Estimating Un-propped Fracture Conductivity and Fracture Compliance from Diagnostic Fracture Injection Tests

TL;DR

This paper introduces a new method to estimate fracture conductivity and compliance from diagnostic fracture injection tests, aiding subsurface fracture characterization crucial for various energy and environmental applications.

Contribution

It presents a time convolution solution to analyze pressure transients, enabling estimation of fracture properties as functions of effective stress from field data.

Findings

Effective stress-dependent fracture conductivity and compliance can be accurately estimated.

The method improves understanding of fracture behavior under different stress conditions.

Application potential in fault zone analysis, CO2 sequestration, and geothermal energy.

Abstract

Fractures are ubiquitous in the subsurface. The flow and mechanical properties of these fractures are controlled by its compliance or stiffness. Characterizing fracture compliance and conductivity is crucial in applications such as fault zone studies, underground CO2 sequestration, nuclear waste repositories, geothermal energy exploitation and hydrocarbon reservoir development. In this study, we present a time convolution solution of pressure transient behavior of a closing fracture. From Diagnostic Fracture Injection Tests, our presented method can be used to estimate subsurface fracture conductivity and compliance as a function of effective stress.