High energy arc composite volume fracturing method for deep shale gas

Abstract

The invention discloses a high energy arc composite volume fracturing method for deep shale gas. The method includes the following steps: (1) performing evaluation on key reservoir parameters; (2) performing perforation position determining and perforation operation; (3) performing optimization on fracture parameters and fracturing construction parameters; (4) performing acid pretreatment operation; (5) performing small test fracturing; (6) performing construction of alternating injection of variable viscosity liquid; (7) placing high energy arc fracturing tools, and performing multi-wave high-energy arc discharging and charging operation; (8) pulling out the high energy arc fracturing tools, and performing injection construction of residual fracturing fluid and proppant; (9) performing displacing operation; and (10) placing bridge plug perforation joint tools, repeating the step (4) and the step (6) - (9), and performing fracturing construction operation of a next section. Therefore,the complexity of volume fracturing fractures of deep complex shale gas can be enhanced, the filling rates of a full-scale fracture system can be enhanced, the effective reforming volume of deep shalegas can be increased, and effects of increasing and stabilizing production after fracturing can be improved.

Description

technical field [0001] The invention relates to the technical field of oil and gas exploitation, and more particularly, to a high-energy arc composite volume fracturing method for deep shale gas. Background technique [0002] At present, the exploration and development of shale gas is gradually advancing to deep layers. For example, in key areas such as southeastern Fuling, Dingshan, Yongchuan, Weiyuan and Nanchuan, the burial depth of shale gas is 3500m or even 4500m. The potential is huge. According to preliminary estimates, China's deep-seated resources in the Sichuan Basin amount to more than 1 trillion cubic meters. At present, commercial development has only been achieved in shale gas with a burial depth of less than 4100m in foreign countries. Deep shale gas fracturing with a burial depth of more than 4100m also has problems such as difficulty in adding sand or even early sand plugging, and the effect of fracturing decreases rapidly. At present, there is no major bre...

AI Technical Summary

Problems solved by technology

[0009] In order to solve the problems in the prior art of deep shale gas rocks with strong plastic characteristics, increased difficulty in fracture initiation and extension, low static pressure in fractures, insufficient fracture width, and low complexity, the present invention provides a deep shale gas High energy electric arc composite volume fracturing method for rock gas