Curtin/CSIRO Geophysics Group Seminar, 5th May 2022

Measuring Hydromechanical Strain using Fiber Optic Distributed Acoustic Sensing

Date: Thursday, 5^th of May, 2022
Time: 11:00 AM – 12:00 PM
Location: CSIRO/ARRC Auditorium, 26 Dick Perry Avenue, Kensington
Presenter: Matthew W Becker, Professor of Geology and Conrey Chair in Hydrogeology, California State University, Long Beach, California and 2022 Fulbright Scholar in Resources and Engineering Curtin University

Mapping subsurface hydraulic connectivity and storage is a requirement for petroleum resources, geothermal energy, groundwater resources, and aquifer remediation, among other applications. Hydraulic connections are complex in most geologic environments so measurements of permeability and storativity (compliance) that are averaged over screened or perforated intervals can be very limited in practice. The rapid advancement of distributed fiber optic temperature, vibration, and strain sensing has presented new opportunities to elucidate the hydraulic structure of formations.

Matthew will present our use of fiber optic Distribute Acoustic Sensing (DAS) to measure hydraulic structure in bedrock and unconsolidated media. The technical key is to push DAS to ultra-low frequency so that it can be used as an extremely high resolution (picostrain) distributed strain sensor. Examples from the laboratory and a bedrock field experiment will be discussed, as well as some preliminary results from experiments conducted in the NGL well on Curtin Campus. These results will hopefully stimulate discussion on future applications and interpretations of distributed fiber optic sensing.

Matthew Becker is a Professor of Geology and the Conrey Chair in Hydrogeology in the Geological Sciences Department at California State University Long Beach, California, USA. He holds a B.S. in Geology from Michigan State University and M.S. and Ph.D. in Civil Engineering from the University of Texas at Austin. He has held positions with Chevron USA, and Los Alamos National Labs, and U.S Geological Survey National Research Program. He was a National Academy of Science Senior Research Associate at NASA Goddard Space Centre and was a Fulbright Scholar at the University Trento, Italy. Prior to arriving at the CSULB he was an Assistant then Associate Professor of Geology at the University of Buffalo. His primary focus of research is the hydraulic connectivity of fluid flow in heterogeneous subsurface environments also but has projects in managed aquifer recharge and submarine groundwater discharge.