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units (Figs. 1B and 2; Iturralde-Vinent, 2011). Many of these (Iturralde-Vinent, 2013; Iturralde-Vinent et al., 2008; van
units were partially subducted, metamorphosed, and exhumed.
These lithotectonic associations are briefly summarized in the
following sections.
NORTH AMERICAN (NOAM) ACCRETED DEPOSITS
North American igneous rocks and sediments originally
formed along the Yucatan and Bahamas passive margins and else-
where in the Proto-Caribbean basin. These units now crop out as
juxtaposed fold-and-thrust belts of the Guaniguanico terrane, the (3) the Escambray greenschist to eclogite facies complex with
Northern Foldbelt, and the metamorphic Caribeana terranes
(Fig. 1B).
Guaniguanico Terrane
This terrane includes Early(?) Jurassic to latest Cretaceous
passive margin siliciclastics, marine basalts, limestone, shale,
and chert that record the origin and evolution of the Proto-
Caribbean seaway (Fig. 2; Pszczółkowski, 1999; Iturralde-
Vinent, 2011). These rocks are overlain by Paleocene to Lower
Eocene synorogenic foredeep sedimentary rocks, including
limestones, flysch, and olistostrome deposits. This ensemble was
overthrust by ophiolitic and volcanic arc units (Bralower and
Iturralde-Vinent, 1997).
Northern Foldbelt
This belt preserves the southern edge of the Mesozoic Florida-
Bahamas platform deposits (Figs. 1B and 2; Meyerhoff and
Hatten, 1974). The Northern Foldbelt and the Guaniguanico
Terrane share similar Late Jurassic and Cretaceous Proto-
Caribbean marine deposits. Between Paleocene and early Upper
Eocene time, a forebulge and synorogenic foredeep developed
with olistostrome, flysch, and carbonate deposition ahead of the
leading edge of CARIB; extensive overthrusting also occurred
GSA TODAY | OCTOBER 2016
Figure 2. Generalized tectonic-stratigraphic chart of Cuba modified from Iturralde-Vinent (2011). Under “volcanic arcs,” abbreviations refer to island arc tholeiite
(IAT), alkaline suites (AL), and calc-alkaline suites (CALC). KTB channel refers to a deep erosional channel cut due to the Cretaceous-Tertiary boundary mass
flows from the platform margins due to the impact.
6
Hinsbergen et al., 2009).
Caribeana Metamorphic Terranes
These terranes comprise Proto-Caribbean Jurassic-Cretaceous
passive margin and oceanic protoliths (Figs. 1B and 2) that were
subducted and accreted to Cuba ~75–60 m.y. ago (García-Casco
et al., 2008). Caribeana is represented in Cuba by (1) the Cangre
glaucophane-bearing terrane; (2) the Pinos metamorphic terrane;
inverted metamorphic structure; and (4) the Asunción lawsonite
and glaucophane-bearing terrane (Figs. 1B and 2; Somin and
Millán, 1981; García-Casco et al., 2008; Despaigne et al., 2016).
CARIBBEAN PLATE
CARIB allochthonous units are fragments of Pacific oceanic
lithosphere that migrated into their present positions during
Cretaceous time. An integrated geologic (Whattam and Stern,
2015) and geodynamic (Gerya et al., 2015) case has been made
that Caribbean plate formation began when the Galapagos mantle
plume head impinged on the Proto-Caribbean seaway in Early
Cretaceous time. Alternatively, Pindell et al. (2012) proposed
that onset of subduction at ca. 135 Ma occurred along an inter-
American transform fault with no influence of plume head.
The Greater Antilles subduction zone along the leading edge of
the Caribbean plate was responsible for the subduction of at
least 1500 km of Proto-Caribbean and NOAM lithosphere in a
SW-dipping intra-oceanic subduction zone (Figs. 1B and 2).
The following CARIB units can be distinguished in Cuba.
Ophiolites and Ophiolitic Mélange
These rocks outcrop discontinuously for more than 1000 km
along the northern margin of Cuba. They were obducted onto the