The Scientific Case for EXPANSION TECTONICS

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The following discourse on the development of the modern oceans and seas, as well as the modern continents and ancient supercontinents, is an extract from part one of my new book: “On the Origin of Continents and Oceans”. Part two of this book takes this small Earth modelling study further by progressively introducing an extensive array of modern geological, geophysical, geographical, and biogeographical evidence to the small Earth models. In all cases it is shown that this evidence substantiates and is far better suited to an Expansion Tectonic Earth model.   

On an Expansion Tectonic Earth, prior to about 250 million years ago there were no modern oceans, only ancient continental seas. Continental seas are bodies of seawater covering low-lying parts of the ancient supercontinental lands. The transition from ancient seas to modern oceans only came about when the ancient Pangaea supercontinent first started to rupture and breakup to form the modern continents and intervening modern oceans.

This breakup then initiated draining the waters of the ancient continental seas into the newly opening modern oceans as well as expulsion of new water and atmospheric gases along the newly established mid-ocean-ridge spreading zones.

On an Expansion Tectonic Earth conventional Panthalassa, Tethys, and Iapetus Oceans cannot be reconciled in their entirety.  Instead, these same ancient oceans initially formed a network of much smaller continental seas covering low-lying areas of the ancient Pangaea supercontinental lands. These seas are represented by a primitive Panthalassa Sea, located between Australia, Asia, and North America; a Tethys Sea, located within the present Eurasian continent; and an Iapetus Sea, located between the ancient West African and North American continental crusts, possibly extending into South America.

The modern oceans initially opened within ruptured areas of continental crust where the Pangaean supercontinental crust had failed to keep pace with changes to the Earth surface area and surface curvature. These rupture zones then progressively opened and rapidly extended in surface area throughout the later Mesozoic and Cenozoic Eras.

On each small Earth model, opening of the modern oceans during the late-Permian and early-Triassic Periods was initially centred in the North Pacific, South Pacific, Arctic, and North Atlantic Ocean regions. Opening of the South Atlantic and Indian Oceans then commenced during mid- to late-Jurassic times, and the Southern Ocean commenced opening during the Paleocene–some 66 million years ago.

Shoreline geography shown on Archaean to present-day small Earth models. The ancient shorelines are shown as blue lines and the ancient seas and modern oceans are shaded blue. Each image advances 15 degrees longitude throughout the sequence to show a broad coverage of geographical development. Note: there was no published data available for the late-Devonian model.

Opening of the modern oceans was accompanied by marked variations in sea-levels. These sea-level changes were in turn accompanied by climate changes and extinction events occurring during crustal breakup, disruptions to the previously established climate zones, polar ice-caps, species habitats, and migration routes.