页岩气资源潜力评价方法

Evaluation method of shale gas resource potential

页岩气作为非常规资源,其烃源岩和储集特征均不同于常规天然气藏,因此,页岩气资源量计算方法应有别于传统常规气藏的资源评价方法。根据中国页岩气发育的地质条件和资料的完善程度,提出了适用于中国页岩气资源的评价方法,主要包括体积法和类比法。高勘探程度区主要采用体积法,低勘探程度区采用类比法。总结归纳了体积法中有效厚度、含气量、含气饱和度和孔隙度4个关键参数的确定方法;建立了类比法计算页岩气总地质资源量中类比参数的取值标准,将有机碳含量、干酪根类型、成熟度、泥页岩单层厚度、脆性指数、孔隙度和埋深7项指标作为页岩气地质条件类比的主要参数。体积法和类比法各有优缺点,在计算页岩气总地质资源量时,需要结合评价区的实际情况,选取合适的资源量评价方法。

Shale gas is unconventional resource.Its characteristics of source rock and reservoir rock are different from that of conven tional natural gas reservoirs.Thus,the shale gas resource calculation method should be different from that of conventional gas reser voir.Firstly,the shale gas resource evaluation method suitable to China is proposed according to the geological conditions of shale gas development in China as well as the availability of data.It mainly includes volumetric method which is suitable for the high de gree exploration area and analogy method which is suitable for the low degree exploration area to calculate the amount of resources.Key parameters of the volumetric method which including the effective thickness,gas content,gas saturation and porosity,are point ed out,and the method for determining these parameters is described.Standards of analog parameter values are proposed and seven indicators including organic carbon content,kerogen type,maturity,shale monolayer thickness,brittleness index,porosity,burial depth are considered as the main parameters of the shale gas geological analogy.The volumetric method and analogy method both have advantages and disadvantages,thus,the total shale gas geological resources should be calculated taking account of the actual situation of evaluation area,and appropriate resources evaluation method should be selected.