The Effects of Varying Injection Rates in Osage County, Oklahoma, on the 2016Mw 5.8 Pawnee Earthquake

Research Article| May 03, 2017 The Effects of Varying Injection Rates in Osage County, Oklahoma, on the 2016 Mw 5.8 Pawnee Earthquake Andrew J. Barbour; Andrew J. Barbour aEarthquake Science Center, U.S. Geological Survey, 345 Middlefield Road, Menlo Park, California 94025 U.S.A., abarbour@usgs.gov Search for other works by this author on: GSW Google Scholar Jack H. Norbeck; Jack H. Norbeck aEarthquake Science Center, U.S. Geological Survey, 345 Middlefield Road, Menlo Park, California 94025 U.S.A., abarbour@usgs.govbAlso at Department of Energy Resources Engineering, Stanford University, Stanford, California U.S.A. Search for other works by this author on: GSW Google Scholar Justin L. Rubinstein Justin L. Rubinstein aEarthquake Science Center, U.S. Geological Survey, 345 Middlefield Road, Menlo Park, California 94025 U.S.A., abarbour@usgs.gov Search for other works by this author on: GSW Google Scholar Author and Article Information Andrew J. Barbour aEarthquake Science Center, U.S. Geological Survey, 345 Middlefield Road, Menlo Park, California 94025 U.S.A., abarbour@usgs.gov Jack H. Norbeck aEarthquake Science Center, U.S. Geological Survey, 345 Middlefield Road, Menlo Park, California 94025 U.S.A., abarbour@usgs.govbAlso at Department of Energy Resources Engineering, Stanford University, Stanford, California U.S.A. Justin L. Rubinstein aEarthquake Science Center, U.S. Geological Survey, 345 Middlefield Road, Menlo Park, California 94025 U.S.A., abarbour@usgs.gov Publisher: Seismological Society of America First Online: 15 Sep 2017 Online Issn: 1938-2057 Print Issn: 0895-0695 © Seismological Society of America Seismological Research Letters (2017) 88 (4): 1040–1053. https://doi.org/10.1785/0220170003 Article history First Online: 15 Sep 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Andrew J. Barbour, Jack H. Norbeck, Justin L. Rubinstein; The Effects of Varying Injection Rates in Osage County, Oklahoma, on the 2016 Mw 5.8 Pawnee Earthquake. Seismological Research Letters 2017;; 88 (4): 1040–1053. doi: https://doi.org/10.1785/0220170003 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietySeismological Research Letters Search Advanced Search ABSTRACT The 2016 Mw 5.8 Pawnee earthquake occurred in a region with active wastewater injection into a basal formation group. Prior to the earthquake, fluid injection rates at most wells were relatively steady, but newly collected data show significant increases in injection rate in the years leading up to earthquake. For the same time period, the total volumes of injected wastewater were roughly equivalent between variable‐rate and constant‐rate wells. To understand the possible influence of these changes in injection, we simulate the variable‐rate injection history and its constant‐rate equivalent in a layered poroelastic half‐space to explore the interplay between pore‐pressure effects and poroelastic effects on the fault leading up to the mainshock. In both cases, poroelastic stresses contribute a significant proportion of Coulomb failure stresses on the fault compared to pore‐pressure increases alone, but the resulting changes in seismicity rate, calculated using a rate‐and‐state frictional model, are many times larger when poroelastic effects are included, owing to enhanced stressing rates. In particular, the variable‐rate simulation predicts more than an order of magnitude increase in seismicity rate above background rates compared to the constant‐rate simulation with equivalent volume. The observed cumulative density of earthquakes prior to the mainshock within 10 km of the injection source exhibits remarkable agreement with seismicity predicted by the variable‐rate injection case. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.