【作者】 郑环； 李沁； 陈文玲； 罗志彬； 张琴；

【机构】 成都理工大学能源学院； 油气藏地质及开发全国重点实验室(成都理工大学)；

【摘要】 酸蚀裂缝导流能力是评价碳酸盐岩酸压成效的核心指标,对碳酸盐岩储层产量有直接影响。针对当前深层、高温高压储层的改造,稳定高效的导流能力尤为关键。碳酸盐岩储层酸蚀裂缝的闭合形态决定了其导流能力的大小,然而酸蚀裂缝在闭合过程中,由于酸蚀裂缝面岩性分布与岩石力学性质非均质性较强,表面酸岩反应模式复杂难以研究,导致酸蚀裂缝长期导流能力变化规律难以预测。本文基于酸岩反应基本理论,以白云岩和灰岩为研究对象,采用室内试验、理论分析等方法,揭示了岩石矿物成分含量和酸蚀前后力学性质变化对酸蚀裂缝导流能力的长期影响规律,分析不同条件下酸蚀裂缝导流能力的变化趋势。分析结果表明:快反应矿物含量与导流能力呈显著正相关关系,非反应矿物含量与导流能力呈负相关关系;酸蚀前后岩石力学性质变化对长期导流能力影响较大,杨氏模量与长期导流能力呈正相关关系,泊松比与长期导流能力呈负相关关系,并且杨氏模量对长期导流能力影响大于泊松比。更多还原

【Abstract】 The conductivity of acid-etched fractures is the core indicator for evaluating the effectiveness of acid fracturing of carbonate rocks and has a direct impact on the production of carbonate rock reservoirs. For the current transformation of deep, high-temperature and high-pressure reservoirs,stable and efficient flow conductivity is particularly critical. The closed shape of acid-etched fractures in carbonate reservoirs determines their conductivity. However, during the closing process of acid-etched fractures, due to the strong heterogeneity of the acid-etched fracture surface lithology distribution and rock mechanical properties, the surface The reaction model of acid rock is complex and difficult to study, making it difficult to predict the long-term conductivity changes of acid-etched fractures. Based on the basic theory of acid-rock reaction, this article takes dolomite and limestone as the research objects, and uses methods such as laboratory experiments and theoretical analysis to reveal the long-term effects of rock mineral composition content and changes in mechanical properties before and after acid etching on the conductivity of acid-etched fractures. regularity, and analyze the changing trend of conductivity of acid-etched fractures under different conditions. The analysis results show that: there is a significant positive correlation between the content of fast-reacting minerals and the conductivity, and there is a negative correlation between the content of non-reactive minerals and the conductivity; the changes in rock mechanical properties before and after acid etching have a greater impact on the long-term conductivity, Yang’s There is a positive correlation between modulus and long-term conductivity,and a negative correlation between Poisson’s ratio and long-term conductivity, and Young’s modulus has a greater impact on long-term conductivity than Poisson’s ratio.更多还原