Timing and Evolution of Cretaceous Island Arc Magmatism in Central Cuba: Implications for the History of Arc Systems in the Northwestern Caribbean

Abstract

SHRIMP and conventional zircon dating place temporal constraints on the evolution of the Cretaceous Volcanic Arc system in central Cuba. The arc has a consistent stratigraphy across strike, with the oldest and deepest rocks in the south (in tectonic contact with the ∼5-10-km-wide Mabujina Amphibolite Complex [MAC]) and younger rocks in the north. The MAC is thought to represent the deepest exposed section of the Cretaceous Volcanic Arc and its oceanic basement in Cuba. We undertook a single zircon geochronological study of five gneisses and two amphibolites from the MAC and seven rocks from the Manicaragua Batholith, which intrudes both the MAC and the Cretaceous Volcanic Arc. A SHRIMP zircon age of Ma for a trondhjemitic orthogneiss (MAC) from the Jicaya River 132.9 ‫ע‬ 1.4 dates the oldest phase of granitoid magmatism in this area and the entire Caribbean (Antillean) region. A tonalitic gneiss collected near the previous sample yielded an age of Ma, and a further tonalitic gneiss had an age 123.9 ‫ע‬ 0.6 of Ma, with one inherited zircon at Ma. Two trondhjemitic orthogneisses from the central part 112 ‫ע‬ 2.1 1045 ‫ע‬ 17 of the MAC yielded ages of and Ma, whereas two amphibolites from the eastern part of the 93.8 ‫ע‬ 0.5 92.8 ‫ע‬ 0.7 complex provided similar ages of ca. 93 Ma and zircon inheritance at 315, 471, 903, and 1059 Ma. Two weakly foliated Manicaragua granitoids from the eastern part of the massif provided ages of and Ma, whereas 89.3 ‫ע‬ 0.45 87.2 ‫ע‬ 1.2 five unfoliated granitoid samples from the central and eastern part of the massif yielded ages of , 88.7 ‫ע‬ 0.7 , , , and Ma. Our age data support the view that the Mabujina Protholiths 87.4 ‫ע‬ 1.3 87.0 ‫ע‬ 0.6 84.2 ‫ע‬ 0.8 83.1 ‫ע‬ 0.8 are exotic and formed somewhere NNW along strike of the nonmetamorphosed Cuban arc since pre-Middle Hauterivian time (before ∼133 Ma). The MAC became part of the Cuban Volcanic Arc during the Turonian (ca. 90-93 Ma), when it was intruded by plutonic rocks of the Manicaragua Batholith (Turonian-Campanian; ca. 89-83 Ma). The geology and geochronology of central Cuba do not support the idea of a polarity reversal event at any stage of the Cretaceous Arc-building process. Because most of our dated samples come from the narrow Mabujina Belt, the polarity reversal model would imply that the axis of a newly developing arc (with opposite polarity) would spatially coincide with the older arc, which appears unlikely. Inherited Precambrian and Palaeozoic zircons in the MAC granitic rocks (similar to inherited zircon populations in the Guerrero terrane from central-western Mexico) suggest a Neocomian proximal setting close to a cratonic area (probably SW Mexico/Maya Block) for the protolith of the MAC relative to the synchronous Primitive Island Arc of central Cuba.

Paleostress evolution during the exhumation of high-P marbles, Samaná Complex, northern Hispaniola

“…El modelo tectónico evolutivo que proponen estos autores sobre la base de datos P-T-t precisos y teniendo en cuenta las características estructurales de los complejos exhumados a lo largo del margen N del arco caribeño (EscuderViruete et al, 2013) es un modelo de colisión polifási-co en el que la mélange serpentinítica se habría originado en el canal de subducción intraoceánico durante la colisión arco-arco del Cretácico Superior, mientras que el complejo de Samaná representa el estadio de colisión posterior arco-continente entre el Paleoceno y el Oligoceno. Esta colisión polifásica es consistente con las edades de deformación del margen N caribeño (Blein et al, 2003;Krebs et al, 2008;Neill et al, 2010;Rojas-Agramonte et al, 2011;Escuder-Viruete et al, 2011c) e indica que la colisión fue ligeramente oblicua, porque la deformación migró hacia el NE/ENE con el tiempo (Escuder-Viruete et al, 2013). Las claves para entender el proceso de exhumación del complejo de Samaná, en el que se combinan las características del modelo clásico de Jolivet et al (1994) con la deformación impuesta en el canal de subducción durante la exhumación (entre los estadios M1 y M2) está en el registro microtectónico de la foliación S2.…”

The geology of Cuba: A brief overview and synthesis

“…Arc-related granitoid plutons range in age from ca. 89-83 Ma in the Santa Clara province (westcentral Cuba) and 104-75 Ma in Camagüey province (east-central Cuba) (Hall et al, 2004;Rojas-Agramonte et al, 2011).…”

Mineralogy, geochemistry and sulfur isotope characterization of Cerro de Maimón (Dominican Republic), San Fernando and Antonio (Cuba) lower Cretaceous VMS deposits: Formation during subduction initiation of the proto-Caribbean lithosphere within a fore-arc

“…135 Ma (Rojas-Agramonte et al, 2011;Pindell et al, 2012, and references therein). Subduction and related arc magmatism ceased in Hispaniola and Cuba in the latest Cretaceous-earliest Tertiary as a result of volcanic arc-Caribeana terrane collision (García-Casco et al, 2008), though subduction and volcanism renewed in Hispaniola and eastern Cuba until the Eocene when the final collision of the arc and the Bahamas Platform took place (Lewis and A C C E P T E D M A N U S C R I P T ACCEPTED MANUSCRIPT Draper, 1990;Mann et al, 1991;Rojas-Agramonte et al, 2006, 2008Boschman et al, 2014).…”

“…Formation is the oldest unit of the Greater Antilles arc in Cuba (Díaz de Villalvilla et al, 1994Kerr et al, 1999;Blein et al, 2002;Rojas-Agramonte et al, 2011). The Los Pasos Formation is only locally deformed by folding, and is not metamorphosed (Díaz de Villalvilla et al, 1994).…”

“…1C). The Los Pasos Formation forms the southern limb of a synformal structure together with the other arc sequences (Iturralde-Vinent, 1998 as the metamorphosed roots of the island arc and its oceanic sole (Millán, 1996) or as an exotic volcanic arc terrane not related to the Greater Antilles arc (Blein et al, 2002;Rojas-Agramonte et al, 2011 …”