Research on small-scale sand fracturing and puff technology

Qian Wang,Zuohao Wu,Jiapeng Zheng,Junkai Lu,Menghong Yu,Z Tan,L Liu

doi:10.1051/e3sconf/202132901001

Abstract

Affected by complex fault blocks, sedimentary environment and reservoir physical properties, Jidong Oilfield generally develops small-scale sand bodies, accounting for 24.2% of the produced reserves of medium and low permeability reservoirs. Such sand bodies rely on elastic energy to develop and are difficult to use effectively. In this paper, through the three-dimensional hydraulic physical model experiment and the analysis of the oil layer-dry layer-mudstone mixed sand body, the reasons that affect the model parameters are obtained. The results show that: the length of the high-permeability reservoir area, the length of the intermediate-permeability dry layer area, the rate of change of permeability parameters, the viscosity of the construction fluid, and the construction displacement have an impact on the effect of fracturing enhanced injection energy storage.

Highlights

Small-scale sand bodies refer to sand bodies whose scale is small and the existing well pattern is difficult to establish an effective displacement relationship
The large-scale model experiment of the rock without natural fractures shows that the fractures form simple fractures with double wings, there are no existing complex fractures, and the reservoir reconstruction volume is limited,see Figure 1
Through triaxial large-scale physical model experiments, it has been pointed out that small-scale sand bodies have the corresponding characteristics, except for the mechanical behavior of artificial fractures when they pass through weak structural surfaces such as natural fractures

Summary

Introduction

Small-scale sand bodies refer to sand bodies whose scale is small and the existing well pattern is difficult to establish an effective displacement relationship. Affected by complex fault blocks, sedimentary environment and reservoir physical properties, Jidong Oilfield generally develops small-scale sand bodies, accounting for 24.2% of the produced reserves of medium and low permeability reservoirs. Such sand bodies rely on elastic energy to develop and are difficult to use effectively. According to the characteristics of small sand bodies in G12 block of Jidong Oilfield, a simulation study of crack propagation was carried out On this basis, a deterministic modeling method was used to establish a fine geological model of the block's work area, and on the basis of cutting and coarsening and reservoir numerical simulation, guided by reservoir numerical simulation results, establish fracturing model, obtain fracturing construction parameters, and guide fracturing design and construction

Three-dimensional hydraulic model experiment

Oil layer-dry layer-mudstone mixed sand body

Model parameter influence analysis

Findings

Conclusion