Some regularities of development of relief of mountainous areas and formation of secondary scattering halos

Abstract

One of the most effective methods for ore deposits prospecting is metallometric survey based on the study of secondary scattering halos developed in loose eluvial-deluvial sediments. Metallometric survey is annually used to study significant areas in all ore districts of the country, including Eastern Transbaikalia, where almost all known deposits and ore occurrences are accompanied by secondary scattering halos of various shapes. More often the shape of the halos repeats the outlines of ore bodies, but there are also halos that are strongly elongated down the slope. In this case, the strike of the ore bodies usually does not coincide with the strike of the scattering halos. In some cases, secondary scattering halos are not detected above known, rather rich ore bodies. For example, at one of the tungsten deposits in the Eastern Transbaikalia, rich quartz-wolframite veins confined to the endocontact zone of a small granite massif remained undetected during a detailed metallometric survey. At the same time, much less rich quartz-wolframite veins developed in the exocontact zone of the massif were accompanied by quite clear halos of tungsten scattering. The reasons for this phenomenon were established by analyzing the geomorphological situation of the studied areas of the deposit. It turned out that the nature of secondary scattering halos confined to eluvial-deluvial deposits depends on the conditions of formation of these deposits. The formation of loose eluvial-deluvial deposits is closely related to the process of relief formation of a particular site.