Evolution of shallow, crustal thermal structure from subduction to collision: An example from Taiwan

Research Article| May 01, 2008 Evolution of shallow, crustal thermal structure from subduction to collision: An example from Taiwan Wu-Cheng Chi; Wu-Cheng Chi † 1Institute of Earth Sciences, Academia Sinica 128 Sec 2 Academia Road, Nankang, Taipei, Taiwan, ROC †E-mail:chi@earth.sinica.edu.tw Search for other works by this author on: GSW Google Scholar Donald L. Reed Donald L. Reed * 2Department of Geology, San Jose State University, One Washington Square, San Jose, California 95192-0102, USA *E-mail:dreed@geosun.sjsu.edu Search for other works by this author on: GSW Google Scholar Author and Article Information Wu-Cheng Chi † 1Institute of Earth Sciences, Academia Sinica 128 Sec 2 Academia Road, Nankang, Taipei, Taiwan, ROC Donald L. Reed * 2Department of Geology, San Jose State University, One Washington Square, San Jose, California 95192-0102, USA †E-mail:chi@earth.sinica.edu.tw *E-mail:dreed@geosun.sjsu.edu Publisher: Geological Society of America Received: 27 Feb 2007 Revision Received: 02 Nov 2007 Accepted: 02 Nov 2007 First Online: 02 Mar 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 © 2008 Geological Society of America GSA Bulletin (2008) 120 (5-6): 679–690. https://doi.org/10.1130/B26210.1 Article history Received: 27 Feb 2007 Revision Received: 02 Nov 2007 Accepted: 02 Nov 2007 First Online: 02 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 Wu-Cheng Chi, Donald L. Reed; Evolution of shallow, crustal thermal structure from subduction to collision: An example from Taiwan. GSA Bulletin 2008;; 120 (5-6): 679–690. doi: https://doi.org/10.1130/B26210.1 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 We study crustal thermal evolution by examining heat flow patterns along a convergent boundary from a young subduction zone to a more structurally mature collision zone. More than 8000 km of seismic profiles covering an offshore region of 45,000 km2 in southern Taiwan show widespread bottom-simulating reflectors (BSRs). We derived 1107 BSR-based heat flows before combining 42 additional, published, offshore thermal probe data and 86 on-land heat flow data to document the shallow forearc thermal structures from the subduction zone to the collision zone. In the subduction zone, the geothermal gradient ranges mostly within 30–80 °C/km, and decreases toward the arc due to slab cooling, intensive dewatering at the toe, sediment blanketing, topographic effects, and other processes. The geothermal gradient ranges mostly from 30 to 90 °C/km in the collision zone, and increases, instead of decreases, toward the arc, possibly caused by exhumation, erosion, topographically induced ground-water circulation, and some upper mantle processes related to collision. Heat flow in the collision zone ranges from 80 to 250 mW/m2. The high heat flow in the collision zone correlates with a shallower seismicity zone and high seismic attenuation, while the lower heat flow in the subduction zone might allow the earthquakes to rupture to greater depth. The heat flow increases along the topographic high from subduction to collision zone due to increasing geothermal gradients and higher thermal conductivities of the exhumed basement rocks. This heat flow variation may generate an artificial exhumation rate pattern, if a conventional 30 °C/km geothermal gradient was used in fission-track studies. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.