Deep sea drilling on the Ninetyeast Ridge; synthesis and a tectonic model

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doi: 10.1029/SP009p0165
Author(s): Luyendyk, B. P.
Author Affiliation(s): Primary:
Univ. Calif., Dep. Geol. Sci., Santa Barbara, Calif., United States
Volume Title: Indian Ocean geology and biostratigraphy; studies following Deep-Sea Drilling legs 22-29
Volume Author(s): Heirtzler, J. R., editor; Bolli, H. M.; Davies, T. A.; Saunders, J. B.; Sclater, J. G.
Source: Indian Ocean geology and biostratigraphy; studies following Deep-Sea Drilling legs 22-29, edited by J. R. Heirtzler, H. M. Bolli, T. A. Davies, J. B. Saunders and J. G. Sclater, p.165-187. Publisher: Am. Geophys. Union, Washington, D.C., United States. ISBN: 978-1-118-66491-9
Note: In English. 53 refs.; illus. incl. tables, sketch maps
Summary: Legs 22 and 26 of the Deep Sea Drilling Project drilled five sites on the Ninetyeast Ridge. Four main observations emerged: 1) The Ridge has an extrusive volcanic basement with a distinctive petrochemistry. 2) The Ridge is older to the north, ranging from Campanian or older at 90°N to Eocene-Oligocene at 310°S. This age gradient is in the same sense as that for the Indian basin to the west, implying that the Ridge belongs, tectonically, to the Indian plate. 3) It was formed in shallow water, sometimes subaerially, and subsided with time in accordance with known age-depth curves. 4) The Ninetyeast Ridge was formed in more southerly latitudes and has since been transported northwards. These observations, combined with other geophysical data, show that the Ridge is primarily a sunken oceanic island and seamount chain. Reconstructions based on a fixed hot spot assumption demonstrate strong support for this point source model. The model predicts that the Ridge is from 90 to 20 m.y. old and was formed primarily from volcanism associated with a source beneath the Amsterdam-St. Paul islands, but contributions from a source beneath Kerguelen are also probable. The Kerguelen source mainly generated the Broken Ridge and Naturaliste Plateau, and the Kerguelen Plateau between >100 and 80 mybp. Abstract Copyright (1977), by the American Geophysical Union.
Year of Publication: 1977
Research Program: DSDP Deep Sea Drilling Project
Key Words: 07 Marine Geology and Oceanography; Algae; Basalts; Biostratigraphy; Broken Ridge; Cenozoic; Cretaceous; Deep Sea Drilling Project; Distribution; Eocene; Foraminifera; Geochemistry; Hot spots; Igneous rocks; Indian Ocean; Invertebrata; Kerguelen Plateau; Leg 22; Leg 26; Lithostratigraphy; Mesozoic; Microfossils; Miospores; Models; Movement; Nannofossils; Naturaliste Plateau; Ninetyeast Ridge; Oceanography; Oligocene; Paleogene; Palynomorphs; Petrology; Plantae; Plate tectonics; Pollen; Protista; Reconstruction; Seamounts; Sediments; Stratigraphy; Tectonophysics; Tertiary; Thallophytes; Volcanic rocks
Coordinates: S350000 N100000 E1000000 E0800000
Record ID: 1978039304
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