The study volcanic complex is located in southern khorasan province, in 90 km of northwest of Birjand and in North of Khour. The study volcanic rocks are including Basaltic andesite andesite and trachyandesite, Latite, Dacite to Rhyodacite and pyroclastic rocks are including Tuff and breccia. The essential and common minerals of these rocks are plagioclase, clinopyroxene, hornblende, biotote and quartz and minor and alteration minerals of these rocks are clay minerals, sericite, calcite, chlorite, epidote and secondary quartz. The majority texture of these rocks is porphyry. Magmatic series of most samples are calc alkaline but some samles have inclination to tholleitic serie. Positive abnormality of Pb is showing alteration of mantle wedge by fluids which have originated from sinking oceanic crust and or from magma contamination with continental crust. Enrichment of samples from Ba and Sr also are related to fluids which are derivated from water bearing sediments and also separation and moving of these fluids from oceanic crust to mantle wedge. Negative abnormality of P, Nb and Ti elements which has caused multiplication pattern in rare elements changing trend in samples, can show formation of rocks in subduction area. Tectonic definition diagrams are showing that andesitic basalts of area are situating in field of calc alkaline basalts of volcanic arc. Furthermore in diagram of magmatic arc definition, the study rocks are situating in field of continental arc and seems which magmatism of area has been result of subduction of a oceanic crust under the continental crust (Lut block).
Gholamreza Fotoohi Rad and Hossein Abbasi niazabadi. Petrology and Geochemistry of Volcanic Rocks in North Khur,
Northwestern Birjand.
DOI: https://doi.org/10.36478/ojesci.2017.10.20
URL: https://www.makhillpublications.co/view-article/1991-7708/ojesci.2017.10.20