for a time in the very latest neo-Proterozoic (560 Ma in terms of the secular time scale). In the time frame of the Flood this corresponds to very soon after the breakup of a pre-Flood supercontinent. Some, including the authors of this paper and Scotese, refer to the supercontinent as Pannotia. Others, including Blakey, refer to it as Rodinia. Note that the continental blocks Laurentia, corresponding to North America and Greenland, Baltica, corresponding to modern Western Europe, and Siberia, corresponding to Eastern Europe, have broken away from the rest of Pannotia, known as Gondwana, in a northerly direction. Although not shown explicitly in these maps, Gondwana consists of modern South America, Africa, Madagascar, India, Australia, and Antarctica as well as blocks that later become modern China and other portions of modern Asia. It is important to note that Gondwana, apart from the terranes that become modern China, persists intact throughout the Paleozoic to become part of Pangea. Fig. 3 (b)-(d) are successive snapshots in time from Blakey’s set of global paleogeography maps, snapshots that span most of the Paleozoic era. These show Laurentia, Baltica, and Siberia first moving away from the rest of Pannotia and from one another (b). They then show Laurentia and Baltica reversing directions relative to one another and colliding back together (c). Finally, they show the remainder of Pannotia moving northward in the eastern hemisphere, across the South Pole, and colliding with Laurentia/Baltica from the south and that assembly colliding with Siberia also from the south (d). A major difference between the paleogeographical reconstruction of Scotese and that of Blakey involves a large displacement of Laurentia, Baltica, and Siberia relative to Gondwana during the early Paleozoic in Blakey’s reconstruction as the three breakaway blocks come back together and rejoin Gondwana. That displacement is not that obvious in the plots of Fig. 3. The reconstruction by Scotese, however, eliminates this displacement entirely by having the initial locations of the three breakaway blocks in Pannotia relative to Gondwana the same as after they rejoin. Choosing these aspects of the Scotese reconstruction, as we choose to do, significantly reduces the required amount of Paleozoic subduction. One can inquire as to the reliability of continent motion reconstructions such as those of Blakey and Scotese. My own assessment is that the basic features are robust. They are based on vast numbers of paleomagnetic determinations stretching back more than 60 years by many investigators for all the continents. They are also based on a vast amount of geological field observation, including indisputable evidence for continent-continent collisions during the Paleozoic and associated orogenies, for example, the Caledonian orogeny involving Europe and North America, the Variscan/Hercynian/Appalachian orogeny involving Europe, North America, and Africa, and the Uralian orogeny involving Europe and Asia/Siberia. While details remain uncertain, to us as authors there is little reason to question this overall displacement history. C. The issue of polar wander But what about the inferred 110° of motion relative to today’s North Pole, not only for North America and Europe, but also for all of the other continental blocks since the beginning of the Paleozoic? In terms of the Biblical framework with its clear account of a global Flood cataclysm, it is nigh to impossible to conceive of all the continents migrating across the face of the earth, more or less in synchrony, for more than a quarter of the earth’s circumference during the few months of the Flood. A much simpler explanation instead is that a change in the orientation of the earth’s magnetic poles relative to the continents occurred during that interval, a Figure 3. Selections from Ronald Blakey’s (2008) set of global paleogeographic maps for times, in terms of the secular geological time scale, of 560 Ma (a), 450 Ma (b), 400 Ma (c), and 300 Ma (d). These snapshots show the breakaway of three continental block from the late Neoproterozoic supercontinent Pannotia and their subsequent re-amalgamation to form the early Mesozoic supercontinent Pangea. BAUMGARDNER AND NAVARRO Large tsunamis and Flood sediment record 2023 ICC 369
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