During the last 20 years much has been written about dinosaur paleobiogeography. This presents a challenge to creationists who wish to be consistent with the Bible and the evidence from paleontology, biogeography and geology.
Publications by evolutionists report that dinosaur fossils are first found in the Middle or early Late Triassic rocks of the Southern Hemisphere. The three major constituent clades, Ornithischia, Sauropodomorpha and Theropoda, are found in Late Triassic rocks and Early Jurassic rocks. There are also dinosaur footprints in Triassic, Jurassic and Cretaceous rocks. Middle to Late Jurassic and Cretaceous rocks contain the greatest diversity of dinosaurs. This diversification was associated with the appearance of various dinosaur kinds around the globe. It is thought that dinosaurs dispersed from the southern hemisphere across the globe as a result of movements of tectonic plates, via land bridges and across the sea.
The majority of creationists consider that these fossils and trackways were buried during the later stages of the global flood. This model requires the survival of dinosaurs during the cataclysmic onset of the flood and then for several months, before leaving footprints in newly deposited sediments. This would have to be repeated several times to account successive rock layers with footprints and fossils which must have been deposited while the whole Earth was covered with water. This appears highly improbable.
An alternative hypothesis is that the dinosaur fossils and dinosaur footprints, found in Mesozoic rocks, record the dispersal and diversification of the original dinosaur kinds which came off Noah’s ark. This post-flood model might allow time for the small number of dinosaur kinds to multiply and diversify as they spread across the globe. At the same time the break-up of Pangea resulted in repeated transgressions and regressions of the sea which produced the majority of the Mesozoic sediments. This is consistent with the evidence of increased diversity in later rocks which in a young Earth paradigm would have happened in a few 100 years after the flood. It also provides an explanation for stratomorphic series which seem unlikely within some commonly accepted models of flood geology.