Evaluation of element mass changes according to Grant- Gresens equations and Isocon method in Kervian shear zone gold mineralization

Document Type : Research Paper

Authors

Abstract

Based on studies, Kervian gold mineralization is known as the shear zone type. Gold mineralization in this area has been controlled by factors such as plastic shear zones and hydrothermal alteration. Dominant alterations are chloritic and sericitic, and in some places silicic and carbonatic alteration are seen. Hence, geochemical comparison of non-altered rocks with altered rocks in the region will help to evaluate the effects of alteration process on the element scattering and investigate geochemical behavior of elements. Geochemical behavior (kind and rates of mobility) can be defined as a quantitative measure to evaluation of mineralization area. Isocon method is defined based on process where the immobile variables identified, and according that element by loss and gain behavior is separated. Numerical calculations were carried out to recognize mobile or immobile elements in various rock units (Intrusive rocks, metavolcanic and shear zone) and also different ratios of these elements in altered and non-altered area showed that elements of Al, Ti, and rarely Na, Cr having immobile behavior, and their masses was relatively unchanged during alteration. As, La, Mo, Ba, Mn and Au was added and As in shear zone part showed maximum mass gain. Also Zn, Ca, Sr and Mg were depleted in all kind of rocks. Exploration ratio which show distal and proximal to mineralization area, constructed from the total abundances of added element to depleted element, and according this survey exploration index is defined.

Keywords