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Journal of Petroleum Geology, Vol.2,
No.2, pp. 181-197, 1979
©Copyright 2000 Scientific Press,
Ltd.
SHIFTING DEPOSITIONAL AXES OF
IRAQ: AN OUTLINE OF GEOSYNCLINAL HISTORY
M. W. Ibrahim*
*Department of Geology, Imperial
College, London SW7.
Abstract
Isopach-lithofacies maps, presented in this
paper as maps showing depositional axes (depo-axes) for
successive informal lithostratigraphic groups of sedimentary
units, are applied to outline the tectonic history of Iraq. Five
geosynclinal stages are recognised: (a) Intra-Cratonic Basinal
stage, (b) Early Orthogeosynclinal stage, (c) Late
Orthogeosynclinal stage, (d) Idiogeosynclinal stage and (e)
Exogeosynclinal stage. In general, throughout those stages,
depo-axes were always migrating away from the
tectonically-elevated crustal elements during tectonic events and
advancing towards them after the lapse of each tectonic pulse
when normal sedimentation was resumed. The pattern, history and
position of the axes of deposition determined the hydrocarbon
migration directions: these were generally from the ENE towards
the WSW of Iraq.
