A trans-Iapetus transform fault control for the evolution of the Rheic Ocean: Implications for an early Paleozoic transition of accretionary tectonics: Comment

The premise put forth by Wu et al. (2022) that the late Proterozoic and early Paleozoic development of the Appalachian Orogen was controlled by transform faults finds no support in the geology of the region. Such faults have been well studied on and offshore over the past century and a quarter by many federal and private agencies because of the seismic hazard they pose to nuclear power plants and dams and their significance in offshore exploration. The northwest-trending transform faults developed in the Middle Jurassic across early oceanic crust as the Atlantic Basin began to open, to offset the initial northeast-trending Late Triassic–Early Jurassic rifts and extended landward. These young transform faults, which were accompanied by north-trending rifts, could have played no part in the development of the Appalachian Orogen, Laurentia, Iapetus, or the Rheic Ocean. Furthermore, the presented plate reconstructions cannot be reconciled with the well-controlled geologic history revealed in southern New England (USA), where the Appalachian Collision Zone is exposed. Relations there demonstrate that northwest Africa and Laurentia had first collided during the late Proterozoic Pan African Orogeny, long before the times shown on the reconstructions by Wu et al. (2022).