基于层面的地震曲率属性在碳酸盐岩断裂预测中的应用——以塔里木盆地塔北某区块为例

Application of seismic curvature based on horizon to carbonate fault prediction:An example of an area in Tabei,Tarim Basin

塔里木盆地塔北某区块奥陶系碳酸盐岩地质年代老,地层埋深大,原生基质孔隙发育较差,其储层的有利分布区多受断裂控制。因此,对该区断裂进行精细预测显得尤为重要。针对断裂精细预测难度较大这一实际问题,选用近年来颇受关注的地震曲率技术,运用曲率原理和基于层面的地震曲率属性对研究区奥陶系一间房组顶界进行断裂预测,从常用的几种地震曲率中优选出最小负曲率和最大正曲率对断裂进行刻画,取得了较好的应用效果。通过地震剖面和基于层面的地震曲率属性平面图的交互分析发现,所预测的断裂级别、性质及走向都有较好的对应关系。

The Ordovician carbonate rocks in an area of Tarim Basin are characterized by old geological age, large burial depth and poor developed primary matrix pores, and the favorable reservoir distribution is controlled by faults. So it is very important to carry out the fine prediction of fault in this area. The seismic curvature technique based on horizon was used to predict the fault at the top boundary of Ordovieian Yijianfang Formation. The minimum negative curvature and maximum positive curvature were selected from the commonly used seismic curvatures to describe the fault, and the result shows the good effects. Through the interactive analysis of seismic profile and plane map of seismic curvature based on horizon, it is found that there are good corresponding relations among the level, nature and strike of the predicted faults.