川南页岩气峰值产量预测

Prediction on peak production of shale gas,southern Sichuan Basin

中国页岩气资源主要分布在四川盆地及邻区,四川是中国最早进行页岩气勘探开发的盆地,发展潜力巨大。产量峰值预测研究是指导页岩气发展的重要依据,以研究四川盆地南部地区页岩气的勘探开发潜力为基础,通过对国内外预测模型的筛选和适用性分析,采用Gauss与Hubbert模型预测川南页岩气产量增长趋势。综合考虑影响页岩气产量预测的关键因素,以期实现储量发现与产量增长预测的有效联动。将最终可采储量(URR)作为影响产量变化趋势的综合表征指标,创新建立以最终可采储量为约束条件的储—产量耦合预测模型,并在不同最终可采储量情景下,对川南页岩气未来产量峰值进行较高精度的量化预测。研究结果表明:①在未来一段时期,川南页岩气具有广阔的勘探开发前景,峰值产量与最终可采储量呈正相关关系;②研判达到峰值时间,从历史拟合出发,预测产量达到峰值时间在2042年左右;③对于峰值产量区间,峰值产量预测结果证实,两种模型预测不同情景最终可采储量下的峰值产量接近,川南页岩气产量高峰区间中值在350×10^(8)~400×10^(8) m^(3),相对稳产期10年以上。

China’s shale gas resources are mostly distributed in Sichuan Basin and its adjacent areas.With huge exploitation potential,this basin is the first one in China to carry out shale gas exploration and development.Prediction on the peak production of shale gas is the key evidence for guiding its development.So,according to the study on exploration and development potential of shale gas in southern Sichuan Basin,the production growing trend was predicted exclusively by using Gauss and Hubbert models after screening domestic and foreign prediction models and analyzing their applicability.The main influential factors on this prediction were fully taken into consideration to realize an effective linkage between reserve discovery and production growing prediction.With the ultimate recoverable reserves(URR)as an overall indicator affecting the production trend,one model of coupling reserve-production prediction was established by taking ultimate recoverable reserves as the constraint.Furthermore,under different scenarios of ultimate recoverable reserves,a high-precision quantitative prediction was performed on the future peak production of shale gas in southern basin.Results show that(1)shale gas in southern Sichuan Basin boasts a vast prospective of exploration and development for some time to come,and its peak production is positively correlated with the ultimate recoverable reserves;(2)it is predicted from history matching that the production will top around 2042;and(3)it is confirmed close peak production under different scenarios predicted by the two models,and the median peak production of shale gas in southern Sichuan Basin ranges from 350×10^(8) m^(3) to 400×10^(8) m^(3),and this production will maintain stable for more than 10 years.