东海北部陆架外缘的边缘沟、坎

MARGINAL GULLY AND SCANP ON THE OUTER CONTINENTAL SHELF MARGIN OF THE EAST CHINA SEA

东海北部陆架外缘向陆坡的转折处，经过历年调查证实，存有一些沟、坎式地形， 它们断断续续地向 ＮＮＥ方向延伸，几乎可以连成一条与陆架外缘坡折线平行的沟和坎。这 些沟、坎式的地貌类型，主要是由于陆架外缘受近代构造运动产生断裂，出现断层，使海底 下落，另外陆架上混浊流也使陆架外缘的沉积物下滑塌落，加上黑潮流的作用而形成。

The analysis of marginal gully and scarp on the north outer margin of continental shelf of the East China Sea north of 29°N and west of 128°20′E shows that they lie on the outer margin of continental shelf and the top of continental slope in water depth from 160 m to 230 m, which can be linked disjointedly to a line. The gully and scarp are about 150 km long, 12-15 m deep and 0. 3- 3. 2 m wide, in trend of NNE. They appear as the natural boundary between continental shelf and continental slope. The sediments near the gully and scarp are heavy coarse sandy materials. In sub- bottom profiles, some shallow faults are found near the continental shelf break, and some slumps and creeps are found in sediment strata, which are closely related to the formation of the marginal gully and scarp on the outer continental shelf margin.