The Fate of Reef-Derived Sediment on the North Jamaican Island Slope
Land LS. 1979. The Fate of Reef-Derived Sediment on the North Jamaican Island Slope. Marine Geology. 29:55-71
The island slope north of Discovery Bay, Jamaica, consists of a steep, 5 km high, normal faulted monocline of Miocene chalk, dissected by submarine canyons, and partially mantled by palagic brown clay-calcareous ooze. Beds of Holocene sane-sized reef debris are absent on the Island slope and in the adjacent abyssal basins of the Cayman trench. A few thin beds of sand-sized reef-crest sand are locally present less than one meter below the sediment-water interface on the upper Island slope, and resulted from seaward transport during a period of glacially lowered sea level. Minor amounts of sand, silt, and clay-sized reef debris are admixed with pelagic components in the late Pleistocene and Holocene sediments from the upper Island slope and abyssal basins adjacent to the Island slope. Reflection seismic profiles between Jamaica and Cuba suggest the Cayman trench to be a zone of the north-south extension as a result of late Miocene normal faulting which created several kilometers of vertical relief. Eocene sediments may outcrop on horsts in the trench which bound the kilometer thick abyssal basins. Mass balance considerations suggest that half of modern carbonate reef productivity dissolves in adjacent deep water
- Type
- Journal Article
- Authors
- Land, Lynton
- Units
- SFCN
- Keywords
- Fault, Holocene, monocline, Pleistocene, Reef Debris, submarine canyons