Mineralogy, geochemistry and petrology of intrusive bodies and volcanic rocks in northwest of Gonabad

The study area is located in Khorasan Razavi Province, NW Gonabad and based on tectonic setting, it is situated in the north of Lut Block zone. Subvolcanic bodies intruded the andesitic lava flows and the pyroclastics rocks. These intrusive bodies consist of small stocks and dykes with composition from quartz diorite, monzodiorite to granite. Widespread alteration identified in southern region that is mainly argillic. Mineralogical composition of this alteration to the abundance is quartz, kaolin, dickite, montmorillonite, hematite and alunite. According to geochemical studies, the granitoids and volcanic rocks are high-K calc-alkaline per-aluminous rocks. REE patterns in all of intrusions rocks show enrichment in LREE (3.5-6.5; ave., 4.75) rather than HREE. Volcanic rocks show high value of LREE/HREE, with LaN/YbN = 3.53 to15.47 and negative Eu anomaly (mean EuN/Eu*= 0.54).