_version_ 1867170960750149632
author Thompson, Geoffrey
Humphris, Susan E
Schilling, Jean-Guy
author_facet Thompson, Geoffrey
Humphris, Susan E
Schilling, Jean-Guy
collection Datos científicos de ciencias marinas y ambientales
contents Basalts from Hole 516F, DSDP Leg 72 on the Rio Grande Rise are tholeiitic in character but differ from normal mid-ocean ridge basalts in the South Atlantic in higher concentrations of incompatible elements such as Ti, K, V, Sr, Ba, Zr, Nb, and light rare-earth elements and in lower concentrations of Mg, Cr, and Ni. They contrast with previously reported basalts from the Rio Grande Rise, which were highly alkalic in character. The Rio Grande Rise basalts from Hole 516F (age 84.5 Ma) are generally similar to basalts from the eastern end of the Walvis Ridge (80-100 Ma). It is suggested that they either originated, like the Walvis Ridge, from a mantle hot spot that is different from the present-day hot spot (Tristan da Cunha) and that has changed composition with time, or from a spreading center that was shallow and chemically influenced by the adjacent hot spot, similar to the present-day Mid-Atlantic Ridge near the Azores and Tristan da Cunha.
format Dataset Open Access
id pangaea_https___doi_org_10_1594_PANGAEA_811425
institution PANGAEA
language en
publishDate 1983
publisher PANGAEA
record_format pangaea
spellingShingle (Table 1) Basalt geochemsitry at DSDP Hole 72-516F
Thompson, Geoffrey
Humphris, Susan E
Schilling, Jean-Guy
72-516F; Aluminium oxide; Barium; Calcium oxide; Carbon dioxide; Cerium; Chromium; Cobalt; Copper; Deep Sea Drilling Project; DRILL; Drilling/drill rig; DSDP; DSDP/ODP/IODP sample designation; Dysprosium; Element analysis, neutron activation (NAA); Europium; Gadolinium; Glomar Challenger; Iron oxide, Fe2O3; Iron oxide, FeO; Lanthanum; Leg72; Lutetium; Magnesium oxide; Manganese oxide; Neodymium; Nickel; Niobium; Phosphorus pentoxide; Potassium oxide; Rubidium; Samarium; Sample code/label; Scandium; Silicon dioxide; Sodium oxide; South Atlantic/CONT RISE; Strontium; Terbium; Thulium; Titanium dioxide; Total; Vanadium; Water in rock; X-ray fluorescence (XRF); Ytterbium; Yttrium; Zinc; Zirconium
Basalts from Hole 516F, DSDP Leg 72 on the Rio Grande Rise are tholeiitic in character but differ from normal mid-ocean ridge basalts in the South Atlantic in higher concentrations of incompatible elements such as Ti, K, V, Sr, Ba, Zr, Nb, and light rare-earth elements and in lower concentrations of Mg, Cr, and Ni. They contrast with previously reported basalts from the Rio Grande Rise, which were highly alkalic in character. The Rio Grande Rise basalts from Hole 516F (age 84.5 Ma) are generally similar to basalts from the eastern end of the Walvis Ridge (80-100 Ma). It is suggested that they either originated, like the Walvis Ridge, from a mantle hot spot that is different from the present-day hot spot (Tristan da Cunha) and that has changed composition with time, or from a spreading center that was shallow and chemically influenced by the adjacent hot spot, similar to the present-day Mid-Atlantic Ridge near the Azores and Tristan da Cunha.
title (Table 1) Basalt geochemsitry at DSDP Hole 72-516F
topic 72-516F; Aluminium oxide; Barium; Calcium oxide; Carbon dioxide; Cerium; Chromium; Cobalt; Copper; Deep Sea Drilling Project; DRILL; Drilling/drill rig; DSDP; DSDP/ODP/IODP sample designation; Dysprosium; Element analysis, neutron activation (NAA); Europium; Gadolinium; Glomar Challenger; Iron oxide, Fe2O3; Iron oxide, FeO; Lanthanum; Leg72; Lutetium; Magnesium oxide; Manganese oxide; Neodymium; Nickel; Niobium; Phosphorus pentoxide; Potassium oxide; Rubidium; Samarium; Sample code/label; Scandium; Silicon dioxide; Sodium oxide; South Atlantic/CONT RISE; Strontium; Terbium; Thulium; Titanium dioxide; Total; Vanadium; Water in rock; X-ray fluorescence (XRF); Ytterbium; Yttrium; Zinc; Zirconium
url https://doi.org/10.1594/PANGAEA.811425