塔中地区上奥陶统礁滩复合体储层地震预测技术

塔中Ⅰ号坡折带位于塔中古隆起北斜坡大型碳酸盐岩台地北缘,呈北西-南东走向,台缘坡折带长220 km,宽8～18 km,发育上奥陶统大型礁滩复合体,油气藏埋深3 700～7 200 m.该带地表沙丘起伏,地下结构复杂,地震剖面品质差,奥陶系碳酸盐岩储层埋深大,非均质性强,储层控制因素复杂.通过地质、测井、岩心和试油等资料分析了奥陶系礁滩体不同类型储层的地球物理响应特征,总结出适合于该带碳酸盐岩礁滩体储层预测的方法,对上奥陶统礁滩复合体发育分布规律进行了精细描述,在礁滩体复合体的勘探中取得了很好的勘探成果.

Seismic reservoir prediction of reef flat complexes in the Upper Ordovician,Tazhong area

Tazhong-Ⅰ slopebreak zone is located at the north margin of the large carbonate platform developed on the northern slope of Tazhong paleo-uplift.The northwest trending slope break is 220 km long and 8-18 km wide.It developed large reef-flat complexes in the Upper Ordovician and harbors giant condensate gas reservoirs with burial depth of 3 700-7 200 m.High-quality seismic profiles are hard to acquire here because of the undulate dunes at the surface and complex structures underground.And the accuracy of lateral reservoir prediction is low due to the deep burial depth of the Ordovician carbonate reservoirs,high heterogenity,and multiple controlling factors upon reservoir development.However,a set of methods have been developed and applied successfully to the prediction of the reef-flat carbonate reservoirs through analyzing geophysical responses to various types of Ordovician reef-shoal complex reservoirs based on geologic log,core,and test data.The application of these methods has accelerated the exploration of large condensate gas reservoirs in the slope break zone.