northwest of shir-kuh batholith, a number of leucocratic granitic and granodioritic plutons have intruded sedimentary hosts including shale-sandstone (triassic-jurassic) and sandstone-conglomerate (lower cretaceous). contact metamorphism and hydrothermal alterations are widespread. late alteration assemblage mainly occurs in arkosic sandstones of sangestan formation and includes propylitic, qua...

The study area is located ~50 km in the north of Tehran capital city, Iran, and is a part of central Alborz Mountain. The intrusive bodies aged post Eocene have intruded in the Eocene volcanic units causing hydrothermal alterations in these units. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) images were used to map hydrothermal alteration zones. The propylitic, phyllic...

Tourmalinization characterizes the most pervasive alteration type in the Nezam Abad ore deposit, west-central Iran. It delineates high-temperature centers of mineralization and together with quartz and cassiterite form inner parts of the alteration halo. The composition of tourmalines plots mostly along and between the proton and alkali-deficient end members. Tourmaline in quartzdioritic host i...