Geochemistry and minerals at DSDP LEg 58 Holes
Leg 58 successfully recovered basalt at Sites 442, 443, and 444, in the Shikoku Basin, and at Site 446 in the Daito Basin. Only at Site 442 did penetration reach unequivocal oceanic layer 2; at the other sites, only off-axis sills and flows were sampled. Petrographic observations indicate that back-...
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1980
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ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.821390 2023-05-15T16:53:06+02:00 Geochemistry and minerals at DSDP LEg 58 Holes Marsh, Nicholas G Saunders, Andrew D Tarney, John Dick, Henry J B MEDIAN LATITUDE: 27.555617 * MEDIAN LONGITUDE: 135.464717 * SOUTH-BOUND LATITUDE: 24.700700 * WEST-BOUND LONGITUDE: 132.774800 * NORTH-BOUND LATITUDE: 29.327500 * EAST-BOUND LONGITUDE: 137.683800 * DATE/TIME START: 1977-12-12T00:00:00 * DATE/TIME END: 1978-01-18T00:00:00 1980-10-29 application/zip, 6 datasets https://doi.pangaea.de/10.1594/PANGAEA.821390 https://doi.org/10.1594/PANGAEA.821390 en eng PANGAEA https://doi.pangaea.de/10.1594/PANGAEA.821390 https://doi.org/10.1594/PANGAEA.821390 CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess CC-BY Supplement to: Marsh, Nicholas G; Saunders, Andrew D; Tarney, John; Dick, Henry J B (1980): Geochemistry of basalts from the Shikoku and Daito Basins, Deep Sea Drilling Project Leg 58. In: deVries Klein, G; Kobayashi, K; et al. (eds.), Initial Reports of the Deep Sea Drilling Project (U.S. Govt. Printing Office), 58, 805-842, https://doi.org/10.2973/dsdp.proc.58.133.1980 58-442A 58-442B 58-443 58-444A 58-446 58-446A Deep Sea Drilling Project DRILL Drilling/drill rig DSDP Glomar Challenger Leg58 North Pacific/BASIN North Pacific/Philippine Sea/BASIN Dataset 1980 ftpangaea https://doi.org/10.1594/PANGAEA.821390 https://doi.org/10.2973/dsdp.proc.58.133.1980 2023-01-20T07:33:10Z Leg 58 successfully recovered basalt at Sites 442, 443, and 444, in the Shikoku Basin, and at Site 446 in the Daito Basin. Only at Site 442 did penetration reach unequivocal oceanic layer 2; at the other sites, only off-axis sills and flows were sampled. Petrographic observations indicate that back-arc basalts from the Shikoku Basin, with the exception of the kaersutite-bearing upper sill at Site 444, are mineralogically similar to basalts being erupted at normal mid-ocean ridges. However, the Shikoku Basin basalts are commonly very vesicular, indicating a high volatile content in the magmas. Site 446 in the Daito Basin penetrated a succession of 23 sills which include both kaersutite-bearing and kaersutite-free basalt varieties. A total of 187 samples from the four sites has been analyzed for major and trace elements using X-ray-fluorescence techniques. Chemically, the basalts from Sites 442 and 443 and the lower sill of Site 444 are subalkaline tholeiites and resemble N-type ocean-ridge basalts found along the East Pacific Rise and at 22° N on the Mid-Atlantic Ridge (MAR), although they are not quite as depleted in certain hygromagmatophile (HYG) elements. They do not show any chemical affinities with island-arc tholeiites. The basalts from Site 446 and from the upper sill at Site 444 show alkaline and tholeiitic tendencies, and are enriched in the more-HYG elements; they chemically resemble enriched or E-type basalts and their differentiates found along sections of the MAR (e.g., 45°N) and on ocean islands (e.g., Iceland and the Azores). Most of the intra-site variation may be attributed to crystal settling within individual massive flows and sills, to high-level fractional crystallization in sub-ridge magma chambers, or, where there is evidence of a long period of magmatic quiescence between units, to batch partial melting. However, the basalts from Sites 442 and 443 and from the lower sill at Site 444 cannot easily be related to those from Site 446 and the upper sill at Site 444, and it is possible that the ... Dataset Iceland PANGAEA - Data Publisher for Earth & Environmental Science Pacific Mid-Atlantic Ridge ENVELOPE(132.774800,137.683800,29.327500,24.700700) |
institution |
Open Polar |
collection |
PANGAEA - Data Publisher for Earth & Environmental Science |
op_collection_id |
ftpangaea |
language |
English |
topic |
58-442A 58-442B 58-443 58-444A 58-446 58-446A Deep Sea Drilling Project DRILL Drilling/drill rig DSDP Glomar Challenger Leg58 North Pacific/BASIN North Pacific/Philippine Sea/BASIN |
spellingShingle |
58-442A 58-442B 58-443 58-444A 58-446 58-446A Deep Sea Drilling Project DRILL Drilling/drill rig DSDP Glomar Challenger Leg58 North Pacific/BASIN North Pacific/Philippine Sea/BASIN Marsh, Nicholas G Saunders, Andrew D Tarney, John Dick, Henry J B Geochemistry and minerals at DSDP LEg 58 Holes |
topic_facet |
58-442A 58-442B 58-443 58-444A 58-446 58-446A Deep Sea Drilling Project DRILL Drilling/drill rig DSDP Glomar Challenger Leg58 North Pacific/BASIN North Pacific/Philippine Sea/BASIN |
description |
Leg 58 successfully recovered basalt at Sites 442, 443, and 444, in the Shikoku Basin, and at Site 446 in the Daito Basin. Only at Site 442 did penetration reach unequivocal oceanic layer 2; at the other sites, only off-axis sills and flows were sampled. Petrographic observations indicate that back-arc basalts from the Shikoku Basin, with the exception of the kaersutite-bearing upper sill at Site 444, are mineralogically similar to basalts being erupted at normal mid-ocean ridges. However, the Shikoku Basin basalts are commonly very vesicular, indicating a high volatile content in the magmas. Site 446 in the Daito Basin penetrated a succession of 23 sills which include both kaersutite-bearing and kaersutite-free basalt varieties. A total of 187 samples from the four sites has been analyzed for major and trace elements using X-ray-fluorescence techniques. Chemically, the basalts from Sites 442 and 443 and the lower sill of Site 444 are subalkaline tholeiites and resemble N-type ocean-ridge basalts found along the East Pacific Rise and at 22° N on the Mid-Atlantic Ridge (MAR), although they are not quite as depleted in certain hygromagmatophile (HYG) elements. They do not show any chemical affinities with island-arc tholeiites. The basalts from Site 446 and from the upper sill at Site 444 show alkaline and tholeiitic tendencies, and are enriched in the more-HYG elements; they chemically resemble enriched or E-type basalts and their differentiates found along sections of the MAR (e.g., 45°N) and on ocean islands (e.g., Iceland and the Azores). Most of the intra-site variation may be attributed to crystal settling within individual massive flows and sills, to high-level fractional crystallization in sub-ridge magma chambers, or, where there is evidence of a long period of magmatic quiescence between units, to batch partial melting. However, the basalts from Sites 442 and 443 and from the lower sill at Site 444 cannot easily be related to those from Site 446 and the upper sill at Site 444, and it is possible that the ... |
format |
Dataset |
author |
Marsh, Nicholas G Saunders, Andrew D Tarney, John Dick, Henry J B |
author_facet |
Marsh, Nicholas G Saunders, Andrew D Tarney, John Dick, Henry J B |
author_sort |
Marsh, Nicholas G |
title |
Geochemistry and minerals at DSDP LEg 58 Holes |
title_short |
Geochemistry and minerals at DSDP LEg 58 Holes |
title_full |
Geochemistry and minerals at DSDP LEg 58 Holes |
title_fullStr |
Geochemistry and minerals at DSDP LEg 58 Holes |
title_full_unstemmed |
Geochemistry and minerals at DSDP LEg 58 Holes |
title_sort |
geochemistry and minerals at dsdp leg 58 holes |
publisher |
PANGAEA |
publishDate |
1980 |
url |
https://doi.pangaea.de/10.1594/PANGAEA.821390 https://doi.org/10.1594/PANGAEA.821390 |
op_coverage |
MEDIAN LATITUDE: 27.555617 * MEDIAN LONGITUDE: 135.464717 * SOUTH-BOUND LATITUDE: 24.700700 * WEST-BOUND LONGITUDE: 132.774800 * NORTH-BOUND LATITUDE: 29.327500 * EAST-BOUND LONGITUDE: 137.683800 * DATE/TIME START: 1977-12-12T00:00:00 * DATE/TIME END: 1978-01-18T00:00:00 |
long_lat |
ENVELOPE(132.774800,137.683800,29.327500,24.700700) |
geographic |
Pacific Mid-Atlantic Ridge |
geographic_facet |
Pacific Mid-Atlantic Ridge |
genre |
Iceland |
genre_facet |
Iceland |
op_source |
Supplement to: Marsh, Nicholas G; Saunders, Andrew D; Tarney, John; Dick, Henry J B (1980): Geochemistry of basalts from the Shikoku and Daito Basins, Deep Sea Drilling Project Leg 58. In: deVries Klein, G; Kobayashi, K; et al. (eds.), Initial Reports of the Deep Sea Drilling Project (U.S. Govt. Printing Office), 58, 805-842, https://doi.org/10.2973/dsdp.proc.58.133.1980 |
op_relation |
https://doi.pangaea.de/10.1594/PANGAEA.821390 https://doi.org/10.1594/PANGAEA.821390 |
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.821390 https://doi.org/10.2973/dsdp.proc.58.133.1980 |
_version_ |
1766043612041183232 |