Journal of Petroleum Geology, Vol.9,
No.2, pp. 207-216, 1986
©Copyright 2000 Scientific Press,
Ltd.
THE EVOLUTION OF OCEAN
BASINS DURING CENOZOIC TIME
V. V. Orlenok*
* USSR Academy of Sciences,
Kaliningrad State University, Kaliningrad, USSR.
Abstract
Evidence has accumulated steadily during
recent years to show that ocean basins are quite young, certainly
younger than Paleozoic and PreCambrian. The most common mechanism
invoked to explain the relatively youthful age of ocean basins is
through sea-floor spreading, i.e. by the theory of
plate-tectonics; however, the Author believes that it can be
explained more logically by a process of
"oceanization", for which clear evidence was shown in
149 of the first 493 DSDP+ boreholes. The oceans began to form
during the Middle Jurassic (the oldest marine strata penetrated
in the boreholes), about 170 MM years++ ago. Beginning in the
Paleogene, the oceans began to deepen more rapidly. This
deepening was accompanied by the effusion of great thicknesses of
plateau basalt. The sinking process was made possible by the
thickening of the asthenosphere beneath the ocean basins, a
process which is continuing towards the continents as these
become "oceanized". It is to be expected that the
entire process will be completed within the next 30 to 50 MM
years.