地震曲率形态指数预测低幅度构造的应用及效果

Application of seismic curvature shape-index to predict the low-relief structure

近年来,低幅度构造油藏作为油气勘探的一个重要接替领域,在油气勘探与开发中日益受到重视,但目前预测低幅度构造的方法均存在一定局限性.本文探索了一种利用地震曲率形态指数预测低幅度构造的新方法,首先对地震数据体进行多窗口倾角扫描,然后对倾角数据体进行多种曲率属性计算从而得到曲率形态指数数据体,将得到的曲率形态指数数据体沿目的层进行数值提取从而获得目的层的曲率形态指数结果,形态指数高值区为低幅度构造高部位.曲率形态指数预测低幅度构造不用解释层位、受人为因素影响小,能够预测更小尺度的低幅度构造,并且预测结果准确率高.此方法在厄瓜多尔T区目的层进行应用,可以预测0.01 m^(2)的小尺度低幅度构造,预测结果与钻井稳合率高,后续部署的2口钻井均获得工业油流,对类似地质条件地区的勘探开发具有一定的借鉴意义.

Low-relief structure reservoir is an important field and is paid more attention in oil-gas exploration and development in recent years. However, prediction methods of low-relief structure are limited more or less. In this paper, seismic curvature shape index is applied to low-relief structure prediction. The method is as follows. First, the seismic data is processed by multi-window dip scan and the curvature shape index data is obtained by calculating curvature attributes of the dip data. Curvature shape index is value extracted along the target layer from the curvature shape index data we got. The structure with large shape index is high position of a low-relief structure. Curvature shape index can predict low-relief structure in smaller scale with high accuracy in spite of horizons interpretation and human factors. The method is applied in a target layer of T zone in Ecuador to predict low-relief structure in small scale with area of 0.01 m;and the coincidence rate of prediction result is high with drilling. 2 wells are drilled subsequently and all produce commercial oil flow. It is reference significant to exploration and development of the area with similar geological condition.