HR: 09:00h
AN: S21C-05    [Abstracts]
TI: Fault Structure Along the North America-Caribbean Plate Boundary in the Dominican Republic
AU: * Pulliam, J
EM: jay@ig.utexas.edu
AF: Institute for Geophysics, UT Austin, 4412 Spicewood Springs Road, Building 600, Austin, TX 78759 United States
AU: * Pulliam, J
EM: jay@ig.utexas.edu
AF: Puerto Rico Seismic Network, Dept. of Geology, Univ. of Puerto Rico at Mayaguez, P.O. Box 9017, Mayaguez, PR 00680 United States
AU: Ocasio-Campos, D
EM: denisse@midas.uprm.edu
AF: Puerto Rico Seismic Network, Dept. of Geology, Univ. of Puerto Rico at Mayaguez, P.O. Box 9017, Mayaguez, PR 00680 United States
AU: Huerfano-Moreno, V
EM: victor@midas.uprm.edu
AF: Puerto Rico Seismic Network, Dept. of Geology, Univ. of Puerto Rico at Mayaguez, P.O. Box 9017, Mayaguez, PR 00680 United States
AU: von Hillebrandt-Andrade, C
EM: christa@midas.uprm.edu
AF: Puerto Rico Seismic Network, Dept. of Geology, Univ. of Puerto Rico at Mayaguez, P.O. Box 9017, Mayaguez, PR 00680 United States
AU: Camacho, I
EM: ivelisse@midas.uprm.edu
AF: Puerto Rico Seismic Network, Dept. of Geology, Univ. of Puerto Rico at Mayaguez, P.O. Box 9017, Mayaguez, PR 00680 United States
AU: Odonel-Gomez, L
EM: lgomez@verizon.net.do
AF: Instituto de Recursos Hidraulicos, Av. Jiménez de Moya, Centro Los Héroes, Santo Domingo, 00000 Dominican Republic
AU: Payero, J
EM: jpayero@tricom.net
AF: Instituto Sismologico Universitario de la Universidad Autonoma Santo Domingo, Apto. Postal 1335, Ciudad Universitario, Santo Domingo, 00000 Dominican Republic
AB: The Northern Caribbean Plate Boundary Zone is a complex region that has been modified extensively by the relative eastward movement of the Caribbean Plate and the plate's impact with the buoyant Bahama carbonate platform (see Figure). The results include extensive subduction of oceanic crust belonging to the North American Plate, a broad zone of deformation to accommodate strain, the development of several new transform and normal faults to relieve stress after collisions, the formation and rotation of microplates, and the rearrangement and aggregation of crustal fragments into new islands. On 22 September 2003, a large (mW=6.5) earthquake struck the Dominican Republic, causing widespread damage that included partially collapsed buildings and bridges in the cities of Santiago and Puerto Plata and landslides in the mountainous outlying areas. Aftershocks reaching mW=5.1 followed for weeks afterward. This earthquake sequence is the strongest to affect the Dominican Republic since a series of powerful thrust events, including five earthquakes ranging in magnitude from 7.1 to 8.1, occurred between 1943 and 1953. Prior to 1943, significant earthquakes occurred in 1564 (in which the city of Santiago was destroyed), 1783, 1842, 1887, and 1897. Following the 2003 Puerto Plata main shock we deployed 10 broadband seismographs borrowed from IRIS' PASSCAL Instrument Center around the aftershock zone for a period of two months and analyzed the data jointly with data from two permanent seismic networks in the DR. Analyses included estimating a new 1D model of earth structure, re-locating more than 300 aftershocks, producing a 3D tomographic model of the fault zone from phase arrivals, and computing focal mechanisms. We will report the results of these analyses and their implications for regional structure and processes.
DE: 7230 Seismicity and tectonics (1207, 1217, 1240, 1242)
DE: 7240 Subduction zones (1207, 1219, 1240)
DE: 7250 Transform faults
DE: 7299 General or miscellaneous
SC: Seismology [S]
MN: Fall Meeting 2005