碳酸盐岩气藏控制及预测储量区块升级评价方法

Evaluation methods for the upgraded controllable and predicted reserves in carbonate gas reservoirs

四川盆地碳酸盐岩气藏控制及预测储量升级潜力评价方法大多以定性描述为主,实际应用中具有一定局限性。为此,以优选可升级控制、预测储量区块为目的,从储量升级特点入手,筛选影响储量升级的关键因素,建立升级评价体系,引入升级系数定量评价储量区块的升级潜力,建立了一套具有较高适用性和较强可操作性的储量升级潜力定量评价方法。应用结果表明:①储量规模、储量品质、储层物性以及勘探投入等因素对储量升级具有直接影响,储量规模、千米井深稳定产量、储量丰度等指标对储量升级影响程度较高;②分类指标升级系数表明,升级系数与储量品质、储量规模、储层物性、勘探投入呈正相关关系,升级系数越高,升级潜力越大;③同一地区不同层系,由于含油气地质条件不同,升级标准也有所差异,应当分层系开展评价。

Although it is a common practice in carbonate gas reservoirs,Sichuan Basin,a qualitative evaluation on upgraded controllable and predicted reserves has some limitations.To optimize the prospect to upgrade both reserves,the key factor affecting this upgrade was found out.Furthermore,a set of quantitative evaluation methodology was developed,including an evaluation system and a upgraded coefficient.Results show that(1)for reserves,the upgrade is directly related to their size and quality,reservoir property,and exploration investment,particularly the size,stable rate of production per kilometer well depth,and reserve abundance;(2)the upgrade coefficient for each classification indicator is positively correlated with the reserve quality and size,reservoir property,and exploration investment.The higher the coefficient,the larger the upgraded possibility;and(3)upgraded criteria may vary with different strata in the same prospect due to different geologic accumulation condition.Thus,to evaluate the upgraded reserves should be performed separately for each stratum.