Chemical composition of basalts from the Atlantic Ocean
Basalt recovered beneath Jurassic sediments in the western Atlantic at Deep Sea Drilling Project sites 100 and 105 of leg 11 has petrographic features characteristic of water-quenched basalt extruded along modern ocean ridges. Site 100 basalt appears to represent two or three massive cooling units,...
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1977
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ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.667495 2023-05-15T17:30:08+02:00 Chemical composition of basalts from the Atlantic Ocean Bryan, Wilfred B Frey, Frederick A Thompson, Geoffrey MEDIAN LATITUDE: 30.520657 * MEDIAN LONGITUDE: -71.156043 * SOUTH-BOUND LATITUDE: 24.687800 * WEST-BOUND LONGITUDE: -73.799700 * NORTH-BOUND LATITUDE: 34.895300 * EAST-BOUND LONGITUDE: -69.173300 * DATE/TIME START: 1970-04-20T00:00:00 * DATE/TIME END: 1970-05-13T00:00:00 1977-11-09 application/zip, 7 datasets https://doi.pangaea.de/10.1594/PANGAEA.667495 https://doi.org/10.1594/PANGAEA.667495 en eng PANGAEA https://doi.pangaea.de/10.1594/PANGAEA.667495 https://doi.org/10.1594/PANGAEA.667495 CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess CC-BY Supplement to: Bryan, Wilfred B; Frey, Frederick A; Thompson, Geoffrey (1977): Oldest Atlantic seafloor. Contributions to Mineralogy and Petrology, 64(2), 223-242, https://doi.org/10.1007/BF00371513 11-100 11-105 Deep Sea Drilling Project DRILL Drilling/drill rig DSDP Glomar Challenger Leg11 North Atlantic/BASIN North Atlantic/HILL Dataset 1977 ftpangaea https://doi.org/10.1594/PANGAEA.667495 https://doi.org/10.1007/BF00371513 2023-01-20T07:31:05Z Basalt recovered beneath Jurassic sediments in the western Atlantic at Deep Sea Drilling Project sites 100 and 105 of leg 11 has petrographic features characteristic of water-quenched basalt extruded along modern ocean ridges. Site 100 basalt appears to represent two or three massive cooling units, and an extrusive emplacement is probable. Site 105 basalt is less altered and appears to be a compositionally homogeneous pillow lava sequence related to a single eruptive episode. Although the leg 11 basalts are much more closely related in time to the Triassic lavas and intrusives of eastern continental North America, their geochemical features are closely comparable to those of modern Mid-Atlantic Ridge basalts unrelated to postulated "mantle plume" activity. Projection of leg 11 sites back along accepted spreading "flow lines" to their presumed points of origin shows that these origins are also outside the influence of modern" plume" activity. Thus, these oldest Atlantic seafloor basalts provide no information on the time of initiation of these "plumes". The Triassic continental diabases show north to south compositional variations in Rb, Ba, La, and Sr which lie within the range of " plume "-related basalt on the Mid-Atlantic Ridge (20° - 40° N) This suggests that these diabases had mantle sources similar in composition to those beneath the present Mid-Atlantic Ridge. "Plumes" related to deep mantle sources may have contributed to the LIL-element enrichment in the Triassic diabase and may also have been instrumental in initiating the rifting of the North Atlantic. Systematically high values for K and Sr87/Sr86 in the Triassic diabases may reflect superimposed effects of crustal contamination in the Triassic magmas. Dataset North Atlantic PANGAEA - Data Publisher for Earth & Environmental Science Mid-Atlantic Ridge ENVELOPE(-73.799700,-69.173300,34.895300,24.687800) |
institution |
Open Polar |
collection |
PANGAEA - Data Publisher for Earth & Environmental Science |
op_collection_id |
ftpangaea |
language |
English |
topic |
11-100 11-105 Deep Sea Drilling Project DRILL Drilling/drill rig DSDP Glomar Challenger Leg11 North Atlantic/BASIN North Atlantic/HILL |
spellingShingle |
11-100 11-105 Deep Sea Drilling Project DRILL Drilling/drill rig DSDP Glomar Challenger Leg11 North Atlantic/BASIN North Atlantic/HILL Bryan, Wilfred B Frey, Frederick A Thompson, Geoffrey Chemical composition of basalts from the Atlantic Ocean |
topic_facet |
11-100 11-105 Deep Sea Drilling Project DRILL Drilling/drill rig DSDP Glomar Challenger Leg11 North Atlantic/BASIN North Atlantic/HILL |
description |
Basalt recovered beneath Jurassic sediments in the western Atlantic at Deep Sea Drilling Project sites 100 and 105 of leg 11 has petrographic features characteristic of water-quenched basalt extruded along modern ocean ridges. Site 100 basalt appears to represent two or three massive cooling units, and an extrusive emplacement is probable. Site 105 basalt is less altered and appears to be a compositionally homogeneous pillow lava sequence related to a single eruptive episode. Although the leg 11 basalts are much more closely related in time to the Triassic lavas and intrusives of eastern continental North America, their geochemical features are closely comparable to those of modern Mid-Atlantic Ridge basalts unrelated to postulated "mantle plume" activity. Projection of leg 11 sites back along accepted spreading "flow lines" to their presumed points of origin shows that these origins are also outside the influence of modern" plume" activity. Thus, these oldest Atlantic seafloor basalts provide no information on the time of initiation of these "plumes". The Triassic continental diabases show north to south compositional variations in Rb, Ba, La, and Sr which lie within the range of " plume "-related basalt on the Mid-Atlantic Ridge (20° - 40° N) This suggests that these diabases had mantle sources similar in composition to those beneath the present Mid-Atlantic Ridge. "Plumes" related to deep mantle sources may have contributed to the LIL-element enrichment in the Triassic diabase and may also have been instrumental in initiating the rifting of the North Atlantic. Systematically high values for K and Sr87/Sr86 in the Triassic diabases may reflect superimposed effects of crustal contamination in the Triassic magmas. |
format |
Dataset |
author |
Bryan, Wilfred B Frey, Frederick A Thompson, Geoffrey |
author_facet |
Bryan, Wilfred B Frey, Frederick A Thompson, Geoffrey |
author_sort |
Bryan, Wilfred B |
title |
Chemical composition of basalts from the Atlantic Ocean |
title_short |
Chemical composition of basalts from the Atlantic Ocean |
title_full |
Chemical composition of basalts from the Atlantic Ocean |
title_fullStr |
Chemical composition of basalts from the Atlantic Ocean |
title_full_unstemmed |
Chemical composition of basalts from the Atlantic Ocean |
title_sort |
chemical composition of basalts from the atlantic ocean |
publisher |
PANGAEA |
publishDate |
1977 |
url |
https://doi.pangaea.de/10.1594/PANGAEA.667495 https://doi.org/10.1594/PANGAEA.667495 |
op_coverage |
MEDIAN LATITUDE: 30.520657 * MEDIAN LONGITUDE: -71.156043 * SOUTH-BOUND LATITUDE: 24.687800 * WEST-BOUND LONGITUDE: -73.799700 * NORTH-BOUND LATITUDE: 34.895300 * EAST-BOUND LONGITUDE: -69.173300 * DATE/TIME START: 1970-04-20T00:00:00 * DATE/TIME END: 1970-05-13T00:00:00 |
long_lat |
ENVELOPE(-73.799700,-69.173300,34.895300,24.687800) |
geographic |
Mid-Atlantic Ridge |
geographic_facet |
Mid-Atlantic Ridge |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
Supplement to: Bryan, Wilfred B; Frey, Frederick A; Thompson, Geoffrey (1977): Oldest Atlantic seafloor. Contributions to Mineralogy and Petrology, 64(2), 223-242, https://doi.org/10.1007/BF00371513 |
op_relation |
https://doi.pangaea.de/10.1594/PANGAEA.667495 https://doi.org/10.1594/PANGAEA.667495 |
op_rights |
CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1594/PANGAEA.667495 https://doi.org/10.1007/BF00371513 |
_version_ |
1766125939668811776 |