Journal of Petroleum Geology, Vol.5,
No.2, pp. 149-160, 1982
©Copyright 2000 Scientific Press,
Ltd.
THE PANGAEAN PARADOX:
WHERE IS IT?
A. R. Crawford*
*Professor of Geology, University
of Canterbury, Christchurch 1, New Zealand.
Abstract
The postulation of a Precambrian (about
1,300 Ma) expansion of the Earth by Embleton et al.
(1981) and Schmidt and Embleton (1981) to explain paradoxical
results from palaeomagnetism, by creating a Pangaea
asymmetrically disposed on the Earth, produces more problems than
it solves. It is preferable to infer that the present pattern of
continent and ocean, which appears to be normal (and is probably
non-random) derives from a Pangaea which covered the Earth
completely or almost completely in the Precambrian and dispersed
during the Mesozoic-Cenozoic at a critical stage of persistent,
exponentially-increasing and perhaps mildly-pulsatory expansion.
In this orderly dispersal, the geometrical relations between the
continents were maintained. Data from palaeomagnetism for the
period 1,000-200 Ma, although amenable to a consistent orthodox
interpretation, may nevertheless be illusory and indicative not
of any different continental pattern (in terms of geocentric
angles) but of some inner disturbance perhaps related to (or at
least concurrent with) large-scale obliquity changes. An earlier
critical stage, represented by the 'Pan African event' over the
period 750-450 Ma, was the time of the first development of
future continental outlines.
