The Mogok Metamorphic Belt (MMB) in Myanmar is a polymetamorphic, mainly Paleogene granulite-uppermost amphibolite facies terrane consisting of marbles and calc-silicates hosting spinel, ruby sapphire. Jurassic charnockite-syenite intrusions, as well Eocene-Miocene leucogranite intrusions are also present. Pelitic rocks uncommon, where present, have sillimanite, both primary inclusions garnet s...

Mineral assemblages that are diagnostic of ultrahigh-temperature (>900 °C) metamorphism generally restricted to Mg- and Al-rich rocks. However, in many metamorphic terrains such compositions do not occur, the rocks dominated by orthogneisses typically contain high-variance mineral particular pressure–temperature (P–T) conditions. Here we use whole-rock chemistry, thermodynamic phase equilibrium...

Abstract Continental arcs in active continental margins (especially deep-seated arc magmatism, anatexis, and metamorphism) can be extremely significant evaluating continent building processes. In this contribution, a Paleozoic section is constructed based on coeval granulite-facies metamorphism, magmatism the northern margin of Qilian Block, which record two episodes crust growth. The deeper la...

We have deduced the steady-state lithospheric geotherm at c. 1 Ga in the south Indian shield area using the available data on the concentration of radioactive elements, and the f-T conditions of Proterozoic mantle xenoliths in the south Indian kimberlites as constraints. The geotherm was adjusted back to 2.5 Ga by keeping the surface temperature constant and calculating the temperature change a...

Abstract. Modern-style plate tectonics is characterised by the global operation of cold and deep subduction involving blueschist facies ultrahigh-pressure metamorphism. This has been a common process since Neoproterozoic, but couple studies indicate similar processes were active in Paleoproterozoic, at least on local scale. Particularly conspicuous are extreme conditions ∼ 7 GPa thermal gradien...

The Palaeoproterozoic Great Slave Lake shear zone (GSLsz) is a crustal-scale strike-slip structure, with total length of >1,000 km and width ~25 km, that separates the Archean Rae cratons. range metamorphic rocks now exposed at surface encompasses granulite facies mylonite through to lower-greenschist ultramylonite cataclasite, providing potential type example fault-zone structure in middle low...