Decoding the pressure–temperature–time (P–T–t) record of Archean polymetamorphic terranes

Abstract

By investigating the metamorphic record of ancient crustal rocks, this thesis aims to elucidate the conditions and timing of metamorphism on the early Earth (4.5–2.5 billion years ago). To decode the pressure–temperature–time (P–T–t) record of three Archean polymetamorphic terranes in Canada and southern India, this work integrates novel in situ garnet Lu–Hf geochronology with phase equilibrium modelling, providing robust constraints on the complex tectonothermal histories of these terranes.