Current situation and development trend of fracture characterization and modeling techniques in shale gas reservoirs
Received date: 2020-06-04
Revised date: 2020-09-04
Online published: 2021-03-10
Supported by
The National Natural Science Foundation of China(41702359)
The China National Science and Technology Major Project(2016ZX05033003-002)
The quality and production of shale gas are directly dependent on the development of fractures. Especially in the large-scale fracturing development, natural and hydraulic fractures play a significant role. Therefore, there is a growing demand for the quantitative characterization of shale gas reservoir fractures and the development of geological modeling technology. The natural fractures of shale gas reservoirs are mainly composed of structural fractures and non-structural fractures. The former is mainly controlled by external factors such as tectonic stress, while the latter is controlled by internal factors such as rock and mineral composition. The main characterization parameters and prediction techniques of fractures of different scales are various. Natural fracture models for shale gas reservoirs are mainly aimed at largescale and mesoscale fractures, which are respectively established. Hydraulic fracture modeling is more deeply studied in numerical simulation. Considering the current and future technology and production requirements, this paper puts forward and discusses the key directions of natural and hydraulic fracture modeling in shale gas reservoirs from the aspects of multi-information application, multi-technology integration and multi-discipline crossing. Natural fractures require multi-scale and multi-method fusion characterization and modeling. Hydraulic fracturing requires the fusion of multiple information constraints of forward and inverse simulation. Furthermore, combined with the concept of geology-engineering integrated modeling, this paper discusses the inner relationship and development of the geological model of shale gas reservoir from three aspects of model type, data integration and model fusion, so as to guide the efficient development of shale gas reservoirs in China.
Xiao-fei SHANG , Sheng-xiang LONG , Tai-zhong DUAN . Current situation and development trend of fracture characterization and modeling techniques in shale gas reservoirs[J]. Natural Gas Geoscience, 2021 , 32(2) : 215 -232 . DOI: 10.11764/j.issn.1672-1926.2020.09.006
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