泌阳凹陷南部陡坡带核桃园组二段砂砾岩体发育的控制因素分析

Analysis on Controlling Factors of the Glutenite Body Development in Eh2 of Southern Steep Slope of the Biyang Depression

根据古构造地貌特征和现今构造格局,将泌阳凹陷划分为三个带:南部陡坡带、中部深凹带和北部斜坡带。长期以来,泌阳凹陷油气勘探的重点一直集中在核桃园组三段,认为核桃园组二段(下简称核二段)生油能力不足。随着油田勘探程度的提高和相关理论研究的深入,特别是对低熟、未熟油成藏理论和下生上储成藏规模量化研究的突破,奠定了在泌阳凹陷核二段找油的基础。经综合研究认为,在核二段沉积时期南部陡坡带砂砾岩体发育受控于边界断裂、古地貌、物源、水动力及古气候等因素,其中断裂的活动强度及古地貌为主控因素。通过研究砂砾岩体发育及不同规模砂砾岩体分布与主要控制因素间的关系,建立了南部陡坡带核二段的控砂模式图。

According to characteristics of ancient tectonic landform and present tectonic framework,Biyang depression can be divided into three zones,Southern steep slope,Middle deep depression and Northern slope regions.For a long time oil-gas exploration of Biyang depression focuses on Eh3,and oil-producing ability of Eh2 is regarded inadequate.Along with improvement of exploration degree and intensive study of relative theory,especially the breakup of reservoir-forming theory of immature and low mature oil and quantitative investigation of lower generating and upper reservoiring formation scale,foundation of seeking oil and gas in Eh2 were established.Comprehensive study shows that during the sedimentary period of Eh2 glutenite body development in southern steep slope zone was controlled by the boundary fracture,palaeogeomorphology,material sources,hydrodynamic force and paleoclimate and other factors,among which the intensity of fracture activities and palaeogeomorphology were the dominant ones.After research on sandbody development and the relations between the distribution of various scale sandbody and main controlling factors,the sandbody-controlled model of Eh2 in southern steep slope zone was set up.