Equatorial Deformation and SubsidencePaper 3 in a series of 5 papers 'From Geomechanics to Geotectonics'

A model was outlined in a previous paper, dealing with surface area changes imposed on the earth’s (brittle) crust by relative movement of the equatorial bulge: stretching in areas coming under the influence of the bulge; compressions in areas moving away from the bulge. Distortions were predicted to be exaggerated at the interface of the two major crustal types, continental and oceanic.

If it is allowed that the equatorial location is transient – either through mobile plates or mobile poles – this model leads to several inescapable predictions.

1. Evidence of crustal distortions and/or subsidence should be identifiable at the present equator and the obvious place to look for major effects would be at continental-oceanic interfaces.
2. Equatorial locations in previous geological eras might be expected to bear the scars of earlier tensile conditions. Where a paleoequator fortuitously lay along a crustal interface would again be the logical place to seek evidence of major disturbances, e.g. geosynclines.
3. The stretched zones of former equatorial locations would have since been subject to post-equatorial compression. Hence, these zones should show evidence of uplift and/or folding.*

These predictions are open to investigation and the tensile, or equatorial bulge state, is treated initially.