Geochemistry and minerals at DSDP LEg 58 Holes, 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
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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ftdatacite:10.1594/pangaea.821390 2023-05-15T16:53:13+02:00 Geochemistry and minerals at DSDP LEg 58 Holes, 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 Marsh, Nicholas G Saunders, Andrew D Tarney, John Dick, Henry J B 1980 application/zip https://dx.doi.org/10.1594/pangaea.821390 https://doi.pangaea.de/10.1594/PANGAEA.821390 en eng PANGAEA - Data Publisher for Earth & Environmental Science https://dx.doi.org/10.2973/dsdp.proc.58.133.1980 Creative Commons Attribution 3.0 Unported https://creativecommons.org/licenses/by/3.0/legalcode cc-by-3.0 CC-BY Drilling/drill rig Leg58 Glomar Challenger Deep Sea Drilling Project DSDP Collection article Supplementary Collection of Datasets 1980 ftdatacite https://doi.org/10.1594/pangaea.821390 https://doi.org/10.2973/dsdp.proc.58.133.1980 2021-11-05T12:55:41Z 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 different basalt types were derived from chemically distinct mantle sources. From comparison of the Leg 58 data with those already available for other intra-oceanic back-arc basins, it appears that the mantle sources giving rise to back-arc-basin basalts are chemically as diverse as those for mid-ocean ridges. In addition, the high vesicularity of the Shikoku Basin basalts supports previous observations that the mantle source of back-arc-basin basalts may be contaminated by a hydrous component from the adjacent subduction zone. Article in Journal/Newspaper Iceland DataCite Metadata Store (German National Library of Science and Technology) Mid-Atlantic Ridge Pacific Saunders ENVELOPE(-45.316,-45.316,-60.700,-60.700) |
institution |
Open Polar |
collection |
DataCite Metadata Store (German National Library of Science and Technology) |
op_collection_id |
ftdatacite |
language |
English |
topic |
Drilling/drill rig Leg58 Glomar Challenger Deep Sea Drilling Project DSDP |
spellingShingle |
Drilling/drill rig Leg58 Glomar Challenger Deep Sea Drilling Project DSDP Marsh, Nicholas G Saunders, Andrew D Tarney, John Dick, Henry J B Geochemistry and minerals at DSDP LEg 58 Holes, 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 |
topic_facet |
Drilling/drill rig Leg58 Glomar Challenger Deep Sea Drilling Project DSDP |
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 different basalt types were derived from chemically distinct mantle sources. From comparison of the Leg 58 data with those already available for other intra-oceanic back-arc basins, it appears that the mantle sources giving rise to back-arc-basin basalts are chemically as diverse as those for mid-ocean ridges. In addition, the high vesicularity of the Shikoku Basin basalts supports previous observations that the mantle source of back-arc-basin basalts may be contaminated by a hydrous component from the adjacent subduction zone. |
format |
Article in Journal/Newspaper |
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, 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 |
title_short |
Geochemistry and minerals at DSDP LEg 58 Holes, 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 |
title_full |
Geochemistry and minerals at DSDP LEg 58 Holes, 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 |
title_fullStr |
Geochemistry and minerals at DSDP LEg 58 Holes, 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 |
title_full_unstemmed |
Geochemistry and minerals at DSDP LEg 58 Holes, 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 |
title_sort |
geochemistry and minerals at dsdp leg 58 holes, 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 |
publisher |
PANGAEA - Data Publisher for Earth & Environmental Science |
publishDate |
1980 |
url |
https://dx.doi.org/10.1594/pangaea.821390 https://doi.pangaea.de/10.1594/PANGAEA.821390 |
long_lat |
ENVELOPE(-45.316,-45.316,-60.700,-60.700) |
geographic |
Mid-Atlantic Ridge Pacific Saunders |
geographic_facet |
Mid-Atlantic Ridge Pacific Saunders |
genre |
Iceland |
genre_facet |
Iceland |
op_relation |
https://dx.doi.org/10.2973/dsdp.proc.58.133.1980 |
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.821390 https://doi.org/10.2973/dsdp.proc.58.133.1980 |
_version_ |
1766043727143370752 |