煤层气封存单元及其地震-地质综合识别方法初探

煤层含气性与渗透性的空间分布具有强烈的非均一性,基于地质选区理论预测的富集有利区控制精度不能完全适应煤层气开发的空间尺度需求。为将稀疏的钻孔测井资料和空间密集采样的地震资料有机结合起来,实现区块尺度下煤层气富集高产区的精细预测,引入煤层气封存单元的概念,并对其构成要素和基本特征进行了讨论;提出基于地震地质综合研究,识别区块尺度下煤层气封存单元的研究思路和方法。初步研究表明:在煤层气地质理论指导下,以煤层气封存单元的封堵层(带)为研究对象,运用以地震属性分析、地震反演为核心的地震综合解释技术,将构造、围岩岩性及其组合、聚煤前后沉积微相等封堵层(带)构成要素作为主要研究内容,可以实现对煤层气封存单元的识别与划分。

Preliminary discussion on coal bed methane storage unit and its seismic geology comprehensive identification method

For the strong spatial differentiation between the coal bed gas-bearing property and permeability,the control accuracy of the coal bed methane (CBM) favorable accumulation region which identified by the geology selection theory had not met the requirement of CBM exploitation in spatial scale.The concept of CBM storage unit was proposed and its components and essential feature were discussed that just for combining the sparse well log data with the dense seismic data preferably,and then realizing the goal of the detailed prediction for CBM enrichment high-yield region in block scale.The research ideas,contents,methods and work-flow about the CBM storage unit under block scale were also introduced which recognized by seismic and geologic integrated means.Preliminary studies indicated that the CBM storage unit can be identified and classified under the theory guidance of CBM geology through taking the seismic attribution analysis and seismic interpretation techniques as the core technology of the seismic comprehensive interpretation,and taking the analysis of sedimentary micro-facies during coal-accumulating period,tectonic,surrounding rock lithology and their combinations characteristics as research object.