Types and Distribution of Geological Hazards in the South China Sea

Various types of geological hazards exist in the South China Sea. In dynamics sense, they can be categorized into 5 principal genetic types related to effects of hydraulic dynamics, gaseous activity, soil mechanics, gravity and tectonism, respectively. Integrated analyses indicate that the geological hazards associated with volcanoes, earthquakes and fractures are mainly distributed in tectonically active regions, whereas those resulting from mudflows, landslides and diapirs are usually concentrated in the region of slope, that shallow gas, high pressure gas pockets and soft intercalations are major potential geological hazards in the inner shelf, and that strong hydraulic dynamics, especially storm tide, is one of the major causes of geological hazards in the littoral areas. The geological hazards that occurred in the South China Sea are also characterized by periodicity, succession and, to a certain extent, unpredictability in addition to regionalization.

南海地质灾害类型与分布规律

南海地质灾害用力学观点按其主要成因可划分为5种类型:水动力型地质灾害,气体动力型地质灾害,土力学型地质灾害,重力型地质灾害和内动力型地质灾害。大型地质灾害多发生在构造活动带;滑坡、浊流等主要集中在陆坡地带;内陆架地区浅层气、埋藏河道、古潟湖等比较发育;滨海地区水动力作用,尤其是风暴潮是诱发该区地质灾害的主导因素。南海地质灾害的特点还具有周期性、继承性和新生性。