4. Volcanogenic Sediments in the Indian Ocean
- J.R. Heirtzler,
- H.M. Bolli,
- T.A. Davies,
- J.B. Saunders and
- J.G. Sclater
Published Online: 23 MAR 2013
Copyright © 1977 by the American Geophysical Union.
Indian Ocean Geology and Biostratigraphy
How to Cite
Vallier, T. L. and Kidd, R. B. (1977) Volcanogenic Sediments in the Indian Ocean, in Indian Ocean Geology and Biostratigraphy (eds J.R. Heirtzler, H.M. Bolli, T.A. Davies, J.B. Saunders and J.G. Sclater), American Geophysical Union, Washington, D. C.. doi: 10.1029/SP009p0087
- Published Online: 23 MAR 2013
- Published Print: 1 JAN 1977
Print ISBN: 9780875902081
Online ISBN: 9781118664919
Volcanogenic contributions to sediments in the Indian Ocean are significant not only volumetrically but also as indicators of tectonic events. Major accumulations are related to ocean basin tectonic events such as initial stages of rifting, high spreading rates, the formation of presently aseismic ridges, and to landmass volcanism, some of which is associated with subduction. The composition of volcanism changed with time from basaltic during late Mesozoic and early Cenozoic tensional activity to silicic during the Late Cenozoic as subduction occurred beneath the Indonesian Arc. There was a causal relationship between early stages of sea floor spreading and quantities of volcanogenic sediments; thick basal piles of volcanogenic sediments accumulated during early parts of ocean basin evolution. Volcanogenic sediments on presently aseismic ridges occur both in thick basal piles and in beds higher within the sediment columns. On aseismic ridges, basal sediments probably are related to the initial formation which occurred at the intersection of a mid-ocean ridge and a transform fault, and beds higher in the sediment columns may be related to uplift which formed the present ridge topography.