Abstract:

The deep reservoirs are mainly referred to as the 5th sand layer in the lower part of the 3rd member of Hetaoyuan Formation and Dacangfang Formation in Biyang sag,they are characterized by their low porosity and low permeability.These oil/gas reservoirs have been damaged heavily in the course of drilling,well completion, perforation and testing.As a result,the oil/gas reservoirs would often be difficult to be found,and the productivity of those reservoirs with low porosity and permeability would be relatively low.Well productivity can only be increased by stimulation treatment.Through various studies, reservoir protection and stimulation techniques, such as formula of high quality drilling fluid, temporary plugging method and advanced reservoir protection technique with polymeric alcohol,high quality perforation fluid and underbalanced perforation,have been applied,and significant results have been obtained in Zhaowa-Anpeng area.As for stimulation, optmimization of high quality fracturing fluid has also been made,which are characterized by its heat-resisting quality,good compatibility, low friction resistance,and high proppant-carrying capacity.Besides,application and dissemination of large-scale fracturing technology have also been made in Zhaowa-Anpeng area,which prove to be highly effective.

Key words: deep strata, low porosity, low permeability, oil and gas reservoir, reservoir protection and stimulation techniques, Biyang sag