Plate Boundaries

Web Page Research & Design

Minnha Tran and Paris Rogers

Through various measurments and studies of the Northern Caribbean such as, GPS, seismic measure and plate tectonics. Leroy tells us that, “Jamaica lies on a stretch of plate that connects to the “Gon’ave–Caribbean Plate Boundary.(see figures 1&2) (Leroy et.al 1996)  He goes on to tell us that, “Along the 1100-km-long stretch of this plate connects the Cayman spreading center to faults in central Hispaniola, Caribbean–North America motion is partitioned between the Oriente faults, which follows the northern boundary of the Cayman Trough along much of its length.” (See Fig. 1).

                                                             

Again Leroy tells us about the northwestern part of Jamaica and there lays the Walton–Enriquillo–Plantain Garden fault zone, which together follows the southern boundary of the Cayman Trough. He states, “This boundary straddles many and possibly all the faults that accommodate this plate motion.” (Leroy et.al 1996)

            

Jamaica’s history is known for its destructive earthquakes and seismic activity.(Wiggins-Gandison 2001)  Because of this activity faults are exposed and considered active. Leroy states,“but the rate and distribution of the fault sops are known only from geological studies of the island and the mapping of offshore faults.”  (Leroy et al 1996)

 

In Figure 1. Leroy displays the, “ (a) Location map and tectonic setting for Gonave microplate and north central Caribbean. Arrows show Caribbean–North American Plate motion predicted by DeMets et al. (2006) model. Parenthetical numerals indicate rate in mm yr−1. Figure 2 (b) 2-min seafloor bathymetry and land topography from Sandwell & Smith (1997)”. (Leroy et al. 1996)

            

 In Figure 3. Leroy displays, “ (a) Fault and GPS station locations. (b) The Jamaica Seismograph Network(triangles) and microearthquakes detected by four or more JSN stations during 1998-2004 (circles).  In this graph only earthquakes with a magnitude of 2.0  or higher are shown. (c)  Locations of GPS stations (red) and  potentially active major faults.” (Leroy et al. 1996)

 

Leroy also tells us, “Jamaica is part of the uplifted Nicaraguan Rise, which is a submarine volcanic plateau that extends southwest of the Cayman Trough.  Here limestone and rock formations of older rocks are surrounded by younger rocks. These rocks dating from the end of the Mesozoic era are exposed at the surface and are offset by many faults and some with present activity.  The islands primary faults the Plantain Garden, Duanvale, Rio Minho-Crawl River and the South costal faults (see fig 3) are connected by a series of NNW-striking faults that are alleged to transfer motion between them.  You will find it most prominent in the Blue Mountains of eastern Jamaica.” (Leroy et.al 1996)