Investigating Large-Scale Physical and Statistical Correlations Associated with Induced Seismicity

Session: Mechanisms of Induced Seismicity: Pressure Diffusion, Elastic Stressing and Aseismic Slip [Poster]
Type: Poster
Date: 4/29/2020
Time: 08:00 AM
Room: Ballroom
Description: 

Wastewater disposal, hydraulic fracturing and hydrocarbon production are all types of subsurface industrial processes that have been shown to induce seismicity across the globe. However, the geological controls that help to promote induced seismicity remain poorly understood. Furthermore, it is not known why the respective roles of different triggering processes, such as pore pressure diffusion, poro-elastic stress transfer and static elastic stress transfer, vary from place-to-place.

To answer these questions, we need to integrate statistical and numerical subsurface models from a variety of regions where induced seismicity is observed, particularly in areas where detailed injection and production rates are recorded independently. Here, we present large-scale numerical pore pressure diffusion and poro-elastic stress transfer models based on monthly reported fluid injection and production data. We are currently applying our approach to the Delaware Basin in Texas, where there has been a sharp increase in recorded seismicity since 2009. It is currently unclear as to whether this earthquake sequence is mainly caused by fracking, wastewater disposal or oil production. We also use multivariate regression to find whether strong correlations exist with geological parameters, such as depth-to-basement and distance to mapped faults. Our initial results show a strong correlation between earthquake occurrence and pore pressure increase due to wastewater fluid injection, although the absolute pressure change values are small (<0.02 MPa).

Presenting Author: Stephen P. Hicks

Authors