[SSS05-P04] A Novel Method to Estimate Fracture Permeability: Combining microseismic observational data and reservoir engineering model
Keywords:Permeability, Microseismic, Reservoir engineering model
In this paper, we propose a novel method to estimate permeability of each individual fractures which experience shear slip at hydraulic stimulation. The spatiotemporal distribution of reservoir fluid pressure will be estimated using microseismic data. Using a hydromechanical fractured reservoir model, we will invert for the shear-dilation enhanced permeability change that controls the evolution of pressure along fractures and faults.
The first step is to estimate pore pressure distribution with microseismic data from real EGS field and observe how pore pressure migrated within single fracture (Figure 1 left: coloured circles). Meanwhile, using the hydromechanical fractured reservoir numerical model, we simulate pore pressure distribution within one fracture of given permeability and evaluate the evolution of hydraulic properties during a stimulation treatment (Figure 1 right: coloured sold lines). Therefore, we can use parameters from observational data as input parameters into hydromechanical model and estimate the best permeability which explain observed pore pressure distribution. We will also simulate all microseismic clusters and estimate permeability of each fractures. Then analyse the fracture permeability distribution (permeability mapping) in the study area.
In this research, it is the first attempt to estimate local permeability for each fracture. So far, only global permeability can be estimated by wellbore test or microseismic data and this permeability is not effective for each fracture in subsurface. Information of local permeability is quite valuable for designing a sustainable energy extraction system. Local permeability information also brings the way to model the flow of geothermal fluid in the reservoir, which is important for long-term management of geothermal resources.