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author Kitchell, Jennifer A
Clark, David L
author_facet Kitchell, Jennifer A
Clark, David L
collection Datos científicos de ciencias marinas y ambientales
contents Quantitative determination of biogenic silica in Late Cretaceous and Paleogene deep-sea sediment cores from the central Arctic Ocean provides evidence of open-ocean polar upwelling. The timing of polar upwelling coincides with periods of a weakened meridional thermal gradient, suggesting that heat transport to the poles by oceanic circulation may have been important. The timing of biogenic silica deposition in the Arctic precedes its deposition in both the Norwegian-Greenland Sea of the North Atlantic and the Bering Sea of the North Pacific. Tectonic events may be responsible for the timing and siting of sites of deposition of biogenic silica in high northern latitudes, particularly the tectonic evolution of sites of deep-water exchange between the Arctic and the world ocean. We outline three phases in the post-mid-Cretaceous history of silica deposition in high northern latitudes. During Phase I, the Arctic is a silica sink, with deep-water formation but with no deep-water outflow. The transition to Phase II is brought about by opening of the Svalbard-Greenland Strait to deep-water outflow from the Arctic to the Norwegian-Greenland Sea. The transition to Phase III is initiated by submergence of the Faroe-Iceland Ridge and deep-water outflow from the Arctic to the North Atlantic. Climatic conditions in the Arctic during Late Cretaceous and Paleogene time are predicted to have favored open-ocean upwelling due to a circulation pattern dominated by cyclonic conditions, resulting from the establishment of a semi-permanent atmospheric low over the Alpha Ridge. Bathymetry of the Alpha Ridge may have intensified paleo-upwelling.
format Dataset Open Access
id pangaea_https___doi_org_10_1594_PANGAEA_701639
institution PANGAEA
language en
publishDate 1982
publisher PANGAEA
record_format pangaea
spellingShingle Mean element and biogenic silica concentrations in Arctic Ocean sediments (Table 1)
Kitchell, Jennifer A
Clark, David L
54-422; 56-437; Aluminium; Atomic absorption spectrometry (AAS); Calculated; Deep Sea Drilling Project; Depth, bottom/max; DEPTH, sediment/rock; Depth, top/min; DRILL; Drilling/drill rig; DSDP; Elevation of event; Event label; Glomar Challenger; Latitude of event; Leg54; Leg56; Longitude of event; Magnesium; North Pacific/RIDGE; North Pacific Ocean; Opal, biogenic silica; Silicon; Silicon dioxide
Quantitative determination of biogenic silica in Late Cretaceous and Paleogene deep-sea sediment cores from the central Arctic Ocean provides evidence of open-ocean polar upwelling. The timing of polar upwelling coincides with periods of a weakened meridional thermal gradient, suggesting that heat transport to the poles by oceanic circulation may have been important. The timing of biogenic silica deposition in the Arctic precedes its deposition in both the Norwegian-Greenland Sea of the North Atlantic and the Bering Sea of the North Pacific. Tectonic events may be responsible for the timing and siting of sites of deposition of biogenic silica in high northern latitudes, particularly the tectonic evolution of sites of deep-water exchange between the Arctic and the world ocean. We outline three phases in the post-mid-Cretaceous history of silica deposition in high northern latitudes. During Phase I, the Arctic is a silica sink, with deep-water formation but with no deep-water outflow. The transition to Phase II is brought about by opening of the Svalbard-Greenland Strait to deep-water outflow from the Arctic to the Norwegian-Greenland Sea. The transition to Phase III is initiated by submergence of the Faroe-Iceland Ridge and deep-water outflow from the Arctic to the North Atlantic. Climatic conditions in the Arctic during Late Cretaceous and Paleogene time are predicted to have favored open-ocean upwelling due to a circulation pattern dominated by cyclonic conditions, resulting from the establishment of a semi-permanent atmospheric low over the Alpha Ridge. Bathymetry of the Alpha Ridge may have intensified paleo-upwelling.
title Mean element and biogenic silica concentrations in Arctic Ocean sediments (Table 1)
topic 54-422; 56-437; Aluminium; Atomic absorption spectrometry (AAS); Calculated; Deep Sea Drilling Project; Depth, bottom/max; DEPTH, sediment/rock; Depth, top/min; DRILL; Drilling/drill rig; DSDP; Elevation of event; Event label; Glomar Challenger; Latitude of event; Leg54; Leg56; Longitude of event; Magnesium; North Pacific/RIDGE; North Pacific Ocean; Opal, biogenic silica; Silicon; Silicon dioxide
url https://doi.org/10.1594/PANGAEA.701639