Identification of Zones of Hydrothermally Altered Rocks Using WorldView-2 Data at the Talman Site (Talmanskaya Area, South-Eastern Transbaikal, Russia)

Abstract

This work is aimed at the practical application of satellite imagery data for the selection of promising areas during geological exploration work in conditions of medium-low mountainous terrain and a sharply continental climate. The processing results and analysis of WorldView-2 data within the Talmanskaya area are presented in order to identify zones of hydrothermal-metasomatic changes in rocks that are promising for identifying of gold-polymetallic mineralization. The choice of the study area is due to sufficient geological knowledge and the absence of man-made formations that affect the result of processing satellite imagery materials. To increase the spectral information content of the WorldView-2 data, the spectral channel ratio method was used, as a result of which a pseudocolor RGB composite was created that displays the spectral characteristics of objects on the Earth’s day surface, in particular, minerals of the oxide/hydroxide group containing transition iron ions (Fe³⁺ and Fe³⁺/Fe²⁺). A comparison of satellite data processing results along with geological information made it possible to identify spectral anomalies as indicators of the presence of near-ore changes, which are an important search criterion for hydrothermal deposits.