John Baumgardner, jrbaumgardner@liberty.edu
Baumgardner, J.R. 1986. Numerical Simulation of the Large-Scale Tectonic Changes Accompanying the Flood. In R. E. Walsh, C. L. Brooks, and R. S. Crowell (editors), Proceedings of the First International Conference on Creationism, pp. 17–30. Pittsburgh, Pennsylvania: Creation Science Fellowship.
This paper, presented at the very first ICC in 1986, was the initial publication proposing that the Flood was a tectonic catastrophe driven by runaway subduction of oceanic plates into the earth’s mantle. As such, it outlined the basic concepts for the framework that has since become known as catastrophic plate tectonics.
As the author, how do I view this paper 35 years later? First of all, I am grateful to God that he allowed me to avoid any gigantic blunders in this initial publication. The foundational observation providing the underpinnings of the paper is that all of today’s igneous ocean crust has formed since the onset of the Flood via the process of seafloor spreading as oceanic plates migrated apart. Assuming no major change in the earth’s radius, this observation implies that at least 60% of the earth’s surface area must have cycled into the earth’s interior during the year of the Flood. This simple logic—apart from any other consideration—represents the basis of catastrophic plate tectonics. The paper includes an exploration of the basic mechanics and heat/energy budget involved. The analysis shows that oceanic plates have sufficient extra density, because of its low temperature relative to the rock in the mantle beneath, to be on the verge of runaway instability were the mantle merely a bit warmer. It further shows that the gravitational potential energy associated with the layer of cold ocean floor rock is more than sufficient to drive a mechanical mantle overturn. All these estimates and conclusions still hold 35 years later. The analysis of viscosity reduction from deformational heating introduces the issue of how silicate minerals weaken under increased temperature and stress. That issue has been a major focus of my subsequent research and publications.
Because of the glaring conflict between the Bible’s account of world history and the time scale provided by secular radioisotope dating methods, I include a section on what I suspected to be the fundamental flaw of the secular methods, namely, the assumption of time-invariant nuclear decay rates, drawing heavily on the work of Robert Gentry. The conclusions I offer match closely those of the RATE team later published in 2005.
Finally, I emphasize my earnest conviction that the Flood cannot be explained or modeled purely in terms of time-invariant or uniformitarian physics. In other words, God’s supernatural intervention during the Flood in the laws He ordained appears to be unavoidably required. Specifically, such intervention seems to be demanded to account for an episode of accelerated nuclear decay as well as to cool today’s ocean floor to its present state. That cooling is essential to lower the global sea level by some 1,500 m and allow the water to drain from the continents.
What did I get wrong in the paper? Probably my most serious mistake was failing to pay heed to the vast amount of new seafloor creation during the Cenozoic portion of the geological record which allowed me to place the end of the runaway and hence the end of the Flood at the end of the Mesozoic. I deeply regret that error. Much less serious was my conjecture that the pre-Flood mantle would need to be somewhat warmer than it is today for the runaway instability to occur. With better understanding of how silicate minerals weaken under stress, I no longer conclude that necessarily to be the case. Further, I am now aware that the Sierra Nevada granites are a complex of pancake-shaped sills, as opposed to a large coherent batholith, that plausibly might be able to cool via normal hydrothermal processes during the time since the Flood. Finally, I regret the several typographical mistakes that somehow were missed in editing. Overall, I am grateful this paper has endured this test of time and scrutiny by my peers.
Seismic images display a ring of rock (shown above in blue) at the bottom of the mantle with much higher-than-average seismic speed. The most likely explanation for the higher seismic speed is lower temperature. This ring of rock lies beneath the major zones where ocean plates have plunged into the mantle in the past. The low temperature in this ring of rock suggests it corresponds to subducted surface rock that has sunk to the base of the mantle. The red features in the images above appear to represent hot rock that has been shoved aside by the cold rock from above. The inferred temperature difference between the red and blue regions is on the order of 3,000 °C. However, the temperature at the core-mantle boundary is estimated to be no more than 3,500-4,000 °C. Hence, the temperature in the blue ring of rock is not appreciably different from the average temperature of today’s oceanic plates. Such low temperatures are inexplicable in terms of a time scale of 50-100 million years that the secular framework requires for subducted surface rock to sink to the bottom of the mantle. However, they are powerful support for an episode of global catastrophic plate tectonics that occurred only a few thousand years ago.