Geomechanical Considerations for Understanding and Managing Induced Seismicity

Описание: Research completed and presented by Jens-Erik Lundstern, Research Geologist at the U.S. Geological Survey at the PBS-SEPM February Technical Luncheon on February 21, 2023, in Midland, Texas.

Abstract: In the past two decades, induced seismicity has emerged as a concern worldwide. Thanks to a wealth of recent research, the casual mechanisms and general behavior of induced earthquakes are now well understood, and practices for managing induced seismic hazards are improving rapidly. In this presentation, I summarize the physics of induced seismicity, including that these earthquakes are often caused by remarkably modest fluid pressure changes. I focus on the recent increase in seismicity in the Permian Basin, where earthquakes potentially induced by oil and gas operations have occurred since the 1960s alongside modest rates of natural seismicity. For example, the MW5.4 event that occurred in November 2022 near the Culberson–Reeves County line in west Texas was part of an ongoing earthquake sequence that has been linked to deep wastewater disposal. A new stress map for the Permian Basin (figure), part of detailed new stress mapping across North America, includes orientations of the maximum horizontal stress (SHmax) and relative stress magnitudes (style of faulting). By pairing these new-generation stress maps with maps of subsurface faults, it is possible to identify which faults may be the most sensitive to fluid pressure increases associated with wastewater disposal, hydraulic fracturing, or carbon storage.

Biography: Jens Lundstern (Lund Snee) is a research geoscientist at the U.S. Geological Survey who studies tectonics and geomechanics, focusing on induced seismicity, unconventional energy, and the geologic history of the western USA. He received his Ph.D. in Geophysics from Stanford University, where he developed a new-generation map of the state of stress in North America. Dr. Lundstern received his M.S. in Geological & Environmental Sciences also from Stanford, where he studied the tectonic and paleogeographic history of the Great Basin in the western U.S. He has previously studied the Alpine Fault plate boundary system in New Zealand on a Fulbright Fellowship, and his experience includes work for Statoil (now Equinor) as an exploration geologist in the Gulf of Mexico.