通过对渤海东部CD5孔岩性、生物以及年代学的地层分析,晚第四纪以来划分出2个陆相和2个海相层,两次海侵的时间段分别为39-22和9kaBP至今。CD5钻孔附近渤海潮流三角洲大约在3600-2400aBP以来开始快速沉积,形成了4.8m厚的潮流沙席,结合渤海中东部10多个钻孔资料,总结了潮流沙席的环境演变过程,自全新世海侵以来可以大致分为9~8、8~3.6~2.4、3.6~2.4kaBP以来3个阶段,而目前正处于相对稳定状态。
According to analysis of lithology, biology and chronology, hole CD5 can be identified to have two marine beds and two continental beds from top to bottom. The two transgressive periods were from 39 to 22 kaBP and from 9 kaBP to the preseal day. Tidal delta of the Bohai Sea around hole CD5 has had rapid sedimentation since 3600-2400 kaBP and formed tidal sand sheet 4.8 m in thickness . Through analyzing more than 10 holes in the east Bohai Sea, the environmental evolution of ridal sand sheet from Holocene was clear and the sand sheet experienced three evolution stages(9-8 kaBP,8-3.6 kaBP,3.6-2.4 kaBP), and now it is relatively stable.