东濮凹陷西南洼沙二下砂泥岩薄互层地震描述技术

The technique of seismic description for Es2x sand-shale interbedded layers in the Southwest Depression of Dongpu Sag

李令喜,苏云,唐娟,肖曾金,刘欣欣,马识途,窦安迪

中国石化中原油田分公司油气勘探管理部，河南 濮阳 457001 中国石化中原油田分公司物探研究院，河南 濮阳 457001

Oil and Gas Exploration Management Department, Zhongyuan Oilfield Company, SINOPEC, Puyang 457001, China Geophysical Research Institute, Zhongyuan Oilfield Company, SINOPEC, Puyang 457001, China

东濮凹陷是一个典型的陆相盐湖断陷盆地，砂泥岩薄互层是常见的沉积叠加样式，同时西南洼地区沙二下储层以浅水三角洲沉积体系为主，单层砂体薄，岩性横向变化快，且受到复杂断裂影响，储层边界刻画不清。为此，提出了一种基于地震相控储层反演技术流程：首先，通过精细岩性标定及井震统计分析，优选反映砂岩厚度的敏感地震属性；然后，运用多属性融合技术刻画地震相，并以地震相进行约束，建立反演低频模型，开展叠后反演；最后，通过坐标旋转与叠前反演技术相结合，实现储层的精细预测。应用结果表明，该技术流程能够有效解决薄储层砂体边界刻画不清以及垂向识别能力不足的问题，可为东部其他区域砂泥岩薄互层地震识别提供借鉴。

Dongpu Sag is a typical continental fault basin of salt lake, the thin sand-shale interbedding is a common style of sedimentary rock stack, and the depositional system of Es2x reservoir is shallow water delta in the Southwest Depression. Owing to the thin single sand body, the drastic lateral variation of lithology and the influence of complex fracture, the characterization of the boundary of reservoir is not clear. Therefore we proposed the inversion technology based on seismic facies: First we choose the sensitive seismic attribute reflecting the thickness of sandstone by fine lithology calibration and well seismic statistical analysis; Second we describe the seismic facies by multi-attributes fusion and establish the low frequency model based on the seismic facies and use the technology of the post-stack seismic inversion to predict the reservoir; Finally, the accurate reservoir prediction can be achieved by combing coordinate rotation and pre-stack seismic inversion. The results of application show that this technology process can effectively solve the problems of blear description of thin sand reservoir boundary and inadequate recognition capability in vertical direction. This technique process can guide the seismic identification of the thin sand-shale interbedding reservoir in the other east areas.

10.6056/dkyqt202104011