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将研究区线状沙脊群划分为东北区和西南区,东北区沙脊走向约为N116°,该区沙脊线性特征明显,向内陆架延伸收敛,西南区沙脊走向为N120°~N146°,该区沙脊群趋向网状,研究区中部有趋向沙席特征.沙脊群向陆侧发育到60m等深线,东北部向海发育到水深120m左右、西南部发育到150m左右,在西南部洼地130~180m水深处仍有发育不完全沙脊分布.结合靠近研究区的典型地震剖面的沙脊体高角度斜层理声反射特征,以及4个钻孔和12个柱状样岩性分析及测年资料,表明在研究区内广泛分布于东海外陆架的线状沙脊群形成于全新世早中期,并由富含碎贝壳细砂为特征的海侵砂层所组成.沙脊的形成、发育和埋藏的决定因素在于海平面升降导致的水深变化和沉积物源供给速度.12400aBP期M2分潮同潮时线已与研究区线状沙脊群具有较好的正交关系,12000~8000aBP期间的潮波系统可能是形成广泛分布于现东海外陆架线状沙脊群的主动力.
The linear sand ridges in the study area are divided into the northeast area and the southwest area. The trend of sand ridge in the northeast is about N116 °. The linearity of the sand ridges in this area is obvious, extending to the inland shelf. The trend of ridges in the southwest area is N120 ° ~ N146 °, and the sand ridges in this area tend to be reticular, and the sand ridges in the central part of the study area tend to have the characteristics of sand sheets.The sand ridge group develops to the 60 m isobath to the land side, with a depth of about 120 m to the sea in the northeast and about 150 m in the southwestern part , There are still incompletely developed sand ridge distributions in the depth of 130-180 m in the depression of the southwestern China.Based on the high-angle oblique reflection characteristics of the sand body in the typical seismic section close to the study area, and four boreholes and 12 columnar-like rocks The results show that the linear sand ridges distributed widely in the study area on the outer shelf of the East China Sea formed during the early and middle Holocene and are composed of transgressive sand which is characterized by crushed shell and fine sand. The determinant of formation, development and burial of ridges lies in the variation of water depth caused by sea level rise and fall and the deposition rate of sediment source.Meanwhile, the same time tidal line of M2 tide in 12400aBP period has a good orthogonality relationship with the linear sand ridges in the study area , 12000 ~ 8000aBP tidal wave system may be formed during the wide Active force now distributed in East China’s shelf linear sand ridges.