The Enola, Arkansas, Intraplate Swarm of 2001

Other| May 01, 2010 The Enola, Arkansas, Intraplate Swarm of 2001 Ivan Rabak; Ivan Rabak University of Washington Department of Earth and Space Sciences Box 351310 Seattle, Washington 98195-1310 U.S.A. bodin@uw.edu (P. B.) 1Center for Earthquake Research and Information (CERI), University of Memphis, Memphis, Tennessee 2Now at Geodesy Laboratory and PANGA Data Analysis Facility, Department of Geological Sciences, Central Washington, University, Ellensburg, Washington, USA Search for other works by this author on: GSW Google Scholar Charles Langston; Charles Langston University of Washington Department of Earth and Space Sciences Box 351310 Seattle, Washington 98195-1310 U.S.A. bodin@uw.edu (P. B.) 1Center for Earthquake Research and Information (CERI), University of Memphis, Memphis, Tennessee Search for other works by this author on: GSW Google Scholar Paul Bodin; Paul Bodin University of Washington Department of Earth and Space Sciences Box 351310 Seattle, Washington 98195-1310 U.S.A. bodin@uw.edu (P. B.) 3University of Washington, Department of Earth and Space Sciences, Seattle, Washington Search for other works by this author on: GSW Google Scholar Steve Horton; Steve Horton University of Washington Department of Earth and Space Sciences Box 351310 Seattle, Washington 98195-1310 U.S.A. bodin@uw.edu (P. B.) 1Center for Earthquake Research and Information (CERI), University of Memphis, Memphis, Tennessee Search for other works by this author on: GSW Google Scholar Mitch Withers; Mitch Withers University of Washington Department of Earth and Space Sciences Box 351310 Seattle, Washington 98195-1310 U.S.A. bodin@uw.edu (P. B.) 1Center for Earthquake Research and Information (CERI), University of Memphis, Memphis, Tennessee Search for other works by this author on: GSW Google Scholar Christine Powell Christine Powell University of Washington Department of Earth and Space Sciences Box 351310 Seattle, Washington 98195-1310 U.S.A. bodin@uw.edu (P. B.) 1Center for Earthquake Research and Information (CERI), University of Memphis, Memphis, Tennessee Search for other works by this author on: GSW Google Scholar Author and Article Information Ivan Rabak 1Center for Earthquake Research and Information (CERI), University of Memphis, Memphis, Tennessee 2Now at Geodesy Laboratory and PANGA Data Analysis Facility, Department of Geological Sciences, Central Washington, University, Ellensburg, Washington, USA University of Washington Department of Earth and Space Sciences Box 351310 Seattle, Washington 98195-1310 U.S.A. bodin@uw.edu (P. B.) Charles Langston 1Center for Earthquake Research and Information (CERI), University of Memphis, Memphis, Tennessee University of Washington Department of Earth and Space Sciences Box 351310 Seattle, Washington 98195-1310 U.S.A. bodin@uw.edu (P. B.) Paul Bodin 3University of Washington, Department of Earth and Space Sciences, Seattle, Washington University of Washington Department of Earth and Space Sciences Box 351310 Seattle, Washington 98195-1310 U.S.A. bodin@uw.edu (P. B.) Steve Horton 1Center for Earthquake Research and Information (CERI), University of Memphis, Memphis, Tennessee University of Washington Department of Earth and Space Sciences Box 351310 Seattle, Washington 98195-1310 U.S.A. bodin@uw.edu (P. B.) Mitch Withers 1Center for Earthquake Research and Information (CERI), University of Memphis, Memphis, Tennessee University of Washington Department of Earth and Space Sciences Box 351310 Seattle, Washington 98195-1310 U.S.A. bodin@uw.edu (P. B.) Christine Powell 1Center for Earthquake Research and Information (CERI), University of Memphis, Memphis, Tennessee University of Washington Department of Earth and Space Sciences Box 351310 Seattle, Washington 98195-1310 U.S.A. bodin@uw.edu (P. B.) Publisher: Seismological Society of America First Online: 09 Mar 2017 Online ISSN: 1938-2057 Print ISSN: 0895-0695 © 2010 by the Seismological Society of America Seismological Research Letters (2010) 81 (3): 549–559. https://doi.org/10.1785/gssrl.81.3.549 Article history First Online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Ivan Rabak, Charles Langston, Paul Bodin, Steve Horton, Mitch Withers, Christine Powell; The Enola, Arkansas, Intraplate Swarm of 2001. Seismological Research Letters 2010;; 81 (3): 549–559. doi: https://doi.org/10.1785/gssrl.81.3.549 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 2001 Enola earthquake sequence started with an M 4.4 mainshock and was followed by 2,500 earthquakes in two months, confined in a crustal volume of 8 km3, at depths between 4 and 6 km. We have computed precise absolute and relative hypocentral locations using relative travel times based on waveform cross-correlation and a double-difference relative hypocentral location method. Focal mechanisms were computed using P-, SV-, and SH-wave polarities. Highly similar strike-slip focal mechanisms are consistent with the stress regime of the mid-continent province. The swarm volume produced two clusters of earthquakes at different depths and times. We speculate that these clusters represent a system of conduits possibly filled by fluids. The focal mechanisms of the first, seismically deeper sequence show a strong thrust component, while the later and shallower cluster solutions show predominant strike-slip motion. Daily seismicity rates reveal short and sudden increases in activity rather than typical aftershock decay. A b-value of 0.9 is observed for the entire swarm. The sequence appears to recapitulate aspects of a more intense earthquake swarm in the same area in 1981. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.