CPT Q. 047: How does CPT explain the closing of the Iapetus Ocean and origin of the Appalachians?

Q. 47. Catastrophic Plate Tectonics (CPT) not only distinguishes itself from Uniformitarian Plate Tectonics (UPT) in terms of time-scale reduction facilitated by subduction-rate acceleration, but would also appear to reject UPT’s foundational concept of ocean-basin and supercontinent formation—the Wilson cycle. Driven by the heat of radioactive decay, this essential UPT process relies on subduction zones flanking continental rifting to each oppose the plate motions of the divergent land mass, thereby closing an ocean basin and rejoining the separated supercontinent. Even though uniformitarians believe that this cycle averages 600 million years in duration and has occurred at least a half-a-dozen times since the alleged Precambrian, am I correct in assuming that CPT’s runaway subduction process would allow for only the first half of only one Wilson cycle due to its being a one-way, irreversibly-downward, mantle-directed mechanism? If this is the case, how does CPT explain the origin of the Appalachian Mountains which UPT claims is the indisputable result of a Wilson cycle involving Mid-Silurian continental collision to form this orogenic belt, thereby closing up the Iapetus Oceanic Basin, the precursor to today’s Atlantic Ocean (supposedly now in the third of the six stages of the Wilson cycle— Embryonic, Youth, Adolescence, Maturity, Old Age, Death)?

Response: As I indicated in my answer to question 46, the observational evidence for the opening and closing of the Iapetus Ocean and the associated tectonic signature in the continental rock record, including the Appalachian orogeny, is close to indisputable. Moreover, because of the presence of abundant metazoan fossils in the associated continental sediments, this spectacular tectonic activity must be part of the Flood cataclysm. As I also indicated in that answer, for such large-scale tectonic change to occur during the short time span of the Flood seems to require that the strength of the mantle to have been orders of magnitude smaller than it is currently. Hence, as I indicated in that answer, based on the observational evidence, “Wilson cycle” behavior, at least in the case of the Iapetus Ocean, logically must be part of the CPT description for the Flood.

Your question as to the mechanics of how this can happen is a valid one. My response to that is that the primary driving forces for plate motions over the earth’s surface are buoyancy anomalies in the mantle. Slabs of cold oceanic lithosphere represent one important type of buoyancy anomaly. Hot blobs of rock from near the core-mantle boundary represent the other important type. Based on previous 3D numerical experiments, I am convinced that the most of the possible initial thermal states for the mantle that will yield the sort of “Wilson cycle” type motions required for the three continental blocks, Laurentia, Baltica, and Siberia in a CPT scenario for the Flood are relatively complex and not that easy to guess or even find by a trial and error process. Nevertheless, I believe a trial and error approach might eventually succeed. Good candidate initial thermal states should probably include zones of cold rock in the upper mantle and zones of hot rock just above the core mantle boundary. My present conjecture is that an initial state consisting of a zone of cold rock around much of the perimeter of the Pannotia supercontinent plus a volume of hot rock just above the core mantle boundary beneath the northwestern portion of Pannotia might be a good point to begin the quest to find viable candidates. The CPT scenario, of course, would rely on gravitational potential energy stored in this initial temperature state and not on heat from decay of radioactive elements. Please see my response to question 95 below for details on the geological observations that so strongly support the reality of the opening and subsequent closing of the Iapetus Ocean.