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The timing of deformation and landscape evolution along the
Central Range fault system, Trinidad
Scott Giorgis, Department of Geological Sciences, SUNY Geneseo, Geneseo, NY 14454, [email protected]
Central Range Fault System: High precision GPS measurements collected by previous workers in the
Central Range indicate they are the focus of slip between the Caribbean plate to the north and the South
American plate the the south. The low, rolling topography of the Central Range Mountains are likely due
to tectonic contraction within this active fault zone. One of the goals of this project is to use gravity data to
determine if there is a crustal root underlying the Central Range, and if so its shape and magnitude.
Shaded relief digital
elevation model of
Trinidad. The Central
Range fault system follows
the low relief mountain range
in central Trinidad. Each dot
marks the location of a
gravity station provided by
the National Geospatial
Intelligence Agency.
Uncorrected gravity map of
Trinidad. Hot colors (red)
indicate gravity highs and cool
colors (blue) indicate gravity
lows. The gradient from
gravity low in the south to
gravity high in the north
reflects the transition from less
dense South American
continental crust to more
dense Caribbean oceanic
crust.
Corrected Bouguer gravity map of Trinidad.
Application of the standard Bouguer corrections, the
terrane correction, and removal of the regional gradient
reveals the presence of a small gravity low in the
Central Range of Trinidad. The presence of a crustal
root is suggested by the overlap between the Central
Range topography and the shape of the gravity low.
With these data, we hope to be able to model the size
and shape of the crustal root using standard threedimensional inversion techniques.