The Fuchuan Ophiolite in South China: Evidence for Modern‐Style Plate Tectonics During Rodinia Breakup

Abstract

Earth is the only known planet with plate tectonics, which facilitates interaction between the lithosphere, hydrosphere, and atmosphere and has promoted the development of the biosphere. In the past few decades, however, proposed ages for the start of subduction span almost all of geological time before the Cambrian (Palin et al., 2020; and references therein). In recent years, plate tectonics sensu lato has been subdivided into modern-style and ancient-style (Zheng & Zhao, 2020). Modern-style plate tectonics is a response to cold and deep subduction (Stern, 2005;Zheng & Zhao, 2020), whereas the ancient-style is characterized by warm and shallow subduction related to bimodal geodynamic regimes (Palin et al., 2020;Zheng & Zhao, 2020). Modern-style plate tectonics is linked with secular cooling of the mantle, accompanied by changes in the buoyancy and rheology of ocean lithosphere, resulting in the horizontal motion of lithosphere and thus tectonic evolution similar to subduction (Cawood et al., 2018;Holder et al., 2019).Ophiolites, representing fragments of oceanic crust and lithospheric mantle, have been tectonically incorporated into continental margins and can provide essential insights into the evolution of seafloor spreading, slab subduction, and plate tectonics (Dilek & Furnes, 2011Khan et al., 2020). Well-preserved ophiolites are widespread throughout the Phanerozoic, but this is in contrast to the Precambrian where ophiolites