The Neotectonic Structure of Deception Island (Antarctica) Inferred from the Results of Structural and Geomorphic Analysis

We present the results of analysis of the Strombolian-type Deception volcano after its explosive caldera-forming eruption. The volcano studied, located in the South Shetland Archipelago (Antarctica), was selected in accordance with the “Strategy for the Development of the Russian Federation Activities in Antarctica for the Period until 2020 and for the Long-term Period until 2030.” On the basis of original structural–geomorphic constructions and literature data, the location of volcano is substantiated, the modern tectonic structure of volcano is revealed, and the influence of geodynamic settings in adjacent regions on the evolution of the volcano is assessed. We applied the structural–geomorphic method, which is developed by the national scientific school and successfully tested in practice. The initial materials were topographic and bathymetric maps of various scales, satellite and ground-penetrating-radar images, the digital elevation model compiled, and published geophysical and geological information. It is concluded that Deception volcano was formed at the intercept between the large Hero Fracture Zone and the regional fault framing the South Shetland Archipelago from its southeast, without the influence of the geodynamic regime of the adjacent Bransfield rift, which is considered by a number of researchers to play a leading role in the evolution of the volcano. The modern volcano structure is characterized by fault-block tectonics with the domination of NE-trending faults.