辽河断陷东部凹陷中段沙河街组砂岩储集体预测

Sandy Reservoir Prediction of the Shahejie Formation in Central East Depression,Liaohe Basin

本文针对东部凹陷中段砂岩储集体分布规律不清等问题 ,开展了以层序地层学为指导的砂岩储集体预测工作。通过对目标层序地震、钻井及岩心等资料的成因地层分析 ,发现同沉积断裂、古地貌及岩浆活动控制了砂岩储集体的展布。同沉积断裂的活动加大了碎屑岩在断层下降盘沉积的可容纳空间 ,为河流相砂岩储集体的发育提供了场所 ;岩浆活动形成的火山岩堆积体则占据了碎屑岩沉积的可容纳空间 ,导致火山岩堆积体之上仅发育以泥质为主的堤岸、溢岸沉积。在此地貌背景控制下 ,河流相砂岩沿火山岩堆积体侧翼的断槽一带展布。本次研究为砂岩油气藏勘探指明了方向 。

It is necessary to do further research work on the prediction of the sandy reservoirs distributed in areas of insufficient core data. Aiming at solving the problem that the sand reservoirs were poorly developed in the target area of Central East Depression within Liaohe Basin, the authors carried out the research based on the sequence stratigraphy for the purpose of predicting the distribution of SQ2 TST sand bodies. The sand bodies in SQ2 TST are governed by paleotopography. The growth of faults and volcanic hills were studied comprehensively according to the data of 3-D seismography, wells and cores. It is shown that the accommodation space was remarkably expanded by the faulting activities, and the channel sand bodies were well developed along the surface of the sequence boundary during the rising cycle of the base level. However, the volcanic hills occupied the accommodation space of channel sediments. Therefore, the overbank flowing sediments were chiefly developed on the highs, while the channel sand bodies were distributed mainly along the lows. On the basis of the above discussions,the distribution of channel sand bodies was discovered, and the drilling engineering designed along the channels has been proved to be successful.