth bands separated by resorption interfaces. Resorptio...

the study area is located at northwest of sarbisheh in south khorasan province and eastern border of lut block. in this area, tertiary (eocene-oligocene to pliocene) volcanic rocks consisting of basaltic andesite, dacite, rhyodacite, vitreous rhyolite (perlitic in some parts), tuff and ignimbrite are exposed. in the daghar mountain, a, b and c perlite layers with thicknesses of 102, 7 and 58 me...

the area is located 20 km northwest of kashmar and about 4 km of kalateh taimour in khorasan razavi province. the study area is part of tertiary volcanic-plutonic belt north of daruneh fault and its situation in tectonic inliers between two important active faults, doruneh and taknar. volcanic rocks are mainly intermediate to acid pyroclastic type. they formed during early tertiary. the volcani...

salafchegan-khorhe volcanic rocks are exposed within urumieh-dokhtar magmatic belt. different kinds of volcanic and subvolcanic rocks of calc-alkaline to alkaline character have been reported throughout this magmatic belt. since, isotopic investigations are very useful for detection of magma petrogenesis and because no isotopic studies have been done in this area, so a geochemical and isotopic ...

Abstract The ~5 km3, 4.54–4.09 Ma Caspana ignimbrite of the Altiplano-Puna volcanic complex (APVC) Central Andes records eruption an andesite and two distinct rhyolitic magmas. It provides a unique opportunity to investigate production silicic magmas in continental arc flare-up, where small volumes magma rarely survive homogenization into regional magmatic system that is dominated by supererupt...

introduction the bornaward area is located in the northeastern iran (in the khorasan razavi province) 28 km northwest of the city of bardaskan at 57˚ 46΄ to 57˚ 52΄ n latitude and 35˚ 21΄ to 35˚ 24΄e longitude. the taknar structural zone, situated in the north central iranian micro continent, is part of the lut block (forster, 1978). the taknar zone is an allochthonous block bounded by the daro...

Data from the U.S. Geological Survey’s National Water Information System (NWIS) database reveal the existence of a number of thermally anomalous areas on the eastern Snake River Plain (ESRP) aquifer, most of them near its margins, and NWIS temperature and chemistry data provided conclusive evidence that thermal waters originating in the hot rhyolitic rocks underlying the ESRP basalts inject hea...