Record Details
Surface sediments of the Panama Basin : coarse components
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Surface sediments of the Panama Basin : coarse components |
| Names |
Kowsmann, Renato O.
(creator) Heath, G. Ross (advisor) |
| Date Issued | 1972-10-27 (iso8601) |
| Note | Graduation date: 1973 |
| Abstract | The abundance and distribution of biogenic, terrigenous and volcanic particles in the Panama Basin are markedly dependent on bottom topography and dissolution of calcite in the deeper parts of the basin. Of the coarse fraction (>62μ), foraminiferal tests and acidic volcanic glass shards are concentrated on the Cocos and Carnegie Ridges as lag deposits. Foraminiferal fragments are found on these ridge flanks and on the Malpelo Ridge due to reworking by bottom currents accentuated by dissolution of calcite with increasing depth. The finest calcite, probably coccoliths with fine foraminiferal fragments, together with the hydrodynamically light radiolarian skeletons are concentrated by bottom currents in the basin adjacent to the ridges. The foraminiferal calcite compensation depth in the basin is 3400 m. This relatively shallow depth probably reflects the high surface water productivity over the basin, although the pattern of productivity is not reflected in the pattern of biogenic sediments. Acidic volcanic glass appears to have been carried into the basin from Costa Rica, Colombia and Ecuador by easterly winds at altitudes of 1500 to 6000 m. Basaltic shards from the Galapagos Islands have been dispersed only over short distances to the west. Terrigenous sand-sized material is found on the edge of the continental shelf, where associated glauconite points to a relict origin, and along the northern Cocos Ridge, where contour currents may act as the dispersal mechanism. |
| Genre | Thesis/Dissertation |
| Topic | Marine sediments -- Panama Basin |
| Identifier | http://hdl.handle.net/1957/28380 |
