东三江盆地南部白垩纪以来的沉积特征及其演化

东三江地区白垩纪以来的沉积特征及其演化，对大庆外围地区的油气勘探和揭示东北亚地区演化机制具有重要意义。根据岩心、录井、测井以及地震等资料的详细研究表明：白垩纪以来均发育扇三角洲-湖泊沉积体系。早白垩世为弧后伸展型盆地，残留地层中有滨浅湖和火山岩沉积；晚白垩世为北东向展布的板内挠曲挤压型盆地，发育以盆地两侧绥滨和完达山为物质供给的短轴物源，海浪组－七星河组发育逆同生断层，半深湖的面积先扩大后缩小，雁窝组以盆地充填消亡为主。新生代为右旋走滑拉分盆地，以继承性的短轴物源为主。在宝泉岭组时期有桦南隆起方向的长轴物源，宝泉岭组－富锦组下、中段，半深湖面积扩大，沉积中心向东南迁移；富锦组上段，水体变浅，湖盆面积扩大，沉积中心向西北迁移。

Sedimentation Features and Its Evolution Since Cretaceous in the South of Eastern Sanjiang Basin

The sedimentation features and its evolution since Cretaceous in the eastern Sanjiang basin play an important role for the oil and gas exploration in the outer Daqing area and also are essential for the research of evolution in NE Asia.Detailed studies on the rock cores,geo-loggings,well loggings,and seismic materials show that,fan delta and lake sediment system developed since Cretaceous.In the Early Cretaceous,it was a spreading back-arc basin,some shore-shallow lake and volcanic sediments developed in the residual stratums;in the Late Cretaceous,it was a NE displayed intra-plate flexure-squeezed basin with short axis sediment sources from the Suibin and Wandashan on the both sides of basin,conversed contemporary fault developed in the Hailang-Qixinghe Formation,area of the semi-deep lake shrinked after extension,followed by basin filling and disappearing in the Yanwo Formation.In the Cenozoic,this basin was a dextral strike-slip pull-apart basin with the main sediments from an inherited short-axis source.During Baoquanling period,a long-axis sediment source appeared in the direction of Huanan uplift.From Baoquanling to the Lower-Mid period of Fujin,the semi-deep lake area extended with the sedimentation center moving towards southeast.During the Late Fujin period,the water body became shallow and the basin extended with the sedimentation center moving northwestward.