Styles of Trench‐Parallel Mid‐Ocean Ridge Subduction Affect Cenozoic Geological Evolution in Circum‐Pacific Continental Margins

Abstract

AbstractDistinct signatures are present in the circum‐Pacific continental margins (e.g., kinematics, magmatism, and basin evolution), possibly influenced by the input of mid‐ocean ridge. It remains enigmatic why the circum‐Pacific continental margins that have experienced trench‐parallel mid‐ocean ridge subduction show diverse geological evolution. Here we present geodynamic modeling results investigating trench‐parallel mid‐ocean ridge subduction and demonstrate two distinct types of model evolution. Type‐Ⅰ model includes a two‐stage steep subduction and is featured by slab detachment preceding the arrival of ridge at the trench. Type‐Ⅱ model is marked by a continuous flat subduction of mid‐ocean ridge with the opening of a slab window beneath intracontinental lithosphere. These two subduction styles produce diverse tectono‐magmatic responses. Our results could explain the magmatic gap and forearc uplift during the Izanagi‐Pacific ridge subduction and the intraplate magmatic flare‐ups and tectonic uplift during the Nazca‐Antarctic ridge subduction, respectively.