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东海陆架前缘斜坡(冲绳海槽西坡)北部的断块隆脊,是呈长条形的脊状台式隆起,位于29°30′N-31°10′N;128°00′E-128°20′E之间。其由NNE向链状排列的断块山地组成,且与NNE向的断裂构造相一致,其顶部水深约300m～400m左右。从实测单道地震剖面看,隆脊的东西两侧均有断层出现。隆脊西坡倾向陆架一侧,坡度大,有的地方坡度超过10°;而东侧坡度较缓,仅1°左右,缓倾至海槽西坡坡底,并以沟坎式与冲绳海槽槽底相连。冲绳海槽地区的构造运动,使隆脊地区受到断裂构造的作用。NNE向的大断裂使该隆脊位置的东西两侧断裂下降而中间抬起,加之下部岩浆上侵,显现出链式排列的断块山地,表现为一条长形的断块隆脊构造地貌体。推测该地貌体形成的时期较晚,它是与断层的发生同时期形成的
The fault block ridges in the northern part of the East China Sea continental shelf front slope (west slope of the Okinawa Trough) are long ridges with ridge-like ridges that lie 29 ° 30’N-31 ° 10’N; 128 ° 00’E-128 ° 20’E between. It consists of NNE fault-block mountains arranged in the chain, and consistent with the NNE fault structure, the top of the water depth of about 300m ~ 400m or so. From the measured single-channel seismic section, there are faults on both sides of the ridge. On the west side of the ridge, the slope slopes to the side of the shelf, with a large slope. In some places, the slope is over 10 °. On the east side, the slope is gentle, only about 1 °, gently descending to the bottom of the western slope of the trough, Slot bottom connected. The tectonic movement in the Okinawa Trough caused the ridge area to be fractured. NNE-trending fault ruptures the middle and lower parts of the east and west parts of the ridge and intrudes the lower part of the magma, showing a chain-linked fault block mountain with an elongated fault-block ridge topography . It is speculated that the geomorphy body formed later, it is formed at the same time with the occurrence of faults