Active Faults and Large Paleoearthquakes of the Sayan-Tuva Upland
摘要
This paper presents an overview of seismogeologic studies of the Sayan-Tuva Upland. It gives an idea of the stages of activation of neotectonic movements and fault block structure. The main element in the neotectonic plan of the highland is the Sayan–Tuva geoblock. It has an ellipsoidal shape in plan and is bounded by deep faults: Shapshal in the west, Sayan-Minusa in the north, Main Sayan in the east and Bolnay in the south. The internal structure of the block is a system of sub-latitudinal or northeast-trending faults. The structure is formed under conditions of compression due to the remote impact of the Indo-Asian collision. Under these conditions, the accumulated stresses are realized in the form of rapid movements along the faults, generating seismicity. Strong earthquakes leave a system of deformations that can be easily recognized in the morphology and on satellite images. This makes it possible to identify the epicenters of strong paleo-earthquakes and to study them in detail. The application of paleoseismogeological, morphometric and geochronological methods has opened up new possibilities for the determination of paleoearthquake magnitudes, slip rates and recurrence periods, which are the basis for seismic zoning of territories.