Petrology, Magnetic susceptibility, Tectonic setting and mineralization associated with Plutonic and Volcanic Rocks, Eastern Bajestan and Taherabad, Iran

زمین شناسی اقتصادی

Article 4, Volume 1, Issue 1, January 2010, Pages 83-100   

Document Type: Research Article

DOI: 10.22067/econg.v1i1.3674

Authors

Maliheh Ghoorchi Rooki^{* 1}; Saeed Saadat²; Ali Reza Ashouri¹

¹Ferdowsi University of Mashhad

²Mashhad Branch, Islamic Azad University

Abstract

Study area is located in district of Bajestan and Ferdows cities, NE of Iran. Structurally, this area is part of Lut block. The oldest exposed rocks, to the north of intrusive rocks and in Eastern Bajestan, are meta-chert, slate, quartzite, thin-bedded crystalline limestone and meta-argillite. The sedimentary units are: Sardar Formation (Carboniferous), Jamal Formation (Permian), Sorkh Shale and Shotori Formations (Triassic), carbonateous rocks (Cretaceous) and lithostratigraphically equivalent to Kerman conglomerate (Cretaceous-Paleocene) are exposed in this area. Based on relative age, magmatism in eastern Bajestan and Taherabad started after Late Cretaceous and it has been active and repeated during Tertiary time. At least, three episodes of volcanic activities are recognized in this area. The first stage was mainly volcanic flow with mafic composition and minor intermediate. The second episode was mainly intermediate in composition. The third stage was changed to acid-intermediate in composition. Since the plutonic rocks intruded the volcanic rocks, therefore they may be Oligo-Miocene age. Bajestan intrusive rocks are granite-granodiorite-quartz monzonite. Taherabad intrusive rocks are diorite-quartz diorite- monzonite-latite. Bajestan intrusive rocks are reduced type (ilmenite series) and Taherabad intrusive rocks are oxidized type (magnetite series).Based on geochemical analysis including trace elements, REE and isotopic data, Bajestan intrusive rocks formed in continental collision zone and the magma has crustal origin. Taherabad intrusive rocks were formed in subduction zone and magma originated from oceanic crust. Taherabad intrusive rock has exploration potential for Cu-Au and pb.

Keywords

Petrology; mineralization; Tahetabad; Bajestan