Introducing PyFaultSlip: A free and open-source tool for the assessment of induced fault slip hazards from deep fluid injection

Induced fault slip is a significant hazard incurred by deep fluid injection operations and is inferred to be the source of recent elevated seismicity in the U.S. midcontinent. Deep fluid injection is commonly used for disposal of wastewater associated with oil and gas development and other industrial activities, enhanced oil recovery (EOR), and carbon capture and storage (CCS). However, easy-to-use tools to investigate hazards associated with disposal are lacking. Here, we present pyFaultSlip, a modular, free, and open-source tool written in Python to assess the likelihood of induced fault slip, using both 2D and 3D mapped geometries. We adopt two different approaches to assessing fault slip tendency, a ‘deterministic’ model that does not consider input uncertainty, and a ‘probabilistic’ model that uses a Monte Carlo approach to assess uncertainty. We show examples using 2D and 3D fault data in Oklahoma and Kansas. This tool is geared towards providing straightforward results that can directly communicate the likelihood of induced slip occurring on specific faults to researchers, operators, regulators, and other stakeholders of deep fluid injection projects.