An investigation of a Neogene Valley in the Ugra National Park

A paleovalley in the vicinity of the village of Aleksandrovka (Kaluga oblast) has been investigated within the framework of a geophysical survey by Moscow State University for 5 years. A local magnetic anomaly in the region of the paleovalley (a grid of 300 × 1000 m and a scale of 1: 2500) has been confirmed according to the results of electrical-resistivity tomography (ERT) and the spectral induced polarization (IP) method for a series of four profiles. IP measurements at several frequencies have permitted some additional conclusions about the nature of the anomaly. Based on the ERT 2D inversion and IP results, a clear correlation has been revealed between the magnetic anomalies and the high-frequency IP anomalies.