花岗岩潜山储层裂缝建模表征方法——以渤海花岗岩潜山A油田为例

花岗岩潜山油气藏在世界范围内并不多见，当前对其表征还未形成系统完善的研究方法；同时，由于储层受风化、构造多种作用改造，导致储层内部孔、缝、洞并存，具有极强的非均质性，对其表征存在一定的难度。为此本文以渤海大型花岗岩潜山A油田为例，提出了一套花岗岩潜山储层建模表征方法。首先从成因分析入手，引入地貌学分析方法，通过地貌演化特征分析，确定裂缝发育主控因素，在此基础上建立不同成因的裂缝分布趋势体。其次，以井点统计的裂缝特征参数为先验信息，以裂缝分布趋势体为平面约束，建立DFN模型，并对其进行“等效”得到裂缝属性模型。最后，采用动静态资料对裂缝属性模型进行优选，严格控制模型质量，最终得到符合地质认识的裂缝模型。

Granite Buried Hill Reservoir Characterization and Modeling: Taking Offshore a Oilfield in Bohai Bay as an Example

Granite buried hill reservoir is rare in the world. No systematic research method on fracture characterization of granite buried hill reservoir has been formed so far. Meanwhile, as the reservoir was multiply reconstructed by tectonic, weathering and erosion processes, pores, fractures and caves developed inside together. So it’s difficult to characterize the reservoir as fractures developed with strong heterogeneity. For this reason, the article proposed a set of methods for fracture characterization and modeling of granite buried hill reservoir, taking offshore oilfield A in Bohai Bay as an example. Firstly starting from fracture genetic analysis, geomorphologic analytic method is introduced to determine main controlling factors of fracture distribution with evolutionary characteristic analysis. On the basis above, fracture development trend models of different genetic types are established. Secondly, with advanced DFN method, the DFN model is built with statistical fracture parameters of well point as prior information and fracture trend models as constraint condition, then fracture attribute models have been abtained with upscaling method. Finally fracture attribute models are verified and optimized with static and dynamic data. With the two methods of verification for quality control of fracture model, the ultimate fracture model is accordant with the geological understanding.