The measurement of shale gas content using isotherm desorption method for the complex Jurassic shale-mudstone-sand⁃stone-coal rock system was conducted with cores from the Chaiye-1 well drilled in Qaidam Basin. According to the data achieved, methodology for measuring shale gas content of rocks with isotherm desorption method was discussed based on practice. First, the shale gas desorption curve of rocks commonly exhibits multiple desorption peaks, due to the fact that the shale gas in rock represents not on⁃ly adsorbed gas but also physically bound gas, and it desorbs when the micro physical structure in the rock is altered by the desorption process. Second, the lost shale gas portion of the rocks should be restored with the desorption data achieved at the early stage, which represents desorption of adsorbed gas at a stable manner. Third, residue gas of the rocks should only be measured by cracking the rocks to powder, since it is physically enclosed in the rocks. Fourth, shale gas in cores can be measured with isotherm desorption method later after the cores are canned and sealed in the desorption chamber without unreasonably data discrimination within 30 days.%岩石含气量是页岩气资源量评价及勘探开发的关键性技术指标，其测试技术与方法尚处于发展与完善过程中。利用恒温解析-氢火焰离子检测法对柴达木盆地柴页1井侏罗系大煤沟组不同岩性的岩心进行了页岩气解析测试，通过对解析曲线和含气量数据分析研究发现：①页岩气解析测试的气体释放过程包括一系列的复杂解析过程，而非简单的解吸附过程，具有多级性，其解析速率曲线表现出多峰性；②岩石中吸附气的解吸量在早期恒温解析阶段遵循USBM直线规律，这一时间段的解析数据适合于计算损失气量；③岩石中的残余气是被岩石的物理构造所限滞的气体部分，应该在将岩石粉碎后测定；④将含页岩气岩心短期封存对于解析气测定结果的影响不大，在30天内完成测试即可。这些认识对于页岩气解析测试技术方法的改进、完善与规范具有重要参考价值。
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