The Scientific Case for EXPANSION TECTONICS

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The conventional plate tectonic supercontinental assemblage of Gondwana  is made up of an assemblage of the present-day South America, Africa, Arabia, Madagascar, India, Australia, and Antarctican continents, as well as crustal fragments from Florida, southern and central Europe, Turkey, Iran, Afghanistan, Tibet, and New Zealand. This conventional assemblage shows that these present continents were assembled into large, separate northern and southern Gondwana supercontinents plus smaller sub-continents separated by a number of largely inferred ancient oceans. The assemblage is said to have formed during a Pan-African tectonic event, occurring at the end of the Precambrian.

The Ordovician Gondwana Expansion Tectonic small Earth assemblage. This model shows the ancient coastline distribution (blue lines) defining North and South Gondwana in relation to Laurentia, Baltica, and Laurussia. The ancient Tethys, Iapetus, and Panthalassa Seas form part of a global network of continental seas (shaded areas) surrounding each of the exposed supercontinents.

From its initial assemblage, the conventional Gondwana assemblage is then said to have remained intact throughout the Palaeozoic to Early Mesozoic times. As a number of researchers have noted though:

...past movements of the Gondwana supercontinent, based on ancient magnetic, biogeographic and climatic evidence, are both equivocal and contentious, and this contention still remains despite the addition of new data from Africa and Australia.

Gondwana on an Expansion Tectonic Earth is shown reconstructed on the Ordovician small Earth model above. The published ancient coastal outlines are also shown as blue lines and the continental seas as shaded blue areas. These coastal outlines, which simply represent the global distribution of the ancient beaches existing at that time, were plotted from published geographical data. This distribution of ancient coastlines, in effect, defines the outlines and locations of the ancient supercontinents and lesser sub-continents as well as the distribution of continental seas existing at that time. The distribution of the ancient coastlines then enables the various ancient continental seas to be located and named.

On Expansion Tectonic small Earth models, prior to the early-Triassic there were no ancient oceans. The need for ancient oceans is an artefact of conventional tectonic studies, whereby largely hypothetical ancient oceans are required in order to maintain a constant surface area Earth. While seeming to be a contradiction of terminology, on an Expansion Tectonic Earth a clear distinction is made between the terms modern oceans and ancient seas. To comply with conventional naming, rather than refer to the oceans as ancient oceans, these are simply called continental seas. This usage is limited to the more familiar ancient Tethys Sea, Panthalassa Sea, and Iapetus Sea.

On the Ordovician Expansion Tectonic small Earth model the Gondwana supercontinental assemblage is the outcome of an evolving change in coastal outlines and sea-levels. These coastal outlines progressively evolved from outlines seen on the earlier Proterozoic Rodinia supercontinent and are a direct result of changing Earth surface curvature during an increase in Earth radius.

During this Gondwanan time the Earth surface underwent a steady to rapid increase in area and was fast approaching crustal rupture—the moment in time when the continental crusts first began to fail and breakup. This Gondwana crustal assemblage retained the exact same configuration of cratons, orogens, and basins as seen in both the Rodinia and primordial Archaean supercontinents. The only difference being the greater surface area of surrounding sedimentary basins and hence aerial distribution of continental seas. This crustal assemblage is retained still further until initiation of crustal rupture and breakup of the pan-global continental crust to form Pangaea occurred during the late-Permian.

The coastal information shown on the Ordovician small Earth model shows that, at that time there were distinct elevated ancient land surfaces. These land surfaces were in turn surrounded by a network of equally distinct, relatively shallow continental seas. Gondwana on this model was subdivided into a North and South Gondwana, separated in part by an early Panthalassa Sea—the precursor to the modern Pacific Ocean. North Gondwana was made up of Australia, East and West Antarctica, and India and also possibly included Tibet and Afghanistan. South Gondwana, joined at Madagascar, comprised Africa, Arabia, and South America. The ancient sub-continents, called Laurentia and Baltica, were made up of North America, Greenland, and Scandinavia, as well as smaller Precambrian fragments now represented by England and Ireland. Similarly, the ancient Laurussia sub-continent was centred on the Precambrian regions of Mongolia and northern Russia.

Each of these exposed Gondwanan land surfaces were in turn surrounded and interconnected by the ancient continental Tethys, Iapetus, and Panthalassa Seas. Remnants of these seas are now preserved and represented by many of the ancient sedimentary basins that are located in Eastern Australia, North and South America, Europe, Asia, and Africa.

This Expansion Tectonic small Earth Gondwana assemblage, however, differs markedly from plate tectonic reconstructions.

On an Expansion Tectonic Earth Eastern Australia, for instance, is assembled adjacent to both North America and South America and is separated by a narrow Panthalassa Sea, as distinct from the need for a very much wider conventional Panthalassa Ocean.

The existing physical and geological similarities between the Australian and South American continents have long been acknowledged in a number of publications. These similarities include the distribution of marine and terrestrial plants and animals, which link Australia with New Zealand across to Central and Southern America, and also rock and fossil types that link Australia directly with South America. It should be appreciated that these physical links between each of these modern continents can only be maintained on an Earth that had a much-reduced ancient radius.

In contrast, because of the plate tectonic requirement for a very large ancient Panthalassa Ocean, conventional reconstructions generate enormous separations which cannot be justified or reconciled with the factual geological or geographical evidence.

The interval of time that Gondwana existed on an Expansion Tectonic Earth is characterised by a rapidly accelerating phase of increasing surface area and accompanying changes in surface curvature. These accelerating changes gave rise to a marked increase in erosion and deposition of sediments and marked changes to the distribution of continental seas and coastal outlines. The increasing changes in surface curvature also initiated localised compression of the sedimentary basins to form long linear fold mountain belts, further disrupting established seaways.

It is significant to note that these times also coincided with the rapid development and evolution of all life forms on Earth. Evolution of species is often seen as driven by the need to keep pace with environmental change and similarly extinction is seen as a by-product of not being able to keep pace with environmental change. The degree of crustal change during this interval of time certainly had the capacity to markedly influence evolutionary change in all life forms.

During Gondwanan times, the Expansion Tectonic Earth South Pole was located within central West Africa in what was then South Gondwana. The North Pole was located within Northern China in what was part of the Tethys Sea. The ancient equator passed through East Antarctica, central Australia, North America, central Eurasia, and India, through what was then North Gondwana. This geographic configuration approximates plate tectonic reconstructions in part, but differs substantially in the South Pacific region because plate tectonics requires the presence of a wide expanse of Panthalassa Ocean.

The distribution of Expansion Tectonic coastal outlines and seas also show that continental land connections existed between north Australia and North America and between north Africa-Arabia and Scandinavia. The existence of these land connections formed important migration routes or barriers for terrestrial and marine life forms. A change in configuration of the various continental seas may have also resulted in periods of relatively rapid sea-level changes in these areas, with disastrous consequences for plant and animal species existing at the time.

The late-Palaeozoic to early-Mesozoic times eventually coincided with the initial breakup of the Gondwana supercontinent, which was accompanied by draining of the continental Tethys, Panthalassa, and Iapetus Seas as the modern oceans began to open. As a result of this draining of the seas each of the Gondwana and related supercontinents geographically merged with the smaller Laurentia, Baltica, and Laurussia sub-continents to form the more familiar Pangaea supercontinent.

On an Expansion Tectonic Earth this evolution of continents and seaways is reflected in the progressive changes to coastal outlines and sea levels, as faithfully displayed in each of the small Earth models.