The results of application of the VES-IP method during the study of sand–gravel mixes in Mosalsk district, Kaluga oblast

Abstract

Vertical electrical sounding (VES) is a traditional method of exploration of sand–gravel mix (SGM) deposits. Geophysicists are challenged not only to determine the boundaries of SGM deposits, but also to determine their basic properties, for example, to locate the zones with high gravel contents within SGM deposits or determine the content of clay particles in sands. In order to meet these challenges, it is necessary to use new methods, in particular, the method of induced polarization (IP). This paper presents the results of direct-current VES-IP surveys that were carried out in the territory of Mosalsk district, Kaluga oblast, in 2015. The measurements were made at both known SGM deposits that are under development and new areas under prospecting where drilling has not been performed as yet. The study results show that all SGM deposits are characterized by high values of induced polarization. The complex adjustment of the apparent resistivity and apparent polarizability curves significantly confine the limits of equivalent models when interpreting the data in complex geological situations when sand-and-gravel deposits weakly differ from the host rocks or are superimposed with a thick layer of conducting clay loams.