ABSTRACT
The Lucea Inlier exposes a Santonian to Campanian 4 km + thick
sequence of shale-siltstone, resedimented volcaniclastics, lenses
of shallow-water limestone, micritic limestone, pebbly mudstone
and sandy pebble to boulder conglomerate. Clastics were deposited
by a variety of gravity flow mechanisms. Petrographically
sandstones are lithic or feldspathic arenites and contain only
very small amounts of detrital quartz. Structurally the inlier is
characterized by simple, open, east-west trending folds. A spaced,
vertical axial-planar cleavage is developed in shales and fine
siltstones. Two major east-west trending left-lateral fault zones,
the Fat Hog Quarter and Maryland faults, cut the inlier into three
blocks, northern, central and southern. The basal part of the
sequence has been subjected to a prehnite-pumpellyite
metamorphism.
The rocks of the Lucea Inlier are interpreted to represent a shelf
to basin sequence within an upper slope basin of a Cretaceous
intraoceanic arc trench system. Detritus shed from the arc was
funneled down submarine canyons feeding a submarine fan complex.
Between canyon heads, shoal areas fringing volcanic islands
locally accumulated bioclastic, reef-type limestone.
The geology of the northern Caribbean plate boundary records a
complex array of Cretaceous to Eocene arc-trench systems that has
been modified by Cenozoic left-lateral slip along the Oriente and
Swan transforms.
Ridge related north-south lineated topography of the Cayman Trough
suggests that a minimum of 720 km of left-lateral movement has
occurred between the North American and Caribbean plate since
approximately Oligocene times. Presently active northwest,
northeast and east-west trending structures within Jamaica are
interpreted as being of compressional, extensional and strike-slip
origin, respectively, and are thought to be related to Recent
left-lateral slip along the northern Caribbean plate boundary.
Grippi, J., 1978. Geology of the Lucea Inlier, Western Jamaica.
Unpublished MSc. thesis, State University of New York at Albany.
183pp., +x.; 6 folded plates (maps)
University at Albany Science Library call number: SCIENCE
Oversize (*) QE 224 G63X
MS thesis (scanned text pdf - 23.5MB)
Plate 1 - Geologic
Map - Lucea Inlier, Western Jamaica
(uncoloured geological map;
scale 1:15,840) - pdf file 16 MB
Plate 1A - Stratigraphic
columns of the Central Block - Lucea Inlier, Western Jamaica
(scale 1:2500)
Plate 1B - Geologic
cross sections - Lucea Inlier, Western Jamaica
(uncoloured; scale 1:15,840)
Plate 2 - Geologic
Map - Cascade-Maryland area - Lucea Inlier, Western Jamaica
(uncoloured geological map;
scale 1:12,500)
Plate 2A - Stratigraphic
columns of the Cash Hill Anticline - Lucea Inlier, Western
Jamaica
(scale 1:3000)
Plate 2B - Geologic
cross sections - Cascade-Maryland area - Lucea Inlier, Western
Jamaica
(uncoloured; scale 1:12,500)
Return to MS Theses completed in
the Geological Sciences Program, University at Albany