Control of internal structure and fluid-migration pathways within the Barbados Ridge décollement zone by strike-slip faulting: Evidence from coherence and three-dimensional seismic amplitude imaging

Research Article| January 01, 2002 Control of internal structure and fluid-migration pathways within the Barbados Ridge décollement zone by strike-slip faulting: Evidence from coherence and three-dimensional seismic amplitude imaging Christopher G. DiLeonardo; Christopher G. DiLeonardo 1Earth Sciences Department, University of California, Santa Cruz, California 95064, USA Search for other works by this author on: GSW Google Scholar J. Casey Moore; J. Casey Moore 1Earth Sciences Department, University of California, Santa Cruz, California 95064, USA Search for other works by this author on: GSW Google Scholar Susan Nissen; Susan Nissen 2Amoco Exploration and Production Technology Group, Tulsa, Oklahoma 74102, USA Search for other works by this author on: GSW Google Scholar Nathan Bangs Nathan Bangs 3Institute of Geophysics, University of Texas, Austin, Texas 78759, USA Search for other works by this author on: GSW Google Scholar GSA Bulletin (2002) 114 (1): 51–63. https://doi.org/10.1130/0016-7606(2002)114<0051:COISAF>2.0.CO;2 Article history received: 11 Nov 1999 rev-recd: 17 Nov 2000 accepted: 25 Jun 2001 first online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share MailTo Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation Christopher G. DiLeonardo, J. Casey Moore, Susan Nissen, Nathan Bangs; Control of internal structure and fluid-migration pathways within the Barbados Ridge décollement zone by strike-slip faulting: Evidence from coherence and three-dimensional seismic amplitude imaging. GSA Bulletin 2002;; 114 (1): 51–63. doi: https://doi.org/10.1130/0016-7606(2002)114<0051:COISAF>2.0.CO;2 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 SocietyGSA Bulletin Search Advanced Search Abstract The application of three-dimensional seismic reflection and coherence imaging to the study of the décollement zone of the Barbados Ridge accretionary complex has provided new insights into the relationships among internal structure, fluid flow, and previously unrecognized strike-slip faulting. Combined coherence and seismic amplitude imaging of the décollement zone reveal anomalous northeast-trending lineaments parallel to and abutting zones of high- amplitude, negative-polarity reflections. Analysis of these lineaments shows them to be penetrative structures dipping southeast with apparent reverse dip-slip offset. Isopach mapping of the accretionary wedge indicates significant right-lateral displacement across these structures. These faults apparently channel fluid flow within the décollement zone, and the prominent northeast- trending conduits so formed are readily visible as high-amplitude, negative-polarity reflections. Additionally, north-northeast– trending zones of variable coherence and high positive amplitude are inferred barriers to up-structure fluid-migration pathways.Movement along strike-slip structures probably alternates with displacement along the décollement zone. Northeast- trending strike-slip faults extend for >13 km, crossing the length of the survey area and into the incoming oceanic plate. Active arc-oblique strike-slip faulting of the décollement zone beneath the Barbados Ridge accretionary wedge implies a stress regime in that σ1 is fixed and σ2 and σ3 either transpose with time or are nearly equal. This state of stress may be a common occurrence in forearc tectonism and may have led to the formation of many, as yet unrecognized, arc-oblique strike-slip faults at convergent margins. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.