南海北部海底沙波研究

南海北部水深100~250 m的陆架和陆坡斜坡海底分布着大片沙波地貌,本文采用底形相图参数近似计算和泥沙起动流速2种计算方法,结合海底微地貌的实际形态,研究了沙波的沉积特征及其成因机理。研究认为,区内的沙波为现代沉积地貌;控制沙波形成发育的主要水动力因素是潮流与风暴条件下风海流的叠加;区内泥沙颗粒粒径适宜,海底坡度平缓,有利于海底沙波的发育。

Study on the Seafloor Sandwaves in the Northern South China Sea

A large area of sandwave geomorphology has been found on the seafloor of the outer continental shelf and upper slope at a water depth of 100--250 meters in the northern South China Sea, Approximate calculation for bedform stability parameters and incipient motion of sediment combined with the actual configuration of seafloor microtopography are adopted to study the sedimentation characteristics and the cause and mechanism of its formation. The results indicate that sandwaves belong to modern sedimentation geomorphology; the primarily hydrodynamic factor of sandwave formation is dominated by nestification of tidal currents and wind currents generated by storm tide; the appropriate sediment size and gentle seafloor gradient is in favor of the growth of the seafloor sandwaves.