低孔低渗储层损害机理及其保护技术

分析研究了低孔低渗（致密）储层地层损害的机理，认为低孔低渗储层损害机理与中低渗砂岩储层损害机理的主要差别表现在：（1）储层液锁损害（主要为水锁损害）；（2）储层毛细管自吸损害；（3）储层裂缝或微裂缝损害；（4）储层应力敏感性损害等。低孔低渗储层的保护主要体现在防止储层水锁损害和保护对低渗（致密）储层渗透率贡献率最大的孔喉及其裂缝微裂缝这两个方面，屏蔽暂堵钻井完井液技术和保护储层的射孔液、压井液技术是保护低孔低渗储层的两项主要技术，但屏蔽暂堵技术的暂堵机理及其体系配方与中低渗砂岩储层的相比差异很大。

Damage Mechanism and Protection Technology of Low Porosity and Low Permeability Reservoirs

The formation damage mechanism of low porosity and low permeability reservoir was analyzed. The results show and that the main differences of damage mechanisms between low porosity and low permeability reservoir and low/medium permeability sandstone reservoir are reflected in these aspects as follows ： 1） reservoir fluid blocking damage; 2） reservoir capillary self-priming damage; 3） reservoir cracks or micro-cracks damage; 4） reservoir stress sensitivity damage. Protection of the low porosity and low permeability reservoir is mainly reflected in preventing the reservoir water blocking damage and protecting pore throats and micro fractures of the low permeability reservoir. The shielding temporary plugging drilling and completion technology with drilling fluid, and perforating fluid and killing fluid technology are two major technologies to protect the low porosity and permeability reservoir, but temporary blocking mechanism and system formula of the shielding and temporary plugging technology for the low porosity and low permeability reservoir are different from low/medium permeability sandstone reservoirs.