东海和凯尔特海潮流沙脊的对比研究

A Comparative Study on Tidal Sand Ridges in the East China Sea and Celtic Sea

东海潮流沙脊与凯尔特海沙脊均为开阔陆架上的大型深水沙脊,它们都形成在冰后期海面上升时期。目前仍然经受现代潮流和风暴浪的作用,具有一定的活动性,处于活动沙脊和衰亡沙脊之间的发育过程,属于准活动沙脊。与东海比较,凯尔特海的动力作用更强。东海沙脊横剖面大多呈向西南方向倾斜的前积层理,偶见波浪侵蚀面,反映以潮流作用为主形成的沙脊内部结构的特点;凯尔特海沙脊剖面呈现复杂的交错层理,内部有较多的波浪侵蚀面,这是潮流和波浪共同作用形成的沙脊内部结构的特点。

The tidal sand ridges in the East China Sea and the sand ridges in the Celtic Sea are all large-scale and deep water sand ridegs on open continental shelf, and were formed in the postglacial sea level rise period. They are still affected by the modern tidal current and storm wave, are in a developmental process between active and moribund sand ridges and belong to quasi-active sand ridges. The dynamic effects in the Celtic Sea are stronger than those in the East China Sea.On the seismic profiles of sand ridges in the East China Sea, the foreset beddings incline mostly to the southwest and the wave eroded surfaces were occasionally seen, which reflect the internal structure characteristics of tide-dominated sand ridges; on the seismic profiles of sand ridges in the Celtic Sea, there are many complex cross beddings and wave eroded surfaces, which are typical internal structure characteristics of sand ridges formed by the joint actions of tidal current and wave.