泌阳凹陷安店区块薄储层精细预测

Detailed prediction of thin reservoir in Andian area of Biyang Depression

泌阳凹陷安店区块勘探目的层为砂泥岩薄互层,砂体厚度一般小于10 m,储层横向变化大,砂、泥岩声阻抗界限不明显,叠前资料缺失大角度信息。探讨了小偏移距条件下的薄储层预测方法——精细反演方法。首先采用两角度弹性阻抗反演方法进行叠前参数提取,并采用统计方法对叠前属性进行优选,得到对安店区块薄砂体的岩性和流体最为敏感的属性——泊松比;然后将叠前反演提取的泊松比数据体作为背景约束,采用高斯配置协模拟方法生成最终的高垂向分辨率泊松比数据体,实现薄储层的精细反演。利用精细反演方法,结合地质、测井等资料对安店区块薄砂体的展布特征进行了描述,并预测了有利储集体。预测结果得到了钻井结果的验证。

In Andian area of Biyang Depression,the target intervals are interbeded,which are characterized by sandbodies less than 10m, severe lateral variation of sandbodies,non-obvious acoustic impedance boundaries of sand and shale,as well as the laek of wide-angle information of pre-stack data of the area.Aiming at the problems, an inversion method for thin reservoir description with small offset is discussed,which is a detailed inversion method.Firstly,pre-stack parameters are extracted with two-angle elastic impedance inver- sion method,and pre-stack properties are optimized by statistic analysis, the Poisson ratio which is the most sensitive parameter to fluid and lithology in Andian area is extracted from pre-stack inversion. Then,the extracted Possion ratio data volume is taken as background constraint,with Gaussian collocated co-simulation method,the high vertical resolution Poisson ratio data volume is obtained to reveal details of the thin reservoir in the area.In Andian area,combined with geologic and log data,the detailed inversion method was used to describe the distribution of thin sandbodies and predict favorable reservoirs.The prediction results were proved by former drilling results.