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Over most of its length, the northern coast of Cuba is the dividing line between stable conditions (at least since the Middle [[Jurassic]]) to the north and west and very complex ones to the south. Although it is geologically deformed ([[:file:St58OverviewFG4.JPG|Figure 2]]), the part of the northern coast of Cuba extending from eastern [[Natanzas]] to western Oriente belongs to the Florida-Bahamas carbonate bank province. To the south, in part under an upper Eocene or younger cover, is a relatively narrow belt, 45-160 km (28-99 mi) wide, of intensely folded and faulted Middle Jurassic to middle Eocene rocks consisting, from north to south, of:

Over most of its length, the northern coast of Cuba is the dividing line between stable conditions (at least since the Middle [[Jurassic]]) to the north and west and very complex ones to the south. Although it is geologically deformed ([[:file:St58OverviewFG4.JPG|Figure 2]]), the part of the northern coast of Cuba extending from eastern [[Natanzas]] to western Oriente belongs to the Florida-Bahamas carbonate bank province. To the south, in part under an upper Eocene or younger cover, is a relatively narrow belt, 45-160 km (28-99 mi) wide, of intensely folded and faulted Middle Jurassic to middle Eocene rocks consisting, from north to south, of:

* the north-central sedimentary [[terrane]]s, characterized by very thick [[platform]] [[carbonate]]s and [[evaporite]]s on the north and a relatively thin section of platform to [http://www.merriam-webster.com/dictionary/pelagic pelagic] carbonates and [[chert]]s on the south;

* the north-central sedimentary [[terrane]]s, characterized by very thick [[platform]] [[carbonate]]s and [[evaporite]]s on the north and a relatively thin section of platform to [http://www.merriam-webster.com/dictionary/pelagic pelagic] carbonates and [[chert]]s on the south;

* the [[Ophiolite|ophiolitic]] [[Wikipedia:Basic_rock|basic]] igneous-volcanic (called igneous-volcanic because of being a mixture of [http://www.geolsoc.org.uk/ks3/gsl/education/resources/rockcycle/page3598.html intrusive] and [[Wikipedia:Volcanic_rock|volcanic]] (extrusive) rocks with a general predominance of volcanic rocks) terranes, with [https://wwwf.imperial.ac.uk/earthscienceandengineering/rocklibrary/viewglossrecord.php?gID=00000000012 ultrabasic] intrusive rocks, many types and great thicknesses of basic, [http://geology.com/rocks/basalt.shtml basaltic] to [[Andesite|andesitic]] volcanic rocks, volcanic-derived sediments, and [https://wwwf.imperial.ac.uk/earthscienceandengineering/rocklibrary/viewglossrecord.php?gID=00000000073 granodioritic] intrusives, and

* the [http://geology.about.com/od/platetectonics/a/ophiolite.htm ophiolitic] [[Wikipedia:Basic_rock|basic]] igneous-volcanic (called igneous-volcanic because of being a mixture of [http://www.geolsoc.org.uk/ks3/gsl/education/resources/rockcycle/page3598.html intrusive] and [[Wikipedia:Volcanic_rock|volcanic]] (extrusive) rocks with a general predominance of volcanic rocks) terranes, with [https://wwwf.imperial.ac.uk/earthscienceandengineering/rocklibrary/viewglossrecord.php?gID=00000000012 ultrabasic] intrusive rocks, many types and great thicknesses of basic, [http://geology.com/rocks/basalt.shtml basaltic] to [[Andesite|andesitic]] volcanic rocks, volcanic-derived sediments, and [https://wwwf.imperial.ac.uk/earthscienceandengineering/rocklibrary/viewglossrecord.php?gID=00000000073 granodioritic] intrusives, and

* the southwestern sedimentary terranes, with primarily thin stratigraphic sections of platform to [[pelagic]] [[carbonate]]s and [[chert]]s but locally with great thicknesses of older, continental-derived [[sandstone]]s and [[shale]]s showing various degrees of [[metamorphism]].

* the southwestern sedimentary terranes, with primarily thin stratigraphic sections of platform to [[pelagic]] [[carbonate]]s and [[chert]]s but locally with great thicknesses of older, continental-derived [[sandstone]]s and [[shale]]s showing various degrees of [[metamorphism]].

The most striking feature about the geology of the island is the great disparity between the ophiolite-volcanichttp://www.geolsoc.org.uk/ks3/gsl/education/resources/rockcycle/page3598.html sequence of the basic igneous-volcanic terranes and the sedimentary sequences of the north-central and southwestern sedimentary terranes. Except for a few notable cases, essentially no relationship exists between these sedimentary and igneous terranes. There has been much argument about how the terranes came into contact and became structurally mixed, but it is generally accepted today that the ophiolite-volcanic sequence is totally [[Allochthon|allochthonous]]. [[:file:St58OverviewFG5.JPG|Figure 3]] shows a map of Cuba's major structural features and terrane distribution, and [[:file:St58OverviewFG6.JPG|Figure 4]] shows, in cross section, the structural relations between the various terranes.

The most striking feature about the geology of the island is the great disparity between the [http://geology.about.com/od/platetectonics/a/ophiolite.htm ophiolite]-volcanic [http://www.geolsoc.org.uk/ks3/gsl/education/resources/rockcycle/page3598.html] sequence of the basic igneous-volcanic terranes and the sedimentary sequences of the north-central and southwestern sedimentary terranes. Except for a few notable cases, essentially no relationship exists between these sedimentary and igneous terranes. There has been much argument about how the terranes came into contact and became structurally mixed, but it is generally accepted today that the ophiolite-volcanic sequence is totally [[Allochthon|allochthonous]]. [[:file:St58OverviewFG5.JPG|Figure 3]] shows a map of Cuba's major structural features and terrane distribution, and [[:file:St58OverviewFG6.JPG|Figure 4]] shows, in cross section, the structural relations between the various terranes.

Although Cuba is now part of the North American continent, it is a remnant of a [[Cretaceous]] to early [[Tertiary]] [[orogenic belt]] that has been preserved because of the local configurations of the North American and Caribbean [[plate]]s. As a consequence, Cuba exposes sequences of Upper Jurassic and Cretaceous nonvolcanic pelagic sediments that are rare, if not unique, in the Caribbean as well as in North, Central, and South America. However, Cuba has facies and faunal similarities with equivalent strata of the [[Tethys]] region, specifically the [[Alps]] and Italian [[Apennines]].

Although Cuba is now part of the North American continent, it is a remnant of a [[Cretaceous]] to early [[Tertiary]] [[orogenic belt]] that has been preserved because of the local configurations of the North American and Caribbean [[plate]]s. As a consequence, Cuba exposes sequences of Upper Jurassic and Cretaceous nonvolcanic pelagic sediments that are rare, if not unique, in the Caribbean as well as in North, Central, and South America. However, Cuba has facies and faunal similarities with equivalent strata of the [[Tethys]] region, specifically the [[Alps]] and Italian [[Apennines]].