尺度数目法在潜山裂缝长度定量研究中的应用

The Application of Scale-Number Method in Quantitative Study of Fracture Length in Buried Hill

摘要: 裂缝性储层油藏描述的难点和重点，在于准确描述裂缝的分布规律和展布特征。JZS油田的太古界潜山裂缝性油藏正是这样的典型。前人研究表明该油田主要为构造成因裂缝，且直接影响开发效果。基于此，本文提出了基于尺度数目法来研究对该油田开发具有显著影响的裂缝分布规律，分为四步：首先，对与油田主力储层同时期野外露头进行地质考察，收集裂缝分布数据；其次基于三维地震资料，利用蚂蚁体追踪断裂系统及较大级别的可能裂缝；再对成像测井图像进行解释，描述小裂缝的分布；最终以幂定律准则，对成像测井、野外露头、蚂蚁体数据进行综合分析，转化至同一尺度下，并分析不同尺度下的差异，进而描述不同级别规模的裂缝分布规律。矿场实践表明，利用该方法得出的裂缝规律，建立的三维裂缝模型，并转化为属性模型后，有效提高了裂缝储层的三维定量化表征成果。

Abstract: The difficulty and key points of buried hill fracture reservoir description are to describe accu-rately the distribution rule and characteristics of fracture. JZS oil field of archean erathem frac-tured buried hill mutation reservoir is facing the same problems. Previous studies have shown that the distribution of the fracture which was mainly caused by tectogenesis which directly in-fluences the reservoir development. In order to study the relationship between scale and number of the fracture, a method using the power-law function was put forward. Firstly, geological investigation was carried out on the outcrops with similar formation-time. Secondly, fracture system was automatic identified through ant body tracking technique based on high frequency 3D seismic data. Thirdly, the image logging interpretation was done in order to describe the small classes fractures. At last, the three sources of data were comprehensively analyzed by power-law method in double logarithmic coordinates to describe the quantitative length distribution of different fracture scales. Field application shows that the elaborate 3D reservoir models using this method can better reflect the actual geological information and effectively improve the history matching.