大庆长坦以东地区深部与中下部油气封盖条件差异性分析

大庆长坦以东地区是松辽盆地油气勘探的重点地区，登娄库组，泉一、二段和青山口组，嫩一、二段泥岩分别是深部和中下部含油气组合的油气封盖层，由于二者形成于盆地不同的发育阶段，它们的形成环境差异较大，从而使得它们不仅在发育程度上，而且在压力封闭和烃浓度封闭特征上都存在着差异性。深部登娄库组和泉一、二段泥岩除了可对游离相油气形成毛细管封闭外，只部分存在较弱的烃浓度封闭，且单层厚度小，横向分布不稳，只能通过０

ANALYSIS ON DIFFERENT SEALING CONDITION OF THE OIL AND GAS IN DEEP AND MIDDLE~ LOWER PART TO THE EAST OF DAQING PLACANTICLINE

The area to the east of Daqing Placanticline is an important one in exploration of Songliao Basin. The mudstone in Denglouku Formation, Quan I, II Members, Qingshankou Formation and Nen I, II Members is the sealing interval of the hydrocarbon bearing combination in deep and middle lower part. Because this two members forms in different development periods with different environment, so they are different in development maturity, pressure seal and hydrocarbon concentration seal. The mudstone in deep Denglouku Formation and Quan I, II Members contains only partly weak hydrocarbon concentration sealing except forming capillary sealing for free oil and gas. Its single formation has a small thickness and instable lateral distribution, so it can only forms sealing for oil and gas by superimposing. However, the mudstone cap rock of Qingshankou Formation and Nen I, II Members in middle and lower part has the sealing capacity of both capillary and pressure and hydrocarbon concentration. It can form sealing for any phase of oil and gas. As a result, the variety of cap rock condition in deep and middle lower part in this region is an important cause for the difference of the enrichment of oil and gas.