Method utilizing logging information for determining optimal perforation layer for SRV fracturing

Abstract

The invention discloses a method utilizing logging information for determining the optimal perforation position for SRV (Stimulated Reservoir Volume) fracturing. The method comprises the following steps: (A) calculating mineral friability index B1 by using conventional logging information, elemental capture spectroscopy logging information and natural gamma spectroscopy logging information; (B) calculating dynamic Young modulus E and dynamical poisson ratio v of each layer section by using acoustic logging information and calculating a mechanical friability index B2 of each layer section; (C) calculating total friability index BTot of the layer sections; (D) calculating confining pressure Pc; (E) calculating rock tensile strength St of the layer sections; (F) calculating an I type fracture toughness value KIC and an II type fracture toughness value KIIC of the each layer section; (G) calculating an inner friction angle of each layer section by using logging information; (H) calculating the reservoir compressibility index Frac of each layer section; and (I) selecting a layer section with a high reservoir compressibility index Frac as the optimal SRV fracturing perforation layer. The method is capable of conveniently and efficiently calculating the compressibility index of each layer section by directly using the logging information, so as to provide decision basis for selecting the optimal SRV fracturing perforation layer and promoting exploitation of shale reservoirs.

Description

technical field [0001] The invention relates to the field of shale gas reservoir exploitation, in particular to a method for optimizing volume fracturing perforation layers by using well logging data. Background technique [0002] As the exploration potential of conventional oil and gas resources declines, the development of unconventional energy becomes increasingly important. According to the U.S. Energy Information Administration's estimate, the global shale gas geological reserves amount to 623×10 12 m 3 , recoverable reserves up to 163×10 12 m 3 , the recoverable reserves of shale gas in China reached 36×10 12 m 3 , has broad development prospects and is the focus of future exploration and development. Due to the characteristics of low porosity and ultra-low permeability of shale itself, hydraulic fracturing stimulation must be carried out in order to realize the economic development of reservoirs. The purpose of hydraulic fracturing stimulation is to maximize th...

AI Technical Summary

Problems solved by technology

Laboratory tests to obtain the above parameters are not only time-consuming but also expensive, which is not conducive to the cost-effective development of shale reservoirs

The existing fracability evaluation model only considers the influence of certain factors, which has little guiding significance for on-site fracturing reconstruction

Currently, there is no cost-effective optimal method for volumetric fracturing of perforated zones in shale reservoirs

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