复合曲流河道内的单河道识别

Single channel identification in a meandering river with compound channels

随着油气田开发程度的深入,复合河道砂体尺度的研究难以满足生产需求,需要开展单河道砂体边界的识别。埕海一区明化镇组曲流河河道频繁地决口、改道和侧向迁移,复合河道砂体较为发育。依据单河道砂体接触部位地震波形及振幅发生变化的特点,首先利用边缘检测属性突出岩性变化引起的振幅响应,识别出单河道的边界;再利用倾角方位属性能够反映地震波形的细微变化,预测单河道的侧向迁移方向;借助上述方法识别研究区单河道的边界,并且精确预测了单河道点坝砂体的具体位置。预测结果与钻井吻合程度较高,有效地指导了井网关系调整及剩余油挖潜,也为类似地区的单河道识别与划分提供了一种新的方法。

With the oilfield development, the composite channel sand description is not enough for the oil production, so it is necessary to carry out the identification of single-channel sand boundaries. Composite channel sand bodies were well developed as the meandering river in District 1 of Chenghai encountered frequent breachs, diversions and lateral migrations. First we highlight amplitude response caused by lithology with the edge detection attribute based on characteristics of waveform and amplitude variations at single channel sand bodies, and identify single-channel boundaries. Then we use DipAzi attribute to find out slight changes of waveforms and predict the lateral migration direction of every single channel. Single-channel boundaries can be identified together with these two attributes, and accretion sand positions in a single channel can be accurately predicted. Our prediction matches very well with the later drilling, which is helpful for the remaining oil production in the study area and provides a new idea for the single channel recognition.