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Elucidating the petrogenesis and geodynamic setting(s) of anorthosites in Archean layered intrusions and Tethyan ophiolites has significant implications for crustal evolution and growth throughout Earth history. Archean anorthosite‐bearing layered intrusions occur on every continent. Tethyan ophiolites occur in Europe, Africa, and Asia. In this contribution, the field, petrographic, petrological, and geochemical characteristics of 100 Tethyan anorthosite‐bearing ophiolites and 155 Archean anorthosite‐bearing layered intrusions are compared. Tethyan anorthosite‐bearing ophiolites range from Devonian to Paleocene in age are variably composite, contain anorthosites with highly calcic (An44–100) plagioclase and magmatic amphibole. These ophiolites formed predominantly at convergent plate margins, with some forming in mid‐ocean ridge, continental rift, and mantle plume settings. The predominantly convergent plate margin tectonic setting of Tethyan anorthosite‐bearing ophiolites is indicated by negative Nb and Ti anomalies and magmatic amphibole. Archean anorthosite‐bearing layered intrusions are Eoarchean to Neoarchean in age, have megacrystic anorthosites with highly calcic (An20–100) plagioclase and magmatic amphibole, and are interlayered with gabbros and leucogabbros and intrude pillow basalts. These Archean layered intrusions are interpreted to have predominantly formed at convergent plate margins, with the remainder forming in mantle plume, continental rift, oceanic plateau, postorogenic, anorogenic, mid‐ocean ridge, and passive continental margin settings. These layered intrusions predominantly crystallized from hydrous Ca‐ and Al‐rich tholeiitic magmas. The field, petrographic, and geochemical similarities between Archean and Tethyan anorthosites indicate that they were produced by similar geodynamic processes mainly in suprasubduction zone settings. We suggest that Archean anorthosite‐bearing layered intrusions and spatially associated greenstone belts represent dismembered subduction‐related Archean ophiolites. Key Points: Tethyan ophiolite‐hosted anorthosites are analogous to Archean anorthosites and both largely formed at oceanic convergent plate marginsArchean anorthosite‐bearing layered intrusions and associated greenstone belts are dismembered subduction‐related ophiolitesGeological characteristics of Archean terrains are consistent with the operation of plate tectonics since the Eoarchean [ABSTRACT FROM AUTHOR]

Assesses whether the assemblage of the Archean Schreiber-Hemlo greenstone belt in Superior Province, Canada, can be interpreted as an Archean tectonic melange using a combination of detailed structural mapping and geochemistry of sedimentary, volvanic and intrusive rocks. Information on Superior Province; Deformation phases and its relationship to the formation of a tectonic melange in the belt's Schreiber assemblage.

The article presents a study on Ophiolites which represents fragments of the ancient oceanic lithosphere. Topics discussed include the importance of ophiolites in determining the mechanism of the tectonic plates, global tectonic evolution and reconstruction of the supercontinent, Metamafic-ultramafic rocks commonly occurring as lenses and metamafic–ultramafic complex and metasupracrustalrocks combined into an ophiolitic mélange suffered paleoproterozoic amphibolitegranulite facies metamorphism.

The article discusses the Zanhuang tectonic mélange in the Zanhuang Massif of the Central Orogenic Belt in China which seperates the Eastern Block from an Archean arc terran. It is one of the best-preserved Archean tectonic mélanges in the world and contains complex tectonic mixture of metapsammites, quartzites mixed with volcanic rocks and metapelites. The article also presents diagrams of the kinematic framework in the mélange.

The article discusses a Neoarchean subduction polarity reversal event in the North China craton. It states that this event resulted in melting of the enriched mantle thereby giving rise to the intrusion of mafic dikes hence providing strong evidence that plate tectonics has operated by the end of the Neoarchean.

The article presents a study on the subduction initiation and generation of the Xigase ophiolite in Southern Tibet as of December 2015. Based on the composition of the Xigaze peridotites, the ophiolite are residues of partial melting and then modified by infiltration of light rare earth element (LREE)-enriched boninitic melts. It claims that the Xigase rocks belong to the Mid-Ocean-Ridge-Basalt (MORB)-like rocks and boninitic rocks.