Heavy and light minerals in turbidites from DSDP Hole 19-183, the Aleutian abyssal plain
The Aleutian abyssal plain is a fossil abyssal plain of Paleogene age in the western Gulf of Alaska. The plain is a large, southward-thinning turbidite apron now cut off from sediment sources by the Aleutian Trench. Turbidite sedimentation ceased about 30 m.y. ago, and the apron is now buried under...
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ftdatacite:10.1594/pangaea.721042 2023-05-15T17:04:41+02:00 Heavy and light minerals in turbidites from DSDP Hole 19-183, the Aleutian abyssal plain Stewart, Richard J 1976 application/zip https://dx.doi.org/10.1594/pangaea.721042 https://doi.pangaea.de/10.1594/PANGAEA.721042 en eng PANGAEA - Data Publisher for Earth & Environmental Science https://dx.doi.org/10.1130/0016-7606(1976)87<793:totaap>2.0.co;2 Creative Commons Attribution 3.0 Unported https://creativecommons.org/licenses/by/3.0/legalcode cc-by-3.0 CC-BY Drilling/drill rig Leg19 Glomar Challenger Deep Sea Drilling Project DSDP Collection article Collection of Datasets 1976 ftdatacite https://doi.org/10.1594/pangaea.721042 https://doi.org/10.1130/0016-7606(1976)87<793:totaap>2.0.co;2 2021-11-05T12:55:41Z The Aleutian abyssal plain is a fossil abyssal plain of Paleogene age in the western Gulf of Alaska. The plain is a large, southward-thinning turbidite apron now cut off from sediment sources by the Aleutian Trench. Turbidite sedimentation ceased about 30 m.y. ago, and the apron is now buried under a thick blanket of pelagic deposits. Turbidites of the plain were recovered at site 183 of the Deep Sea Drilling Project on the northern edge of the apron. The heavy-mineral fraction of sand-sized samples is mostly amphibole and epidote with minor pyroxene, garnet, and sphene. The light-mineral fraction is mostly quartzose debris and feldspars. Subordinate lithic fragments consist of roughly equal amounts of metamorphic, plutonic, sedimentary, and volcanic grains. The sand compositions are arkoses in many sandstone classifications, although if fine silt is included with clay as matrix, the sand deposits are feldspathic or lithofeldspathic graywacke. The sands are apparently first-cycle products of deep dissection into a plutonic terrane, and they contrast sharply with arc-derived volcanic sandstones of similar age common on the adjacent North American continental margin. The turbidite sands are stratigraphically remarkably constant in composition, which indicates derivation from virtually the same terrane through a time span approaching 20 m.y. Comparison of Aleutian plain data with the compositions of coeval sedimentary rocks from the northeast Pacific margin shows that the Kodiak shelf area includes possible proximal equivalents of the more distal turbidites. Derivation from the volcaniclastic Mesozoic flysch of the Shumagin-Kodiak shelf is unlikely; more probably the sediments were derived from primary plutonic sources. The turbidites also resemble deposits in the Chugach Mountains and the younger turbidites of the Alaskan abyssal plain and could conceivably have been derived from the coast ranges of southeastern Alaska or western British Columbia. The Aleutian plain sediment most likely was not derived from as far south as the Oregon-Washington continental margin, where coeval sedimentary deposits are dominantly volcaniclastic. Article in Journal/Newspaper Kodiak Alaska DataCite Metadata Store (German National Library of Science and Technology) Gulf of Alaska Pacific |
institution |
Open Polar |
collection |
DataCite Metadata Store (German National Library of Science and Technology) |
op_collection_id |
ftdatacite |
language |
English |
topic |
Drilling/drill rig Leg19 Glomar Challenger Deep Sea Drilling Project DSDP |
spellingShingle |
Drilling/drill rig Leg19 Glomar Challenger Deep Sea Drilling Project DSDP Stewart, Richard J Heavy and light minerals in turbidites from DSDP Hole 19-183, the Aleutian abyssal plain |
topic_facet |
Drilling/drill rig Leg19 Glomar Challenger Deep Sea Drilling Project DSDP |
description |
The Aleutian abyssal plain is a fossil abyssal plain of Paleogene age in the western Gulf of Alaska. The plain is a large, southward-thinning turbidite apron now cut off from sediment sources by the Aleutian Trench. Turbidite sedimentation ceased about 30 m.y. ago, and the apron is now buried under a thick blanket of pelagic deposits. Turbidites of the plain were recovered at site 183 of the Deep Sea Drilling Project on the northern edge of the apron. The heavy-mineral fraction of sand-sized samples is mostly amphibole and epidote with minor pyroxene, garnet, and sphene. The light-mineral fraction is mostly quartzose debris and feldspars. Subordinate lithic fragments consist of roughly equal amounts of metamorphic, plutonic, sedimentary, and volcanic grains. The sand compositions are arkoses in many sandstone classifications, although if fine silt is included with clay as matrix, the sand deposits are feldspathic or lithofeldspathic graywacke. The sands are apparently first-cycle products of deep dissection into a plutonic terrane, and they contrast sharply with arc-derived volcanic sandstones of similar age common on the adjacent North American continental margin. The turbidite sands are stratigraphically remarkably constant in composition, which indicates derivation from virtually the same terrane through a time span approaching 20 m.y. Comparison of Aleutian plain data with the compositions of coeval sedimentary rocks from the northeast Pacific margin shows that the Kodiak shelf area includes possible proximal equivalents of the more distal turbidites. Derivation from the volcaniclastic Mesozoic flysch of the Shumagin-Kodiak shelf is unlikely; more probably the sediments were derived from primary plutonic sources. The turbidites also resemble deposits in the Chugach Mountains and the younger turbidites of the Alaskan abyssal plain and could conceivably have been derived from the coast ranges of southeastern Alaska or western British Columbia. The Aleutian plain sediment most likely was not derived from as far south as the Oregon-Washington continental margin, where coeval sedimentary deposits are dominantly volcaniclastic. |
format |
Article in Journal/Newspaper |
author |
Stewart, Richard J |
author_facet |
Stewart, Richard J |
author_sort |
Stewart, Richard J |
title |
Heavy and light minerals in turbidites from DSDP Hole 19-183, the Aleutian abyssal plain |
title_short |
Heavy and light minerals in turbidites from DSDP Hole 19-183, the Aleutian abyssal plain |
title_full |
Heavy and light minerals in turbidites from DSDP Hole 19-183, the Aleutian abyssal plain |
title_fullStr |
Heavy and light minerals in turbidites from DSDP Hole 19-183, the Aleutian abyssal plain |
title_full_unstemmed |
Heavy and light minerals in turbidites from DSDP Hole 19-183, the Aleutian abyssal plain |
title_sort |
heavy and light minerals in turbidites from dsdp hole 19-183, the aleutian abyssal plain |
publisher |
PANGAEA - Data Publisher for Earth & Environmental Science |
publishDate |
1976 |
url |
https://dx.doi.org/10.1594/pangaea.721042 https://doi.pangaea.de/10.1594/PANGAEA.721042 |
geographic |
Gulf of Alaska Pacific |
geographic_facet |
Gulf of Alaska Pacific |
genre |
Kodiak Alaska |
genre_facet |
Kodiak Alaska |
op_relation |
https://dx.doi.org/10.1130/0016-7606(1976)87<793:totaap>2.0.co;2 |
op_rights |
Creative Commons Attribution 3.0 Unported https://creativecommons.org/licenses/by/3.0/legalcode cc-by-3.0 |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1594/pangaea.721042 https://doi.org/10.1130/0016-7606(1976)87<793:totaap>2.0.co;2 |
_version_ |
1766058994721357824 |