Key technologies for hydraulic fracturing of normal pressure shale gas in the Zheng’an area of Guizhou

Abstract:

The shale gas reservoir in the Zheng’an area is characterized with normal pressure， thin high-quality shale gas interval and large difference in horizontal principal stresses， leading to difficulties in forming complex fracture network， and in turn， restricting the increase of shale gas production. In view of the difficulties， the fracturing technology system， which mainly composes of multiple clusters of close cutting fracturing in horizontal well sections， fine fracturing design of horizontal wells， variable viscosity fracturing fluid systems with frictional pressure reduction， temporary plugging diversion and flowback fluid reuse， has been formed through the analysis of normal pressure shale gas horizontal well fracturing technology and application in the Zheng’an area in the context of the geological characteristics of the Wufeng-Longmaxi shale gas formation in the area， and referring to the advanced fracturing technology of shale gas in southern China. The technology has achieved good reservoir stimulation and production effect， which provides a strong support for the effective development of shale gas in the Zheng’an area.