摘要
大多数碳酸盐岩储层需要酸化、酸压处理，酸蚀后岩样的流体敏感性行为具有重要研究价值。以往对碳酸盐岩储层的敏感性研究集中于应力敏感和碱敏或者常规的流体敏感性，酸蚀后岩样的流体敏感性研究几乎为空白。文章以四川盆地某典型碳酸盐岩储层为研究对象，进行酸蚀后岩心速敏、水敏实验，并与常规速敏、水敏实验对比。结果表明，常规速敏评价损害程度弱中等，酸蚀后增至中一强；酸蚀后岩样水敏性程度整体有加强的趋势。酸蚀后岩心基质变得疏松，孔缝中微粒容易脱落，产生微粒运移。伊利石、绿泥石分散／运移及硬石膏水化膨胀、溶解一再沉淀是储层酸蚀后水敏性加强的主要原因。碳酸盐岩储层在酸化、酸压等增产措施中应该重视酸蚀后敏感性的强化问题，加强实验评价。
Most of the carbonate reservoirs need acidization or acid fracturing, so it is important to research the samples′ fluid sensitivity after acid etching. In the past, the main research was on stress sensitivity and alkali sensitivity or conventional fluid sensitivity, the fluid sensitivity of the samples after acid etching has never been researched. In this paper, a typical carbonate reservoir in Sichuan basin was selected and the experiments of velocity sensitivity & water sensitivity before and after acid etching were compared. Results show that the valuation of damage degree of conventional velocity sensitivity is weak to moderate, after acid etching it is moderate to strong. The degree of water sensitivity has the tendency to strengthen after acid etching. The core matrix becomes loosely, and the particles in the fractures are easy to shatter and migrate after acid etching. The main reasons of the water sensitivity′s strengthening after acid etching are the diffusion & migration of illite and chlorite, and hydration expansion, dissolution- precipitation of anhydrite. The enhancement of the sensitivity of carbonate reservoir during acidization and acid fracturing should be valued and the experiment evaluation should be strengthened.
出处
《钻采工艺》
CAS
北大核心
2007年第1期105-107,150,共3页
Drilling & Production Technology
基金
油气藏地质及开发工程国家重点实验室基金项目(PLN9720)。
关键词
碳酸盐岩
储层
酸蚀
速敏
水敏
粘土矿物
Carbonate reservoir, acid etching, velocity sensitivity, water sensitivity, clay minerals
