东营凹陷西部潜山油气藏特征

东营凹陷西部发育太古界、古生界及中生界潜山。受郯庐断裂活动的影响,潜山在平面上呈带状分布,自东南向北西形成了NW-向潜山构造带;自西南向北东形成了NE向潜山构造带。新生界的沙河街组、孔店组及中生界和古生界的石炭二叠系的烃源岩为潜山油气藏的主要油源。储集层由太古界变质岩和下古生界碳酸盐岩组成,平均孔隙度多在1.4%～5.0%之间。石炭-二叠系、第三系及中生界下侏罗统构成潜山油气藏的3套盖层。根据圈闭类型的差异,潜山油气藏分为潜山顶部及内幕两种类型。烃类潜山油气藏多分布于近源的断裂带附近,而非烃气往往沿深大断裂、火山通道向上运移,在适当的潜山圈闭中形成非烃潜山气藏。

POOL FEATURES OF BURIED HILL IN WEST PART OF DONGYING DEPRESSION

Buried hills of Archaeozoic,Paleozoic and Mesozoic Eras developed well in the west part of Dongying Depression. Affected by Tanlu fault activities, the buried hills took the form of zonal distribulion,thus forming NW and NE strike buried hill structural zones. The Cenozoic Shahejie and Kongdian Formations, the Mesozioc and the Permo Carboniferous Systems are the main source rocks of the buried hill oil pools. The reservoir rocks are Archaeozoic metamorphic rocks and Lower Paleozoic carbonate rocks. The cap rocks are the strata of Permo Carboniferous, Tertiary and Lower Jurassic. The pools could be divided into hill top type and inside hill type.Hydrocarbon pools are basically distributed close to fractural belts near source rocks, and non hydrocarbon gases usually migrated along deep rift,the pathways in volcano to form non hydrocarbon gas pools in proper buried hill traps.