Abstract:
The carbonaceous black-shale strata of various ages that exist in different regions of the earth sometimes host large ore bodies, and are the subject of intense scrutiny. The widespread occurrence of black shales in Mongolia and of sulfidized rocks with organic matter in them was proved in recent years as a byproduct of studies on the composition of ophiolites and metasedimentary rocks. One region with such rocks occurs west of L. Hoebsoegoel in northern Mongolia. The authors mapped black shales in an area bounded to the south by the Shishhid Goel River, and to the north and west by the USSR-Mongolia boundary. They found sulfidized rocks with organic matter among the sedimentary-metamorphic formations at two stratigraphic levels. The high content of sulfides in the black shales west of Lake Hoebsoegoel makes this region promising for the discovery of some commercially valuable minerals and calls for organization of large-scale exploration.