Seismotectonic model of the Aldan-Stanovoy shield (Easten Siberia)

Abstract

The Aldan-Stanovoy Shield is located in the south-eastern Siberian platform. The territory is marked by a high seismic activity. The earthquake epicenters are mainly clustered at the Aldan and Stanovoy megablock boundary forming the Olekma-Stanovoy zone of the Baikal-Okhotsk seismic belt. Seismicity of the Olekma-Stanovoy zone is considered in the context of a block structure and a three-layer model for the crustal structure of the Aldan-Stanovoy Shield. The main geodynamic factor of seismicity is the interaction between the Euro-Asia and Amur lithospheric plates and density domains of the Earth's crust upper part such as large massifs of granite, anorthosite and granite-gneiss domes. The hypocenters are mostly consentrated in the intermediate crustal layer at the depth of 12 to 30 km. Strong earthquakes ($M>5$) usual are clustered to the south part of the Chara-Olekma, Central-Aldan, Timpton-Uchur and Batomga blocks in the upper part of the granite-gneiss domes.