地质力学在地质工程一体化中的应用  

Application of geomechanics in geology-engineering integration

作　　者：鲜成钢 张介辉 陈欣 梁兴 文恒 王高成 

机构地区：[1]斯伦贝谢中国研究院 [2]中国石油浙江油田公司

出　　处：《中国石油勘探》2017年第1期75-88,共14页China Petroleum Exploration

基　　金：国家科技重大专项"云南昭通页岩气开采试验"(2012ZX05018-006);中国石油天然气集团公司重大专项"昭通示范区页岩气钻采工程技术现场试验"(2014F47-02)

摘　　要：四川盆地南部边缘某页岩气田在2014年初投入开发。准确掌握地质力学规律及其在不同尺度应用对保障工程效率和开发效益至关重要,为此建立全区和平台尺度三维地质力学模型。地质力学模型基于高分辨率构造、地质、属性和多尺度天然裂缝模型。通过岩心、测井和地震数据,对力学参数进行了精细表征,发展了一套建立页岩气田三维孔隙压力模型的方法。利用先进的有限元模拟器和大规模并行计算技术,建立全区和平台具有不同平面分辨率的三维应力场模型。为了准确表征页岩的垂向非均质性,模型在目的层具有0.5m的分辨率。充分利用各种数据,对地质力学模型进行质量控制和校正,及时利用新数据对模型进行不断更新。建立的地质力学模型的精度能够反映应力的方向、大小、非均质性和各向异性。结果显示,就地应力在不同平台、井间和沿水平井段都呈现较大变化,这种复杂变化是岩石结构如构造形态和多尺度裂缝系统以及岩石成分在不同尺度变化的必然反映。地质力学模型满足了从全区到单井的不同应用对尺度和精度的不同要求。全区模型用于优化平台位置、井位及部署,评价地质封存性、资源状况,以及评估断裂及裂缝带的力学稳定性等;高分辨率平台模型用于井壁稳定性分析、实时钻井管理、压裂设计优化以及压裂后综合评估等。地质力学模型被充分地结合到地质工程一体化实践进程之中,通过迭代更新和及时应用,充分发挥了提高工程效率和开发效益的作用。这是国内首次在页岩气田开发中建立大规模地质力学模型,所取得的知识和经验具有一定的借鉴价值。A shale gas field at southern margin of the Sichuan Basin commenced production in 2014. For assuring its engineering efficiency and development benefit, it is critical to accurately understand the geomechanics law and its application in various scales. Accordingly, 3D geomechanics models were built in the scales of the whole study area and the platform. These models are high-resolution models based on structure, geology, attributes and multi-scale natural fractures. Core, well logging and seismic data were used to finely describe the mechanical parameters, and a set of methods for establishing 3D pore pressure model for shale gas field was established. Advanced finite element simulator and large-scale parallel computing technology were applied to establish 3D stress field models with different planar resolutions for the whole study area and the platform. In order to accurately characterize the vertical heterogeneity of shale, the models are designed with a resolution of 0.5 m thick in target layers. Various data were utilized for quality control and calibration of these models, and new data were timely used to continually update these models. The accuracies of these models can reflect the direction, size, heterogeneity and anisotropy of the stress. The results show that in-situ stresses vary greatly at platforms, between wells and along the horizontal well sections. Such complex variations are the consequent reflections of rock textures（e.g. structural form, and multi-scale fracture system） and rock composition in various scales. These geomechanics models can meet various requirements for scale and accuracy in different applications in either the whole study area or any single well. The whole-area model can be used to optimize platform location and well location deployment, to evaluate the geologic storage capacity and resources, and to assess the mechanical stability of faults and fractured belts. The high-resolution platform model can be applied in analyzing borehole stability, managing drilling in real-tim

关 键 词：地质工程一体化 地质力学 龙马溪组 页岩气 昭通示范区 

分 类 号：TE122.1[石油与天然气工程—油气勘探]