Changes

===Turonian-Campanian===

===Turonian-Campanian===

[[Turonian]] and [[Coniacian]] sediments are not common across most of the nonvolcanic area (80 Ma; [[:file:St58OverviewFG30.JPG|Figure 10]]). They are present to the north in the Cayo Coco area, to the south in the Seibabo area in central Cuba, and in a few units of the southern and northern Rosario belts in western Cuba. The strata above and below the missing interval all have deep-water characteristics, and no evidence of subaerial erosion exists to explain the lack of the Turonian and Coniacian sediments across such a large area. Either there was no deposition, or the section was eroded because of changes in current patterns or submarine slides. Local erosion is unlikely because a hiatus of the same age has been found in many of the holes drilled by the DSDP in the southern Gulf of Mexico and the western Atlantic. Toward the north, in the platform to deep-water province, whatever sediments remain show that sedimentation continued under pelagic conditions and was essentially calcareous, with subordinate [[chert]]s.

[[Turonian]] and [[Coniacian]] sediments are not common across most of the nonvolcanic area (80 Ma; [[:file:St58OverviewFG30.JPG|Figure 10]]). They are present to the north in the Cayo Coco area, to the south in the Seibabo area in central Cuba, and in a few units of the southern and northern Rosario belts in western Cuba. The strata above and below the missing interval all have deep-water characteristics, and no evidence of subaerial erosion exists to explain the lack of the Turonian and Coniacian sediments across such a large area. Either there was no deposition, or the section was eroded because of changes in current patterns or submarine slides. Local erosion is unlikely because a hiatus of the same age has been found in many of the holes drilled by the [http://www.deepseadrilling.org/ Deep Sea Drilling Project (DSDP)] in the southern Gulf of Mexico and the western Atlantic. Toward the north, in the platform to deep-water province, whatever sediments remain show that sedimentation continued under pelagic conditions and was essentially calcareous, with subordinate [[chert]]s.

Toward the south in the basic igneous-volcanic province, conditions were also dominantly pelagic. Sedimentation was accompanied by a renewal of volcanism, with an outpouring of flows and other [[Wikipedia:Ejecta|ejecta]] of a more rhyolitic composition (Pastora* Group). Evidence of subaerial volcanism (such as glass bombs and ash beds) exists. Shallow-water [[reef]]s with [[rudist]]s, [[coral]]s, and large [[foraminifera]] are commonly associated with the volcanics and volcaniclastics. This was the period of major [http://geology.about.com/library/bl/blnutshell_subducfactory.htm arc volcanism] associated with subduction. It was also the time of intrusion of the Manicaragua granodiorite into the central Cuba volcanics.

Toward the south in the basic igneous-volcanic province, conditions were also dominantly pelagic. Sedimentation was accompanied by a renewal of volcanism, with an outpouring of flows and other [[Wikipedia:Ejecta|ejecta]] of a more rhyolitic composition (Pastora* Group). Evidence of subaerial volcanism (such as glass bombs and ash beds) exists. Shallow-water [[reef]]s with [[rudist]]s, [[coral]]s, and large [[foraminifera]] are commonly associated with the volcanics and volcaniclastics. This was the period of major [http://geology.about.com/library/bl/blnutshell_subducfactory.htm arc volcanism] associated with subduction. It was also the time of intrusion of the Manicaragua granodiorite into the central Cuba volcanics.