Research on Quantitative Characterization of 3D Fractures Induced by Hydraulic Fracturing: Insights from Experimental Analysis and Mathematical Models

Hydraulic fracturing (HF) is a widely used reservoir reconstruction technology in unconventional oil and gas development. Quantitative characterization of hydraulic fracturing fracture (HFF) is an important way to explore the mechanism of HFF extension and evaluate the stimulation effect of HF. In this study, based on development of HF physical simulation experiments and establishment of mathematical calculation models, the quantitative characterization of fractures induced by HF was systematically explored. The HFF communication area, reservoir reconstruction volume, fractal dimension, and other overall fracture geometry parameters were established. The local geometric characterization parameters of HF such as fracture aperture and fracture occurrence were created. To solve the problem that the calculation of the diameter of the central axis ball was tedious and cannot completely describe the fracture opening, a method to estimate the fracture opening using the shape diameter function was established, and its systematic error was corrected. The mathematical calculation model of HFF seepage properties was established, which is applicable to any complex planar fracture network and provides a new numerical calculation tool for simulating the flow in the fracture. The characteristics of HFF under different compression and shear loads were compared. A systematic quantitative characterization method of HFF was presented.The error of estimating fracture aperture by shape diameter function was corrected.The mathematical calculation model of seepage properties was established.