Kinematics of the North American–Caribbean-Cocos plates in Central America from new GPS measurements across the Polochic-Motagua fault system

The Polochic‐Motagua strike‐slip fault system in Guatemala marks the on‐land plate boundary between the North American (NA) and the Caribbean (CA) plates. GPS observations in 1999 and 2003 show that the far‐field velocity across the system (NA‐CA relative velocity) is ∼20 mm/yr. This is significantl...

Full description

Saved in:

Bibliographic Details
Published in:	Geophysical research letters Vol. 33; no. 19; pp. L19309 - n/a
Main Authors:	Lyon-Caen, H., Barrier, E., Lasserre, C., Franco, A., Arzu, I., Chiquin, L., Chiquin, M., Duquesnoy, T., Flores, O., Galicia, O., Luna, J., Molina, E., Porras, O., Requena, J., Robles, V., Romero, J., Wolf, R.
Format:	Journal Article
Language:	English
Published:	Washington, DC American Geophysical Union 01-10-2006 Blackwell Publishing Ltd
Subjects:	Continental tectonics Earth Sciences Earth, ocean, space Exact sciences and technology Geodesy and Gravity Geophysics Marine Plate motions present and recent results Satellite geodesy Sciences of the Universe Seismic cycle related deformations Tectonics Tectonophysics Motagua Fault Guatemala Cocos Plate North American Plate Caribbean Plate Central America models extension volcanic arcs kinematics aluminum Velocity distribution Global Positioning System far-field strike-slip faults slip rates depth slip plate boundaries Cocos Plate triple junctions
Online Access:	Get full text
Tags:	Add Tag No Tags, Be the first to tag this record!

Description
Summary:	The Polochic‐Motagua strike‐slip fault system in Guatemala marks the on‐land plate boundary between the North American (NA) and the Caribbean (CA) plates. GPS observations in 1999 and 2003 show that the far‐field velocity across the system (NA‐CA relative velocity) is ∼20 mm/yr. This is significantly higher than the NUVEL‐1A velocity but is consistent with the GPS based CA‐NA velocity proposed by DeMets et al. (2000). The observations are modeled by a fault centered on the Motagua fault, locked at a depth of 20 km, with a slip‐rate decreasing from eastern to central Guatemala from 20 to 12 mm/yr towards the NA‐CA‐Cocos triple junction. This decrease is accommodated by ∼8 mm/yr of E‐W extension in the westernmost part of CA south of the Motagua fault. About 10 mm/yr of dextral slip is observed across the Mid‐American Volcanic Arc. The NA‐CA‐Cocos triple junction is thus a complex, ∼400 km‐wide wedge‐shaped area.
Bibliography:	ark:/67375/WNG-FHW5HDS5-3 ArticleID:2006GL027694 istex:303BE1B9704465E76D35AA9353494E525A68709E ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23
ISSN:	0094-8276 1944-8007
DOI:	10.1029/2006GL027694