青藏高原东缘活动断裂地质灾害效应研究

活动断裂的地质灾害效应是工程地质与地质灾害领域研究的重要内容。本文以第四纪以来构造活动最强烈的青藏高原东缘为例,阐述了活动断裂地质灾害效应的主要表现形式,包括:(1)活动断裂对地形地貌和岩体结构的影响;(2)断裂剧烈活动(地震)诱发地质灾害;(3)断裂蠕滑作用对斜坡应力场和稳定性的影响;(4)断裂活动是地质灾害链的源头,为地质灾害提供物源。上述表现形式及灾害成因机理和分布规律是活动构造区地质灾害防治中需要关注的关键问题。根据青藏高原东缘典型地质灾害案例研究提出,内外动力耦合作用成灾机理是未来地质灾害研究方向,将为活动构造区地质灾害早期识别和防灾减灾提供理论依据。

Research on the Geohazard Effect of Active Fault on the Eastern Margin of the Tibetan Plateau

The geohazard effect of active fault is one of the important subjects of engineering geology and geohazard research. Exemplified by the east margin of the Tibetan Plateau characterized by the most intense tectonic activities since Quaternary, this paper has presented major manifestations of the geohazard effects of active faults, which include (1) influence of active faults on terrain landforms and rock mass structure, (2) dramatic activities of a certain fault (earthquake) inducing geohazards, (3) influence of fault creep slipping on slope stress field and slope stability, (4) fault activity acting as the source of geohazard chain, which can provide abundant materials for landslides or debris flows. These manifestations, together with the geohazard formation mechanisms and their distribution regularity, are key problems which should be emphasized during geohazard prevention. Based on typical geohazard cases on the eastern margin of the Tibetan Plateau, the authors point out that the coupling mechanism of endogenic and exogenic geological processes is the research direction of geohazards in the future, which can provide important theoretical basis for early recognition and prevention of geohazards in the tectonic active regions.