Portal de Periódicos da CAPES

Precise Locations for Intermediate‐Depth Earthquakes in the Cauca Cluster, Colombia

2017; Seismological Society of America; Volume: 107; Issue: 6 Linguagem: Inglês

10.1785/0120170127

1943-3573

Ying Chang, L. M. Warren, G. A. Prieto,

Earthquake Detection and Analysis

Research Article| October 31, 2017 Precise Locations for Intermediate‐Depth Earthquakes in the Cauca Cluster, Colombia Ying Chang; Ying Chang aDepartment of Earth and Atmospheric Sciences, Saint Louis University, 3642 Lindell Boulevard, Saint Louis, Missouri 63108, ychang14@slu.edu Search for other works by this author on: GSW Google Scholar Linda M. Warren; Linda M. Warren aDepartment of Earth and Atmospheric Sciences, Saint Louis University, 3642 Lindell Boulevard, Saint Louis, Missouri 63108, ychang14@slu.edu Search for other works by this author on: GSW Google Scholar Germán A. Prieto Germán A. Prieto bDepartamento de Geociencias, Facultad de Ciencias, Universidad Nacional de Colombia ‐ Sede Bogotá, Edificio Manuel Ancizar Oficina 206, Carrera 30 Number 45 – 03, Bogotá, Colombia Search for other works by this author on: GSW Google Scholar Author and Article Information Ying Chang aDepartment of Earth and Atmospheric Sciences, Saint Louis University, 3642 Lindell Boulevard, Saint Louis, Missouri 63108, ychang14@slu.edu Linda M. Warren aDepartment of Earth and Atmospheric Sciences, Saint Louis University, 3642 Lindell Boulevard, Saint Louis, Missouri 63108, ychang14@slu.edu Germán A. Prieto bDepartamento de Geociencias, Facultad de Ciencias, Universidad Nacional de Colombia ‐ Sede Bogotá, Edificio Manuel Ancizar Oficina 206, Carrera 30 Number 45 – 03, Bogotá, Colombia Publisher: Seismological Society of America First Online: 31 Oct 2017 Online Issn: 1943-3573 Print Issn: 0037-1106 Bulletin of the Seismological Society of America (2017) 107 (6): 2649–2663. https://doi.org/10.1785/0120170127 Article history First Online: 31 Oct 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Ying Chang, Linda M. Warren, Germán A. Prieto; Precise Locations for Intermediate‐Depth Earthquakes in the Cauca Cluster, Colombia. Bulletin of the Seismological Society of America 2017;; 107 (6): 2649–2663. doi: https://doi.org/10.1785/0120170127 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 SocietyBulletin of the Seismological Society of America Search Advanced Search Abstract In subducting slabs, a high seismicity rate in a concentrated volume (an earthquake nest) is often associated with geometric complexities such as slab detachment, tearing, or contortions. In Colombia, the Cauca cluster has a high rate of intermediate‐depth earthquakes between 3.5°–5.5° N and 77.0°–75.3° W. From January 2010 to March 2014, the Colombian National Seismic Network reports 433 earthquakes in the cluster at depths of 50–200 km with local magnitudes ranging from ML 2.0 to 4.7. We determine precise relative locations of the intermediate‐depth earthquakes in the cluster and investigate the cause of the cluster by estimating its geometry from earthquake relocations. Earthquake relocations show a continuous 20‐km‐thick intraslab seismic zone dipping at 33°–43°, with the dip angle increasing to the south. In addition, earthquakes locate in two isolated fingers that extend 30–40 km normal to and above the slab. The depth and vertical separation of the earthquakes in the two fingers indicate that the two fingers do not belong to the intraslab seismic zone or the overriding crustal seismic zone and instead are in the mantle wedge. Changes in the velocity model, starting earthquake locations, or the precision of the arrival picks do not lead to significant changes in the relative locations. The Cauca cluster, with earthquakes located in and above a continuous slab, appears to have a different mechanism than previously studied earthquake nests. The high seismicity rate in the cluster may, instead, correspond to high volumes of dehydrated fluid. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.