应用声波全波列测井计算裂缝性含气储层参数

Calculation of gas reservoir parameters by full waveform tools

1. 石油大学(华东)地球资源与信息学院,山东东营257061;2. 大港油田测井公司,天津300280;3. 青海油田分公司,青海敦煌736202

1. Faulty of Earth Resources and Information Technology, University of Petroleum, Dongying 257061, China;2. Dagang Well Logging Company, Tianjin 300280, China;3. PetroChina Qinghai Oil Company, Dunhuang 736202, China

裂缝性气层的解释目前仍存在许多困难, 主要原因是测井特征微弱, 不易识别。在文献总结的基础上, 采用纵波首波幅度比值法、合成横波时差重叠法、纵横波速度比法、等效弹性模量差比法和三孔隙度重叠法等方法定性识别气层, 其目的在于通过突出气层的测井特征来识别气层。引入弹性模量差比计算含气饱和度, 并用一口井的核磁测井差谱结果进行了对比验证。没有横波资料的井, 通过引入纵、横波地区经验关系来获得横波。应用提取的斯通利波也可以计算渗透率。某油田 7口井的处理结果与地质实际吻合, 表明这种方法切实可行, 可以全面评价裂缝性气层。

The interpretation of fractured gas reservoirs is still in difficulty because there is no method that can be used to identify weak log responses convincingly. Based on a review of references, the author proposed to identify the gas reservoirs jointly by the ratio of compressional wave amplitudes, the overlap of the synthetic and measured shear wave slowness, the ratio of compressional wave velocity to shear wave velocity, the relative ratio of equivalent elastic moduli, and the overlap of three porosity logs. The relative ratio of elastic moduli was taken as a new method to compute gas saturation, and the result was verified by NMR logging. Shear wave data was calculated with an empirical relation between shear and compressional waves if the shear wave data was unavailable. Permeability was computed from Stonely waves. Results from data of 7 wells provided by Dagang Oilfield showed the feasibility of the method.