随机分形压裂水平井缝网参数反演方法

Stochastic fractal model for fracture network parameter inversion of fracturing horizontal well

李宪文 赵振峰 李喆 王文东 丛海龙4

低渗透油气田勘探开发国家实验室，陕西 西安 710021 中国石油长庆油田分公司油气工艺研究院，陕西 西安 710021 中国石油大学（华东）石油工程学院，山东 青岛 266580 中国石化胜利油田分公司东胜精攻石油开发集团股份有限公司，山东 东营 257000

National Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields, Xi′an 710021, China Research Institute of Oil and Gas Technology, Changqing Oilfield Company, PetroChina, Xi′an 710021, China School of Petroleum Engineering, China University of Petroleum, Qingdao 266580, China Dongshengjinggong Petroleum Development Group Company Limited, Shengli Oilfield Company, SINOPEC, Dongying, 257000, China)

页岩复杂水力裂缝网络表征是研究体积压裂水平井渗流规律和产能预测的基础。由于缝网形成机制较为复杂，目前大多数复杂裂缝描述方法都是将主、次裂缝简化为规则排列的裂缝网络系统，无法精细刻画缝网的微结构特征。文中基于体积压裂形成的复杂裂缝分布规律，考虑次裂缝交互的分叉特性和微观形态，运用随机分形理论构建了体积压裂水平井缝网数值模型，准确刻画了复杂裂缝分形几何扩展规则和次级裂缝的相互连通性。在该模型的基础上，研究了复杂裂缝网络结构特征控制参数的变化规律，提出了基于微地震信号和历史产量约束下的随机分形缝网参数反演方法。结果表明，随机分形缝网几何形态和属性具有局部或整体可调节性，为压裂水平井历史拟合以及裂缝参数反演提供了一种新思路。

The characterization of the complex hydraulic facture networks is the basis for studying the flow mechanisms and production prediction of volume fracturing horizontal well in shale reservoirs. Due to the limited knowledge of the fracture network formation mechanism, most of the fracture description methods simplified the main and secondary fractures into regular fracture network systems, which cannot describe the micro structure characterizations. In this paper, based on the law of complex fracture distribution formed by volume fracture, and considering the bifurcation characteristics and microscopic morphology of the interactions of secondary facture, the numerical simulation model for the volume fracture is established based on the fractal bifurcation theory. In the model, the fractal geometry expansion rules of complex fractures and the connectivity characteristics of secondary fractures can be accurately described. The dependence of the controlling parameters on the complex network structures is studied, and a stochastic fractal network model for fracture network parameter inversion is presented based on the micro?鄄seismic signals and historical production constraints. The results show that the geometry and properties of the stochastic fractal network have local or overall accommodation, which provides a new idea for the history matching and fracture parameter inversion of fractured horizontal wells.

10.6056/dkyqt201902015