Regional Effects
of the Cuban Arc-Continent
Collision on Structure, Stratigraphy and Hydrocarbons in the Deepwater,
Southeastern Gulf of Mexico
The deepwater area of the southeastern Gulf of Mexico
(SEGOM) has basinal water depths ranging from 500 to 2000 meters and is
subdivided into the maritime zones of the United States, Mexico and Cuba. This
presentation reviews evidence from offshore, subsurface data for a latest
Cretaceous-Paleogene forebulge and terminal collision between the Cuban arc at
the leading edge of the Caribbean plate and thinned continental crust in the SEGOM maritime zones. During the late Jurassic, the SEGOM was a broad zone of
rifting between North and South America that included deposition of Kimmeridgian-Tithonian marine shale and carbonate that forms excellent,
widespread source
rocks in this and other parts of the circum-Atlantic.
Potential reservoirs overlying these
source
rocks include upper Jurassic to
Cretaceous Cretaceous, deepwater clastic and carbonate rocks deposited in the
passive margin phase that followed the earlier Jurassic rift and continental
separation phase. Interpretations of seismic lines and well subsidence historys
of DSDP wells drilled in the southeastern Gulf of Mexico show an abrupt shallowing of these passive margin rocks during the latest Cretaceous
associated with the formation of a prominent, east-west trending arch north of
Cuba. We interpret this feature as a tectonically-controlled forebulge in
thinned continental crust of North America that culminated in the formation of
an extensive, late Paleocene unconformity seen in offshore wells and the
creation of a variety of potential structural and stratigraphic traps. Bending
of the southern edge of North America created a foreland basin filled with Paleogene clastic sediments derived from the uplifted area of Cuba and onlapping the forebulge north of the collision zone. A major
point
is that this forebulge is a major regional feature that extends as
far
west at the Yucatan
Peninsula and as
far
east as the Florida Keys. Following collision, the forebulge and foreland basin subsided rapidly and was eroded during the later
Cenozoic by the Gulf Stream passing eastward from the SEGOM into the Atlantic.
AAPG Search and Discovery Article #90142 © 2012 AAPG Annual Convention and Exhibition, April 22-25, 2012, Long Beach, California