CEE Seminar: Fiberoptic Distributed Sensing of Geothermal and Groundwater Systems

Abstract: We live on a trillion cubic kilometers of molten rock.  Geothermal energy seems like a no-brainer: sink some deep wells, circulate some hot water, and drive some turbines.  How hard can it be?  Really hard, as it turns out.  Now that most of the natural geothermal flow systems have been tapped, we need to make new “Enhanced Geothermal Systems” through artificial fracturing of hot dry rock.  Predicting and characterizing the permeability structure of these engineered systems will require a new monitoring toolbox.  I will discuss some new fiber optic tools that has great potential for monitoring both rock fracturing and fluid flow.  Fiber optic Distributed Temperature Sensing (DTS) and Distributed Acoustic Sensing (DAS) measure temperature and strain every meter or so along kilometers of fiber at resolutions of hundredths of a degree centigrade and nanostrain, respectively.  These technologies can be used in passive or cross-hole modes.  We have demonstrated the applicability of DTS and DAS in shallow fractured systems in preparation for EGS deployment.  The technology will be reviewed briefly, followed by applications and potential applications for geothermal systems, but also for hydrology and contaminant hydrology.

Bio: Matt Becker is the Conrey Chair in Hydrogeology and professor in the Geological Sciences Department at California State University, Long Beach. He holds a bachelor's degree in geology from Michigan State University and a master's degree and doctorate in civil enginering from the University of Texas at Austin. Becker has held positions with Chevron USA, Los Alamos National Labs and the U.S Geological Survey National Research Program. He was a National Academy of Science senior research associate at NASA Goddard Space Center and Fulbright Scholar at the University of Trento, Italy. Prior to arriving at the CSULB, he was an assistant then associate professor of geology at the University of Buffalo. He has been studying fluid flow in fractured rock for 20 years.