顺托果勒北区块东河砂岩薄储层预测

Donghe sand rock thin reservoir prediction in the northern of Shuntuoguole-Manjaer area, Tarim basin

东河砂岩储层是塔里木盆地北部地区主要的油气勘探层系,受多期地质运动的影响,东河砂岩受到不同程度的剥蚀,厚度薄,横向变化大,预测比较困难。顺托果勒北区块勘探程度低,没有钻井,没有三维资料,二维测网密度低。根据构造演化史分析,顺托果勒北区块应与相邻的哈得逊油田有相同的构造演化特点,油气成藏特征也应基本相似。为此,利用周边地区的测井资料在顺托果勒北区块进行了波阻抗反演,利用反演结果对东河砂岩的展布特征进行了描述,划分了东河砂岩发育的有利区域。利用频谱成像技术对东河砂岩地层厚度与调谐频率的关系进行了分析,确定了东河砂岩的最佳调谐频率,并通过区域频谱成像处理资料沿层进行了能量追踪,对东河砂岩厚度的变化趋势和空间分布范围进行了解释。在顺托果勒北区块,利用频谱成像技术和波阻抗反演技术对东河砂岩储层进行了预测。结合构造解释结果,优选出一个面积和厚度较大的圈闭,部署了顺托果勒北区块第1口探井,并在深度5 483 m钻遇厚度为40 m的东河砂岩。

Donghe sand rock is the main exploration layer bearing oil and gas northern Tarim basin. Donghe sand rock was denuded in different degrees for suffering multi-term movement. Studied results show that the impedance of Donghe sand rock is higher than that of covering layer. Applying seismic and log data information transform an amplitude section transformed to an impedance section. Promoting vertical distinction recognizes thin reservoir. Based on spectrum image technology, the relation between the variation of thickness and the frequency tuning is analyzed by scanning seismic data; the frequency response characteristic can be determined. Then, the spectrum energy can be tracked along the reservoir after determining the best tuning frequency. Finally, the thickness of Donghe sand rock is calculated in connection with lithologic interpretation by using frequency resolution. Compared with the result of seismic integrated interpretation, spectrum imaging and impe-dence inversion have better effect in predicting thin reservoir.