SES-01. Understanding Wastewater Disposal and Induced Earthquakes with an InSAR Time Series Analysis of the Raton Basin, Colorado & New Mexico
Between 2010 and 2015, the Midwestern United States experienced an increase in earthquakes in regions that previously had low seismicity rates. Recent research has linked wastewater disposal wells to human-induced seismicity. For over a decade, the Raton Basin, which straddles the border between southern Colorado and northern New Mexico, has had large volumes of fluid pumped from and injected into the subsurface and has also experienced increased numbers of earthquakes. These earthquakes pose a hazard to local residents and create challenges for energy production. This location also has been the focus of several earthquake studies, allowing for a better understanding of induced seismicity. Our research aims to understand how regional seismicity is changing due to subsurface processes and stress changes, as well as provide insights into the mechanisms driving induced seismicity. We use C-band Sentinel-1A/B interferometric synthetic aperture radar (InSAR) data and perform a differential InSAR (DInSAR) time series analysis using the multidimensional small baseline subset (MSBAS) method to observe regions of potential surface subsidence and uplift in the Raton Basin. MSBAS quantifies displacement over long periods of time using the Small Baseline Subset (SBAS) approach. An advantage to using small baselines is to reduce decorrelation — the breakdown of coherence due to changes in pixel properties between images. We seek to determine whether the spatial relationship between the Basin deformation and anthropogenic activities can help to increase our understanding of the relationship between wastewater injection and seismicity. Furthermore, the DInSAR observations can be used to better constrain mechanical and hydrologic properties in future hydro-mechanical modeling. We anticipate our findings will provide a scientific basis for guiding injection operations in a way that reduces earthquake occurrence, so that local residents, energy producers, and policymakers are aware of the impact and can adjust their future actions.