【摘要】 页岩含气量主要包括游离气含量和吸附气含量,其中游离气含量的影响因素有孔隙度、含气饱和度、密度、压力、温度等,而影响吸附气含量的因素有有机碳含量、有机质成熟度、压力、温度等。不同有机质类型的页岩吸附能力(吸附量/有机碳含量)差别较大,且Ⅲ型>Ⅱ型>Ⅰ型,并分别建立了游离气含量和吸附气含量的计算公式。为了快速、准确地获取页岩含气量,分析并筛选了页岩含气量主控关键参数,基于含气量理论计算公式等相关理论计算得出不同有机质类型的页岩含气量图版。总体上,页岩含气量随深度增加而变大,但变大趋势逐渐降低。页岩含气量图版理论值与页岩现场测试含气量相关性拟合表明图版具有广泛的实用性。在页岩气勘探初期地质参数较少的情况下,页岩含气量图版的建立从理论上预测含气量,为合理评价页岩气资源潜力和预测有利区提供了依据。更多还原

【Abstract】 Shale gas content is composed of free gas contentand adsorbed gas content.The free gas content may be influenced by porosity,gas saturation,density,pressure and temperature,whilethe adsorbed gas content is affected by organic carbon content,organic matter maturity,pressure and temperature.The adsorption capacities of organic matters of different types(adsorption / TOC) of shale are quite different,and show the sequence of Ⅲ > Ⅱ > Ⅰ.Thus,different formulas were proposed for the calculation of free gas content and adsorbed gas content.Through analyzing and selecting the key factors for shale gas content,and based on relational theoretical calculations,charts of shale gas content were developed for different organic matter types,so as to quickly and accurately calculate shale gas content.Overall,shale gas content increases with depth,but the increment decreases progressively.The theoretical values calculated with the charts correlate well with the field measured values,indicating the wide applicability of these charts.The theoretical shale gas content obtained with these charts can provide a reliable basis for the reasonable evaluation of shale gas resource potential and prediction of play fairways in the early stage of shale gas exploration when the available geologic parameters are rare.更多还原