Application of electrical logging methods in exploration of Gulshad polymetallic deposits in Central Kazakhstan

Abstract

Gulshad polymetallic ore deposits are located in the thickness of marbleized limestone and crystalline shale of Silurian age. Ore zones of deposits, confined, as a rule, to tectonic disturbances, have a complex geological structure. The main ore deposits are usually lenticular (often irregular) in shape and are accompanied by smaller bodies located in parallel and in a clump-like manner. The presence of interlayers of carbonaceous shale at the contacts of ore bodies with limestone and in ore intervals is the reason for frequent core drilling in these places. Core recovery from ore intervals in many wells is 30-45%, and in some wells it drops to zero. All this complicates exploration drilling works and makes it difficult to calculate reserves. In 1951-1953, the author tested the possibilities of electrical carotage for determining the thickness of ore bodies and refining geologic sections along drilling profiles.