基于干扰试井技术的煤层气储层参数测定

CBM reservoir parameter measurement based on the interference testing technology

为弥补传统注入压降试井测试结果以点代面的问题,提出基于煤层气干扰试井的储层参数测试方法,阐述了其基本原理、测试方法和数据分析依据。以沁水盆地南部1口激动井和4口检测井组成的井组为例,结合该井组前期注入压降法、历史拟合法测试结果,并与干扰试井测试结果进行对比分析。结果表明,煤层气干扰试井法各井测点渗透率接近利用排采数据的历史拟合值,且高于注入压降测值,但3种方法获得数据处于同一数量级之内;煤层气干扰试井技术方法可以反映试验5口井的区域渗透率分布特征,其区域东南方向渗透率较大,即为主裂隙发育方向。结合3种方法测得的参数值对比可知,煤层气干扰试井法既可获得离散点的参数值,又可以获得区域井组的连通性和优势渗流方向,结果有助于认识区域储层参数,为进一步的井网和排采井的布置提供比较直接的数据依据。

In order to remedy the problem of point replacing surface in the results of traditional injection pressure drop test,a CBM reservoir parameter measurement method based on interference well testing was proposed.The basic principle,test method and data analysis basis were described.Taking a well group composed of a stimulation well and 4 observation wells in the south of Qinshui basin as example,the results of earlier injection pressure drop and historical fitting of the well group were compared to the results of interference well testing and analyzed.The results showed that the permeability of different measurement points of the well group approximated the permeability from historical fitting using production data and was higher than the permeability measured from injection pressure drop,but the permeability obtained by the three methods was of the same order of magnitude.The CBM interference well testing technology may reflect the characteristics of the regional permeability distribution of the tested well group consisting of 5 wells,at the southeast direction in the region,i.e the direction of development of the principal fracture,the permeability was higher.By combining the parameter values measured from the three methods,it can be known that the CBM interference well testing can get not only the parameter value of the discrete points,but also the regional connectivity of well group and advantageous seepage direction,the results are helpful to know the regional reservoir parameters,provide direct data basis for the layout of further well grid and production wells.