›› 1986, Vol. 6 ›› Issue (4): 346-353.

• 论文 • 上一篇    下一篇



  1. 国家海洋局南海分局
  • 出版日期:1986-10-30 发布日期:1986-10-30


YE Chunchi   

  1. South China Sea Sub-bureau, National Bureau of Oceanography
  • Online:1986-10-30 Published:1986-10-30

摘要: 琼州海峡位于雷琼断陷中部,发育有东西、北西、北东向和南北向四组断裂构造。该区在地质上曾经历复杂的构造运动,自古生代和中生代,主要表现为东西向和东北向构造的迭加和交切。新生代以来,东西向构造在地壳运动中起主要作用,如王五—文教断裂、琼州海峡断裂、和家—前山断裂等具有明显东西走向外,同时还控制了坳陷区和隆起区的形成和发展。近期北西向断裂构造表现最为活跃,如湖仔断裂、沈塘断裂等,北西向断裂不仅部分控制了上第三系—第四系沉积,还成为全新世火山活动的通道。

Abstract: Qiongzhou Strait is one of the largest straits in China. Dominanted by both the EW-trending and NW-trending structural system, the shoreline there is zig-zag in plan shape. Of the sediments on the Strait, sands and gravals, composed of quartz grains and basalt fragments, are distributed on the deep trough where current velocity is relatively high; the finer sediments are accumulated on low-energy areas, such as the bays along coasts and the outer edge of the west mouth of the Strait. A deep trough, 51 km in length and 2.7 km in width, is lying along the bottom of the Strait. On the both sides of the axis of the trough, there is a series of EW-trending depression and eminence features. In the mouths of the Strait, because of the ncreasing of cross-section areas, tidal currents spread and their velocity is reduced. Therefore, two tidal deltas, comprising shoals and troughs which arrange alternatively and radially, are respectively formed in the east mouth and west mouth. On the west delta, the sediments are clayey sands or sandy clays. Contrastly, the sediments on the east delta, being mainly medium or coarse sands, are coarser.