A major challenge for Flood geology is providing a credible explanation for how the staggering volume of fossil-bearing sediment was eroded, transported, and deposited in orderly patterns on the surface of the normally high-standing continents in only a few months’ time. This paper builds upon the numerical modeling work reported at the 2018 ICC utilizing a code named MABBUL which showed that repetitive giant tsunamis generated by catastrophic plate tectonics during the Genesis Flood can plausibly account for the Flood sediment record. That modeling demonstrated that, with reasonable parameter choices, tsunami-driven cavitation erosion during the Flood itself, mostly along the continent margins, can produce most of the sediment in today’s fossil-bearing record. The modeling showed further that tsunami-driven pulses of turbulent water can transport this sediment vast distances across the continental surfaces and that these hydrological processes generate sequences of laterally extensive layers often separated by erosional unconformities. That model incorporated a representation of the dynamic history of the continental blocks to explore the influence of continental motions during the cataclysm. It also included an initial continental topography, with low elevations along the coasts and higher elevations inland. Astonishingly, but not mentioned in the paper, the low-order sediment distribution generated in that model matched in a striking way the actual sediment distribution of today’s world. That computational study provided important insight regarding the primary source of the Flood water, how that water was able to cover the normally high-standing continent surface, what produced and sustained the water flow, the primary source of the sediment, the primary means of sediment transport and deposition across the continent surface, why little erosional channeling occurred between sediment layers, and the processes likely responsible for observed paleocurrent directions.
This paper focuses on the details of the actual generation of the continental sediment record by the complex pattern of tsunamis that invade the continent interior and interact with one another. The MABBUL model now includes a more accurate continent motion history and runs at double the horizontal spatial resolution with grid points spaced only 60 km apart. It also now accounts for an ever-increasing amount of newly produced ocean floor and a corresponding increase in global sea level. To model the erosional unconformities between mega-sequences in the continental sediment record, MABBUL now allows for sudden drops in sea level caused by episodes of cooling of the oceanic lithosphere. Probably the most exciting aspect of the oral presentation of this work at the ICC will be the high frame-rate movies of the tsunami dynamics as they interact with one another across the land surface to leave behind successive layers of new sediment.