Jim Rutledge is part of the Utah FORGE seismic monitoring team lead by Dr. Kristine Pankow at the University of Utah. He brings to the Team an expertise in downhole seismic instrumentation and the monitoring of reservoir microseismicity induced during injection stimulations.
An Enhanced Geothermal reservoir is created and or enhanced through a series of high-pressure injections to fracture, stimulate and connect natural fractures in the host rock. Such a fracture system provides the permeability and surface area required to circulate fluids for mining the earth’s heat. Detecting and locating the resulting microseismicity is the chief diagnostic used to map and monitor the development of that fracture system. In addition to obtaining the basic geometry of the stimulated fracture volume and its temporal growth, geomechanical information can be gleaned from source mechanism results, describing the fracture orientation and sense of displacement that generated the seismic signal.
Jim was employed as an Industry Advisor with Schlumberger’s Microseismic Services for the last 8 years before recently partnering with the FORGE team. At Schlumberger he worked primarily on the interpretation of moment tensor inversion in understanding the basic relationship between fracture propagation and generation of the microseismic signal. He spent most of his career, from 1984 to 2012, as a staff seismologist at Los Alamos National Laboratory. From 2004 to 2012 he also worked as a consultant for Schlumberger Cambridge Research. He received a BS in Geology from Pennsylvania State University and an MS in Geophysics from the University of Arizona. Starting in 1989, Jim has led and participated in several studies that demonstrated the uses of microseismic monitoring in oil, gas and geothermal fields for various applications including: hydraulic fracture monitoring, EOR monitoring, production-induced seismicity, subsidence and well-failure problems, gas storage, as well as subsurface CO2 sequestration. He is widely published on the topic of downhole seismic monitoring and interpretation.
An example of microseismic source locations from numerous injection stimulation stages in map view (left) and the population of source mechanisms for the stage 7 events (right). The lateral completion well is shown red.