Coseismic Ground Rupture of the 15 October 2013 Magnitude (MW) 7.2 Bohol Earthquake, Bohol Island, Central Philippines. Issue 8 (1st August 2019)

• Record Type: Journal Article
• Authors: Rimando, Jeremy M.; Aurelio, Mario A.; Dianala, John Dale B.; Taguibao, Kristine Joy L.; Agustin, Krissen Marie C.; Berador, Al Emil G.; Vasquez, Adriann A.
• Is Part Of: Tectonics. Volume 38:Issue 8(2019)
• Page Start: 2558
• Page End: 2580
• Publication Date: 2019-08-01
• Subjects: 2013 Bohol earthquake -- North Bohol Fault -- coseismic ground rupture -- reverse fault -- trenching -- fold‐and‐thrust belt; Geology, Structural -- Periodicals; 551.8
• DOI: 10.1029/2019TC005503
• Languages: English
• ISSNs: 0278-7407

Abstract

Abstract: The 15 October 2013 magnitude ( M W ) 7.2 Bohol earthquake produced an ~50‐km‐long, ~12‐km‐wide northeast trending zone of uplift with an ~8‐km‐long discontinuous ground rupture indicating predominantly reverse‐slip movement on a southeast dipping fault. Documentation of the nearly continuous northern terminus of the 2013 Bohol earthquake ground rupture revealed its association to preexisting scarps of the previously unmapped, Quaternary‐active North Bohol Fault. Trenching across the rupture at four sites not only reveals the geometry and kinematics of the fault but also shows at least one or two pre‐2013 surface rupturing events. Onshore geologic mapping and offshore seismic reflection profiles demonstrate the presence of an island‐wide, northeast‐southwest trending fold‐and‐thrust belt through which deformation related to the regional shortening across the Visayan Sea Basin in the central Philippines is likely distributed. Key Points: There is an ~8‐km‐long discontinuous ground rupture within an ~50‐km‐long, ~12‐km‐wide zone of uplift based on SAR pixel offset analysis Trenching reveals NE striking, SE dipping fault strands of the NBF that represent at least one or two pre‐2013 surface rupturing events