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| Some tectonic activity extended into the [[Neocomian]] (132 Ma; see Figure 27), possibly associated with the rifting, and uplifted blocks south of the Yaguajay* belt. The result was denudation of previously deposited sediments as indicated by northward shedding of carbonate clastics ([[Sabanilla Fromation|Sabanilla* Formation]]), a southward increase in basement exposures (La Rana, Tres Guanos, Rancho Veloz), and deposition of the [[Jobosi]]* arkosic conglomerate. This basement could have been derived from a continental block, here named the La Rana block (after the best exposures) and similar to the Maya or Chortis blocks, that was overridden by later nappes. | | Some tectonic activity extended into the [[Neocomian]] (132 Ma; see Figure 27), possibly associated with the rifting, and uplifted blocks south of the Yaguajay* belt. The result was denudation of previously deposited sediments as indicated by northward shedding of carbonate clastics ([[Sabanilla Fromation|Sabanilla* Formation]]), a southward increase in basement exposures (La Rana, Tres Guanos, Rancho Veloz), and deposition of the [[Jobosi]]* arkosic conglomerate. This basement could have been derived from a continental block, here named the La Rana block (after the best exposures) and similar to the Maya or Chortis blocks, that was overridden by later nappes. |
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− | In central Cuba, the Upper Jurassic and Neocomian beds were only partially eroded. In western Cuba, shallow-bank carbonates, similar to those of the [[Vinas Group|Vinas* Group]], accumulated atop the La Rana granodiorite [http://en.wikipedia.org/wiki/Horst_%28geology%29 horst] and formed the Guajaibon–Sierra Azul belt. South of the La Rana basement horst, deep-water limestones of the Mayari, Collantes, and Cobrito Formations were deposited and preserved. | + | In central Cuba, the Upper Jurassic and Neocomian beds were only partially eroded. In western Cuba, shallow-bank carbonates, similar to those of the [[Vinas Group|Vinas* Group]], accumulated atop the La Rana [https://wwwf.imperial.ac.uk/earthscienceandengineering/rocklibrary/viewglossrecord.php?gID=00000000073 granodiorite] [http://en.wikipedia.org/wiki/Horst_%28geology%29 horst] and formed the Guajaibon–Sierra Azul belt. South of the La Rana basement horst, deep-water limestones of the Mayari, Collantes, and Cobrito Formations were deposited and preserved. |
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| Farther south, rifting continued, accompanied by outpouring of tholeites and other [[Wikipedia:Basic_rock|basic]] to [https://wwwf.imperial.ac.uk/earthscienceandengineering/rocklibrary/viewglossrecord.php?gID=00000000012 ultrabasic] material forming a layered [[Oceanic crust|oceanic basement]] consisting of [http://geology.about.com/od/rocks/ig/igrockindex/rocpicperidotite.htm peridotite], [http://www.britannica.com/EBchecked/topic/223075/gabbro gabbro], sheeted [http://www.britannica.com/EBchecked/topic/163476/dike dikes], [[Wikipedia:Pillow lava|pillow basalts]] (old volcanics of the Domingo* sequence), and associated sediments. Although some genetic relationship exists between the [[Domingo*]] sequence and the El Sabalo–Nueva Maria lithologies, these belong to two entirely different provinces. [[El Sabalo Formation|El Sabalo]] and the [[Nueva Maria Formation]]s, like the granodiorites, belong to the autochthonous nappes and were at the continental margin, whereas the Domingo* sequence forms the base of the allochthonous nappe and is entirely oceanic. | | Farther south, rifting continued, accompanied by outpouring of tholeites and other [[Wikipedia:Basic_rock|basic]] to [https://wwwf.imperial.ac.uk/earthscienceandengineering/rocklibrary/viewglossrecord.php?gID=00000000012 ultrabasic] material forming a layered [[Oceanic crust|oceanic basement]] consisting of [http://geology.about.com/od/rocks/ig/igrockindex/rocpicperidotite.htm peridotite], [http://www.britannica.com/EBchecked/topic/223075/gabbro gabbro], sheeted [http://www.britannica.com/EBchecked/topic/163476/dike dikes], [[Wikipedia:Pillow lava|pillow basalts]] (old volcanics of the Domingo* sequence), and associated sediments. Although some genetic relationship exists between the [[Domingo*]] sequence and the El Sabalo–Nueva Maria lithologies, these belong to two entirely different provinces. [[El Sabalo Formation|El Sabalo]] and the [[Nueva Maria Formation]]s, like the granodiorites, belong to the autochthonous nappes and were at the continental margin, whereas the Domingo* sequence forms the base of the allochthonous nappe and is entirely oceanic. |