Active Tectonics of the Eastern Arctic: New Data from Geological and Geophysical Studies at Cape Thomas (West of Wrangel Island)

The article presents the results of the first comprehensive geological and geophysical studies of active tectonics in the western part of Wrangel Island, carried out during the expedition of the Northern Fleet and the Russian Geographical Society in 2020. Our research was conducted at Cape Thomas. An active fault at Cape Thomas was identified as an active sublatitudinal fault, along which there had been the repeated movements, thrusting the mountain ridge onto the coastal lowland in the southern direction. In contrast to the Paleozoic‒Mesozoic southward-dipping structures, the active reverse–thrust has the north-dip and reflects displacement of the mountain range from north to south. The studies carried out allow us to reasonably believe that the potential source of strong earthquakes extends along the boundary of the growing tectonic block of the Western Plateau and southern coastal lowland of Wrangel Island. The data significantly refine the dynamics and kinematics of young tectonic movements on Wrangel Island, but are in conflict with low seismic activity. It has been suggested that the potential source is currently in the seismic quiescence stage.