阿尔泰-萨彦山的新构造运动和区域控震断裂的再活化

Neotectonics of the Altai-Sayan Mountains and reactivation of regional faults controlling seismicit

阿尔泰-萨彦山系和新构造结构的形成被认为是印度欧亚板块碰撞带来的远程陆内变形的结果。在本次构造模型中,我们对地质、地震活动数据和地形资料进行了联合分析,认为中亚山带北部地形和地震活动的最大变化仅限于晚古生代区域断层的交叉地带。断层的交叉和接合处应被视为增加基底破碎程度、影响局部应力场变化和预先定位M≥5级的地震震源的最重要的构造因素之一。由此,结合Charysh Terekta和Kurai区域断层交叉带出现的氦和钙华,本次研究获得了发震前兆的一些判断规律。

The formation of mountain system and neotectonic structure of the Altai-Sayan region is regarded to be a result of intercontinental deformations,related to a distant effects of tectonic stress from the Indo-Eurasian collision.Within this tectonic model we carried out the joint analysis of the geology,seismicity data and topographic materials enable to assume that the maximum changes in the relief and seismic activity in the northern part of Central Asia mountain belt are confined to the zones of intersections of the Late Paleozoic regional faults.The intersections and junctions of faults should be considered as one of the most important structural factors that increase the fragmentation of the substrate,affect changes in the local stress field and predetermine the localization of large earthquake foci with a magnitude M≥5.Some regularities were revealed,based on the example of helium and travertine manifestations in the junction zone of the Charysh-Terekta and Kurai regional faults,which can be used as precursors of earthquakes.