摘要
Abstract
Seismic activities, especially modern large earthquakes along fault zones have long been a key issue in research of active tectonic. With increasing study in this field, the research target currently focuses on large earthquakes occurring in both spaces consisting of several faulting zones and faulting blocks rather than in one faulting zone. After the Wenchuan and Yushu earthquakes, activities of the Bayankala faulting block have attracted extensive concern. Based on overall movement of the Bayankala faulting block, and combined with all the historical record of large earthquakes (Ms≥7) occurring in each faulting zone since 1900 and analysis of modern seismic activities, this study analyzed these seismic activities and their quasi-periods, focal mechanism, maximum magnitudes, and the relationship between strike-slip faults in boundaries and large earthquakes. The main understanding in this study is as follows. ①There were three earthquake series since 1900: the Diexi-Huashixia earthquake series ( 1923 ～ 1937), the Dari-Luhuo earthquake series (1947 ～1976) and the Kunlun-Wenchuan earthquake series (since 1997). ② There are big differences in the time interval of two series and the duration time of each earthquake, a bigger difference occurs in the Dari-Luhuo series and the other two series, and the Kunlun-Wenchuan series is not over yet. ③ After the Kunlunshan Ms8. 1 earthquake and Wenchuan Ms8. 0 earthquake, the Kunlun-Wenchuan series is not over yet and big earthquakes are very likely to happen. Although the Bayankala faulting block has released most energy, within the time scope of earthquake series, the magnitudes of earthquakes after release of a large amount of energy are likely lower than that of earthquakes following release of a small amount of energy.④ Strike-slip faults are the major boundary faults which controlled the movement of Bayankala fault-block, forming the major part of each series.⑤ Strong northward extrusion of Indian plate is the most vital condition for earthquakes from formation to development and finally to occurrence in these boundary faults.关键词
青藏高原/巴颜喀喇断块/走滑断裂/地震系列Key words
Tibetan plateau/ Bayankala fault-block/ strike-slip fault/ earthquake series 
