摘要
随着经济的快速发展和对清洁能源需求的持续增长,中国能源供应不足的矛盾日益凸显。中国煤层气资源分布广泛,加速煤层气的勘探开发,是国家能源安全的战略需要。由于煤层气与常规天然气的最大差别是以吸附状态赋存于煤层孔隙内表面,具有独特的成藏分布特征和主控因素,因此相对于常规天然气勘探而言,对煤层气储层预测方法提出了更高要求,而煤层气的岩石物理基础研究更是寻找预测方法的着手点和立足点。考虑到中国沉积煤层的多样性,通过选择不同煤阶、煤岩和煤质的岩样,通过实验室岩样参数测试和实际钻井数据分析,确定了模量属性对吨煤含气量检测比较敏感,同时在密度和纵波速度2个属性中,密度对吨煤含气量敏感性优于纵波速度,据此建立了地震煤层气三参数弹性模量(拉梅常数相对变化量、剪切模量相对变化量、密度相对变化量)反演方法。通过四川省蜀南煤层气资料的三参数弹性模量反演实例,证明了模量相对变化量异常可以有效预测煤层气储层富集高产区域,5口井的预测效果和煤层气生产井相吻合,提高了煤层气勘探开发部署井的成功率,为蜀南煤层气的勘探开发和一亿立方米产能建设提供了有力支持。
With the rapid economic development and sustained growth in demand for clean energy,the contradiction of China's energy supply shortage is increasingly highlighted.The wild distribution of China's coal-bed methane (CBM) resources accelerates the exploration and development of CBM.It is the need of national energy security,and conforms to the new energy strategy of CNPC.Because the biggest difference between the CBM and the conventional gas is that the gas adsorption in coal pore surface,and CBM has the distinctive feature of reservoir distribution characteristics and controlling factors, compared with the conventional natural gas exploration,the exploration aiming for CBM reservoir physical & gas-bearing property, has higher requirement on data quality, prediction method and information content.Basic research on the rock physics is the starting point and foothold of CBM prediction method.Considering the diversity of sedi- mentary coal seam in china, by selecting the coal sample with different coal rank, different coal rock and different coal quality, through the laboratory testing parameters and actual drilling data analysis, we confirmed that the modulus properties are more sensitive to the tons of coal containing gas,and between the p- wave velocity and density,the density is more sensitive to the tons of coal containing gas than P-wave velocity.According to this,we established the CBM seismic three-parameter elastic modulus (lame constant relative variation,shear modulus relative variation, density relative variation) inversion method. Through the instance of Southern Sichuan,we proved that the relative modulus variation can effectively predict the enrichment of CBM enrichment region.Prediction of 5 wells agrees with the production, which improve the success rate of the deployment CBM well.
出处
《天然气地球科学》
EI
CAS
CSCD
北大核心
2017年第2期287-295,共9页
Natural Gas Geoscience
基金
中国石油集团公司物探重点实验室新技术新方法项目(编号:2014A-3612)资助
关键词
煤层气
岩石物理
吨煤含气量
模量属性
三参数反演
CBM
Rock physics
Tons of coal containing gas
Elastic modulus
Three-parameter inversion