Slow slip source characterized by lithological and geometric heterogeneity

Philip M Barnes; Laura M Wallace; Demian M Saffer; Rebecca E Bell; Michael B Underwood; Ake Fagereng; Francesca Meneghini; Heather M Savage; Hannah S Rabinowitz; Julia K Morgan; Hiroko Kitajima; Steffen Kutterolf; Yoshitaka Hashimoto; Christie H Engelmann de Oliveira; Atsushi Noda; Martin P Crundwell; Claire L Shepherd; Adam D Woodhouse; Robert N Harris; Maomao Wang; Stuart Henrys; Daniel H N Barker; Katerina E Petronotis; Sylvain M Bourlange; Michael B Clennell; Ann E Cook; Brandon E Dugan; Judith Elger; Patrick M Fulton; Davide Gamboa; Annika Greve; Shuoshuo Han; Andre Hüpers; Matt J Ikari; Yoshihiro Ito; Gil Young Kim; Hiroaki Koge; Hikweon Lee; Xuesen Li; Min Luo; Pierre R Malie; Gregory F Moore; Joshu J Mountjoy; David D McNamara; Matteo Paganoni; Elizabeth J Screaton; Uma Shankar; Srisharan Shreedharan; Evan A Solomon; Xiujuan Wang; Hung-Yu Wu; Ingo A Pecher; Leah J LeVay; IODP Expedition 372 Scientists

doi:10.1126/sciadv.aay3314

Slow slip source characterized by lithological and geometric heterogeneity

Sci Adv. 2020 Mar 25;6(13):eaay3314. doi: 10.1126/sciadv.aay3314. eCollection 2020 Mar.

Authors

Philip M Barnes¹, Laura M Wallace², Demian M Saffer³, Rebecca E Bell⁴, Michael B Underwood⁵, Ake Fagereng⁶, Francesca Meneghini⁷, Heather M Savage⁸, Hannah S Rabinowitz⁹, Julia K Morgan¹⁰, Hiroko Kitajima¹¹, Steffen Kutterolf¹², Yoshitaka Hashimoto¹³, Christie H Engelmann de Oliveira¹⁴, Atsushi Noda¹⁵, Martin P Crundwell², Claire L Shepherd², Adam D Woodhouse¹⁶, Robert N Harris¹⁷, Maomao Wang¹⁸, Stuart Henrys², Daniel H N Barker², Katerina E Petronotis¹⁹, Sylvain M Bourlange²⁰, Michael B Clennell²¹, Ann E Cook²², Brandon E Dugan²³, Judith Elger¹², Patrick M Fulton²⁴, Davide Gamboa²⁵, Annika Greve²⁶, Shuoshuo Han²⁷, Andre Hüpers²⁸, Matt J Ikari²⁸, Yoshihiro Ito²⁹, Gil Young Kim³⁰, Hiroaki Koge³¹, Hikweon Lee³⁰, Xuesen Li³², Min Luo³³, Pierre R Malie³⁴, Gregory F Moore³⁵, Joshu J Mountjoy¹, David D McNamara³⁶, Matteo Paganoni³⁷, Elizabeth J Screaton³⁸, Uma Shankar³⁹, Srisharan Shreedharan³, Evan A Solomon⁴⁰, Xiujuan Wang⁴¹, Hung-Yu Wu²⁶, Ingo A Pecher⁴², Leah J LeVay¹⁹; IODP Expedition 372 Scientists

Affiliations

¹ National Institute of Water and Atmospheric Research (NIWA), Wellington 6021, New Zealand.
² GNS Science, Lower Hutt 5011, New Zealand.
³ Department of Geosciences and Center for Geomechanics, Geofluids, and Geohazards, The Pennsylvania State University, University Park, PA 16802, USA.
⁴ Basins Research Group, Imperial College London, Exhibition Road, Kensington SW7 2AZ, UK.
⁵ Department of Earth and Environmental Science, New Mexico Institute of Mining and Technology, 801 Leroy Place, Socorro, NM 87801, USA.
⁶ School of Earth and Ocean Sciences, Cardiff University, Park Place, Cardiff CF10 3AT, UK.
⁷ Dipartimento di Scienze della Terra, Università degli Studi di Pisa, via. S. Maria, 53, Pisa 56126, Italy.
⁸ Department of Earth and Planetary Sciences, University of California, 1156 High St., Santa Cruz, CA 95064, USA.
⁹ Department of Earth, Environmental, and Planetary Sciences, Brown University, 324 Brook Street, Providence, RI 02912, USA.
¹⁰ Department of Earth Science, Rice University, 6100 South Main Street, MS-126, Houston, TX 77005-1892, USA.
¹¹ Department of Geology and Geophysics, Texas A&M University, MS 3115 TAMU, College Station, TX 77845, USA.
¹² GEOMAR, Helmholtz Center for Ocean Research, Kiel, Wischhofstrasse 1-3, Kiel 24148, Germany.
¹³ Department of Natural Environmental Science, Faculty of Science, Kochi University, Akebonocyo 2-5-1, Kochi 780-8520, Japan.
¹⁴ Programa de Pós-Graduação em Geologia, Universidade do Vale do Rio dos Sinos, Avenida Unisinos 950, São Leopoldo RS 93.022-000, Brazil.
¹⁵ Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology (AIST), Central 7, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8567, Japan.
¹⁶ School of Earth and Environment, University of Leeds, Leeds LS2 9JT, UK.
¹⁷ College of Earth, Ocean and Atmospheric Sciences, Oregon State University, Ocean Administration Building, 104, 101 SW 26th Street, Corvallis, OR 97331-5503, USA.
¹⁸ College of Oceanography, Hohai University, 1 Xikang Road, Nanjing, Jiangsu Province 210093, P.R. China.
¹⁹ International Ocean Discovery Program, Texas A&M University, College Station, TX 77845, USA.
²⁰ Ecole Nationale Superieure de Geologie-Laboratoire GeoRessources, Universite de Lorraine, 2 rue du Doyen Marcel Roubault, BP 10162, 54505 Vandoeuvre-les-Nancy Cedex, France.
²¹ Energy, CSIRO, 26 Dick Perry Avenue, Kensington 6151, Australia.
²² School of Earth Sciences, Ohio State University, 317 Mendenhall Lab, 125 S. Oval Mall, Columbus, OH 43202, USA.
²³ Department of Geophysics, Colorado School of Mines, 1318 Maple Street, Bldg. 6, Golden, CO 80401, USA.
²⁴ Department of Earth and Atmospheric Sciences, Cornell University, 3126 Snee Hall, Ithaca, NY 14853-1504, USA.
²⁵ Instituto Português do Mar e da Atmosfera, I.P. (IPMA), Rua C ao Aeroporto, 1749-077 Lisboa, Portugal.
²⁶ Institute for Marine-Earth Exploration and Engineering, Japan Agency for Marine-Earth Science and Technology, Yokosuka, Japan.
²⁷ Institute for Geophysics, University of Texas, 10100 Burnet Road, Austin, TX 78758, USA.
²⁸ MARUM Center for Marine Environmental Sciences and Faculty of Geosciences, University of Bremen, Leobener Strasse 8, Bremen 28359, Germany.
²⁹ Disaster Prevention Research Institute, Kyoto University, Gokasyo, Uji, Kyoto 611-0011, Japan.
³⁰ Korea Institute of Geoscience and Mineral Resources (KIGAM), 124 Gwahang-no, Yuseong-gu, Daejeon 305-350, Republic of Korea.
³¹ Marine Geology Research Group, GSJ, AIST Central 7, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8567, Japan.
³² College of Earth Science, Guilin University of Technology, 12 Jian gan Road, Guilin City 541004, P.R. China.
³³ Shanghai Engineering Research Center of Hadal Science and Technology, College of Marine Sciences, Shanghai Ocean University, Shanghai 201306, P.R. China.
³⁴ Geosciences Montpellier Laboratory, Université Montpellier, CC.60, Place E. Bataillon, 34095 Montpellier Cédex 5, France.
³⁵ Department of Earth Sciences/SOEST, University of Hawaii at Manoa, 1680 East-West Road, Honolulu, HI 96822, USA.
³⁶ Department of Earth, Ocean and Ecological Sciences, University of Liverpool, Jane Herdman Building, 4 Brownlow Street, Liverpool L69 3GP, UK.
³⁷ University of Oxford, South Parks Road, Oxford OX1 3AN, UK.
³⁸ Department of Geological Sciences, University of Florida, Gainesville, FL 32611, USA.
³⁹ Department of Geophysics, Banaras Hindu University, Institute of Science, Varanasi Uttar Pradesh 221005, India.
⁴⁰ School of Oceanography, University of Washington, Seattle, WA 98195-7940, USA.
⁴¹ Key Laboratory of Marine Geology and Environment, Chinese Academy of Sciences, Nanhai Road 7, Qingdao, Shandong 266071, P.R. China.
⁴² School of Environmental and Marine Sciences, University of Auckland, Private Bag 92091, Auckland 1142, New Zealand.

Abstract

Slow slip events (SSEs) accommodate a significant proportion of tectonic plate motion at subduction zones, yet little is known about the faults that actually host them. The shallow depth (<2 km) of well-documented SSEs at the Hikurangi subduction zone offshore New Zealand offers a unique opportunity to link geophysical imaging of the subduction zone with direct access to incoming material that represents the megathrust fault rocks hosting slow slip. Two recent International Ocean Discovery Program Expeditions sampled this incoming material before it is entrained immediately down-dip along the shallow plate interface. Drilling results, tied to regional seismic reflection images, reveal heterogeneous lithologies with highly variable physical properties entering the SSE source region. These observations suggest that SSEs and associated slow earthquake phenomena are promoted by lithological, mechanical, and frictional heterogeneity within the fault zone, enhanced by geometric complexity associated with subduction of rough crust.

Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).