大庆龙虎泡油田低渗油层伤害机理研究

A Study on the Damage Mechanism of the Low Permeability Payzone in Longhupao Oil Field

大庆龙虎泡油田是大庆外围的一个特低渗油田之一，具有中孔低渗的特征，主要产层为高台子油层的高三、高四组，普遍无自然产能，在钻井、完井和其它各种作业过程中容易受到伤害．据此通过薄片分析、Ｘ—衍射、压汞、铸体分析和室内各种静态伤害试验研究了油层的储集空间、孔隙结构、敏感性等基本特征，分析了油层污染的主要因素及伤害机理．研究表明，水敏和酸敏效应是该油层主要损害因素，从而为油层保护提供了必要的科学依据．

Longhupao Oilfield is one of Daqing outlying oilfields. Its permeability is very low and porosity is medium. Its main producing formation is Gao formation and Gao formation of Gaotaizi payzone without natural productivity. This payzone is subjected to damage in the course of the operations such as drilling, completion etc. The basic characteristics of the payzone, including reservoir space, pore structure, sensitivity etc., are studied by means of slice analysis, X-ray diffraction, mercury injection method, casting analysis and a various of laboratory core static flow tests. The main factors of reservoir contamination and the mechanism of formation damage are analyzed. The study of formation sensitivity shows that water sensitivity and acid sensitivity are the main factors of formation damage. The research result in this paper provides a basis for the reservoir protection in Longhupao Oil Field.