Linking metamorphism and plate boundaries over the past 2 billion years

Abstract Since the Jurassic, there has been a clear spatiotemporal correlation between different types of metamorphism and active convergent plate margins. However, extent to which this relationship extends into past is poorly understood. We compared paleogeographic reconstructions inferred kinematics with age thermobaric ratio (temperature/pressure [T/P]) over 2 b.y. The null hypothesis—that no link margins metamorphism—can be rejected. Low-T/P almost exclusively located near margins, whereas intermediate- high-T/P skews toward increasingly greater distances from these consistent three tectonic settings: subduction zone, mountain belt, orogenic hinterland, respectively. suggest that so-called “paired metamorphic belts” are rare high- low-T/P localities more commonly occur along strike each other. observation bimodal largely function distance trench end-member T/P rarely in same place can explained if style orogenesis evolved hotter colder, abrupt emergence Cryogenian. widespread development rocks hinterlands Proterozoic was followed by production efficient exhumation channels Phanerozoic.