八面河油田低渗透疏松砂岩地层水平井压裂技术研究

分析研究了八面河油田低渗疏松砂岩油藏面14区沙四段主力含油层4,5,6砂组层间应力差,通过优化压裂规模和控制缝高沟通主力含油小层,提高水平井压后产能。针对面14区沙四段低渗疏松砂岩油藏特点,采用低交联度低温破胶压裂液体系,实现端部脱砂压裂,适当增加支撑剂用量减少因支撑剂嵌入对疏松砂岩人工裂缝导流能力的影响。现场应用产液量和产油量显著增加,水平井压后产能是同区块定向井压后产能的3倍。

Research on Horizontal Well Fracturing Technology Used in Loose Sandstone Formation with Low Permeability

This paper has studied in an analytical way the interlayer stress difference among 4,5 and 6 sand groups of main oil-bearing formation of Member Sha4 of Mian Block 14 of low permeability loose sandstone reservoir in Bamianhe Oilfield.It believes that oil accumulations after pressing can be increased by optimizing fracturing scale and controlling fracture height to link the main oil-bearing layers.In line with the features of the reservoir,it advocates adopting low degree of crosslinking cryogenic broken gum fracturing fluid system to achieve tip screenout fracturing and properly increasing proppant to decrease the impact on man-made fracture conductivity of loose sandstone due to proppant embedment.Practical application brings about significant increase in both fluid production and oil production.Horizontal well productivity after pressing is three times as high as directional well productivity of the same block.