Tang Y.,China National Offshore Oil Corporation |
Tang Y.,China University of Geosciences |
Tang Y.,Key Laboratory of Shale Gas Resource Exploration and Strategy Evaluation |
Li L.,China National Offshore Oil Corporation |
Jiang S.,China National Offshore Oil Corporation
Natural Gas Industry | Year: 2014
Gas content is a key parameter of shale reservoirs and its interpretation is the core of logging evaluation. Based on a literature review and a comprehensive study, we built a logging interpretation model of shale gas content by using the adsorption isotherm and volume model and discussed the calculation methods of the key parameters of the model. A case study was performed on three shale gas wells in the Toolebuc Shale of the Eromanga Basin in Australia. Based on core experiments, logging interpretation was applied to predict the gas content of the Toolebuc Shale with the integration of the correlativity model and experimental formula. The results matched well with the experimental test results, verifying the rationality of this presented model. The following conclusions were drawn. (1) The gas content logging interpretation model built based on the adsorption isotherm and volume model is applicable to shale reservoirs and its major parameters can be obtained by use of the correlativity model between core experimental results and logging data or empirical formula. (2) The gas content obtained by use of the adsorption isotherm and volume model matches well with the measured values especially for the shale with relatively low gas content. When applied in different areas, the correlativity model should be modified according to core experiment results and logging data. Finally, it is pointed out that separate calculation of free gas content and adsorbed gas content via logging data is the most rational method for shale gas content description. ©, 2014, Natural Gas Industry Journal Agency. All right reserved.