深层天然气资源评价方法

An assessment method for deep gas resources

通过统计中国365个深度超过3 500 m的天然气藏的储量丰度,确定了储量丰度的7种主要影响因素,即储层岩性、有效储层厚度、孔隙度、含气饱和度、埋藏深度、圈闭类型和所属盆地。以此为基础,建立了计算资源丰度的多因素类比模型。此外,基于资源评价刻度区数据库和各油田历年的探井钻探成功率数据,类比得到评价单元的圈闭面积系数、钻探成功率、有效圈闭面积和圈闭含油面积系数等关键参数,并估算出评价单元的含油气面积。应用案例示范了新模型的使用流程和评价效果,验证了新模型的适用性和有效性。新模型的提出可以对现阶段中国深层油气资源潜力评价起到积极的推动作用。

In this study,a statistical analysis has been conducted on the reserve abundance of 365 natural gas reservoirs of more than3500 m deep in China,which is mainly influenced by seven factors,i.e.,reservoir lithology,effective reservoir thickness,porosity,gas saturation,burial depth,trap type and basin type.Accordingly,a multi-factor analog model is established to calculate out reserve abundance.In addition,based on the China’s database of calibrated areas for petroleum resource assessment and the drilling success rate of exploration wells in each oilfield over the years,the key parameters of assessment units are obtained using an analogy method,such as trap area coefficient,drilling success rate,effective trap area and oil bearing area coefficient of trap,so as to estimate the oil bearing area of each assessment unit.Finally,the operation flow and assessment effect of this method are presented based on an application case,thus verifying its applicability and effectiveness.The proposal of this new method plays an active role in the potential evaluation of deep hydrocarbon resources at the present stage in China.