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biotic species. in a change in exposed continental land, in the distribution of cli- This geological and geophysical information is traditionally mate-dependent sedimentary rocks such as limestone, and in the used in plate tectonic reconstructions of continents to limit plate- distribution of certain marine and terrestrial species which depend fit options imposed by palaeomagnetics on a constant-radius on specific climate zones to survive. Earth. In many instances, the information is contradictory; in par- Reconstructions of the conventional Rodinia, Gondwana and ticular, climate-critical floral and faunal information from bio- Pangaea supercontinents and smaller sub-continents on an geography and distribution of climate-dependent rocks such as expanding Earth demonstrate that, instead of being a random dis- limestone, coal and glacial debris. On an expanding Earth, there — persion-amalgamation or collisional event, each continental is only one plate-fit option. If the geological and geophysical assemblage is progressive and represents an evolutionary process information is not supported or substantiated by the reconstruc- over time. The distinguishing feature of continents constructed on tion, then the reconstruction is wrong; there are no alternative fit- each expanding Earth model is the interrelationship of continental options available. sedimentary basins, the network of continental seas and the net- Published palaeomagnetic information can be plotted on work of crustal movements. The variation of each of these in expanding Earth models to locate the magnetic poles and derive __ time results in a change in exposed continental land. an equator. The information demonstrates the pole data plot as Supercontinent configuration is then defined by the progressive diametrically opposed north and south poles for every era and change in continental sedimentary basins, by crustal movements, period from the Archaean to Recent. Locations of the equators and by the changing sea-level as modern oceans open and rapidly agree in principle with conventional locations based on climate expand to the present. indicators. The clustering of north and south poles is impossible, Instead of mountains forming by continental collision, on an however, on conventional plate tectonic models and demonstrates expanding Earth—they form by vertical uplift, creating plateaus. that palaeomagnetic data can be more effectively used to quantify Changes in surface curvature during Earth expansion cause conti- the location of ancient poles on an nental interiors to remain elevated or expanding Earth. arched relative to the surrounding downwarped sedimentary basins. PALAEOGEOGRAPHY Periodic gravitational collapse of the The ancient geography of our Earth i i interiors of each continent results in forms the basis for defining the inter- Instead of mountains forming uplift and faulting along the conti- relationships of exposed continenta by continental collision, nental margins, forming escarp- areas, intervening seaways, mountains H ments. This process is cyclical dur- and crustal movements, and enables on an expanding Earth they ing ongoing expansion, resulting in the conventional ancient continents of form by vertical uplift, multiple and overlapping phases of Pangaea, Gondwana, Laurentia, . mountain building, erosion, plana- Baltica, Laurussia and Rodinia to be creating plateaus. tion, sedimentation, uplift and fur- quantified on an expanding Earth. ther erosion. On plate tectonic reconstructions of continents, large ancient oceans— PALAEOBIOGEOGRAPHY Panthallassa, Tethys and Iapetus—are Palaeobiogeography is a study of required during times when continents were assembled into super- the distribution of ancient flora and fauna. On an expanding continents. However, outlines of ancient coastal geography plot- Earth, ancient fauna and flora can be used to illustrate their distri- ted on expanding Earth models (figure 1) show that large bution in relation to ancient geography and in relation to estab- Panthallassa, Tethys and Iapetus oceans are not required because lished poles and equators. all modern oceans are removed and continents are assembled as a The distribution of various marine fauna—such as the single continental crust at a reduced Earth radius. Instead, these Cambrian and Ordovician (560 to 440 million years ago) trilobites inferred oceans are replaced by smaller Panthallassa, Tethys and (segmented cockroach-like marine creatures)—on an expanding Iapetus seas, located on or between the ancient continents. Earth demonstrates the ease and simplification of migration and On an expanding Earth, the early Panthall. development of these creatures during the Palaeozoic era, without developed during the Early Permian to Early Jurassic the need for complex conventional continental assemblage-disper- to 160 million years ago) as shallow sedimentary basins within sal requirements. Barriers to migration of trilobites and other the present northwest Pacific Ocean and north Atlantic Ocean marine species on an expanding Earth are then limited to deep- regions respectively. These then progressively opened and marine restrictions and, to a limited extent, latitude and climate extended throughout the Mesozoic and Cenozoic eras as the mod- extremes. ern Pacific and Atlantic oceans. Tria to Cretaceous dinosaurs plotted on expanding Earth In contrast, the Tethys Sea had its origins during the Early models demonstrate that dinosaur distributions are clustered with- Proterozoic era as a continental sea located within Europe and in three distinct provinces, coinciding with the distribution of Asia, progressively enlarging and extending in area during the ancestral Permian reptiles. These include distributions clustered Proterozoic, Palaeozoic and Mesozoic eras. It is now represented —_in Europe and the Mediterranean region, in central and eastern by continental Europe and Asia and the Mediterranean Sea. North America, and in the adjacent South African and southern Changes in sea-level on an expanding Earth occur in response South American regions, with links to India. Isolated distribu- to climatic change, to a shift in the distribution of continental tions also occur in eastern Australia, southern China and western seas, to crustal movements, mountain building, erosion, opening South America. of post-Permian modern oceans, and the production of new water The distribution of dinosaurs and ancestral Permian reptiles on at the mid-ocean ridges. an expanding Earth demonstrates the close links between Permian, These changes all modify the ancient coastal outlines and result Triassic and Jurassic species. This link was then disrupted in the by continental collision, on an expanding Earth they form by vertical uplift, creating plateaus. extremes. Triassic to Cretaceous dinosaurs plotted on expanding Earth models demonstrate that dinosaur distributions are clustered with- in three distinct provinces, coinciding with the distribution of ancestral Permian reptiles. These include distributions clustered in Europe and the Mediterranean region, in central and eastern North America, and in the adjacent South African and southern South American regions, with links to India. Isolated distribu- tions also occur in eastern Australia, southern China and western South America. The distribution of dinosaurs and ancestral Permian reptiles on an expanding Earth demonstrates the close links between Permian, Triassic and Jurassic species. This link was then disrupted in the APRIL —- MAY 2001 NEXUS = 55 Instead of mountains forming www. nexusmagazine.com