|
ASSESSMENT OF POTENTIAL TSUNAMI GENERATION IN CHINA'S BOHAI SEA FROM DIRECT GEOTECTONIC AND COLLATERAL SOURCE MECHANISMSKeywords: Bohai Sea , tsunami , tsunami hazards , tsunami risks , earthquakes , gas hydrates , tsunami generation Abstract: The Bohai Sea borders northeastern China's most populous and highest economic valuecoastal areas where several megacities are located. Critical infrastructure facilities exist or areunder construction, including a nuclear power plant and super port facilities. Large reserves of oilhave been discovered and a number of offshore oil platforms have been built. The extent ofdevelopment along coastal areas requires a better assessment of potential tsunami risks. Althoughtsunamis do not pose as much of a threat as earthquakes in this region, locally destructive tsunamishave been generated in the past and future events could have significant impacts on coastalpopulations and China's economy, particularly because most of the development has taken place inlow-lying regions, including river deltas. The present study examines the geotectonics of the Bohaibasin region, the impact of past historical events, and the potential for local tsunami generationfrom a variety of direct and collateral source mechanisms triggered by intra plate earthquakes.More specifically, the present study examines: a)major active faults bounding the Bohai Basin; b)the resulting crustal deformation patterns of tectonic structures that have resulted in catastrophicearthquakes in recent years; c) the basin-wide extension - with local inversion - extending into theBohai Sea that generated tsunamigenic earthquakes in 1888 and 1969; and d) deformational futureseismic events with the potential to generate local tsunamis directly or by collateral mechanisms offolding, en-echelon bookshelf failures, or from destabilization/dissociation of structuralaccumulations of gas hydrate deposits within the basin's thick sedimentary stratigraphic layers.
|