Planetesimal accretion during planet formation is usually treated as collisionless. Such accretion from a uniform and dynamically cold disk predicts protoplanets with slow retrograde rotation. However, if the building blocks of protoplanets, planetesimals, are small, of order of a meter in size, then they are likely to collide within the protoplanet’s sphere of gravitational influence, creating...

Eclogites from the Guanshan and Yangkou areas of Sulu orogen consist garnet, omphacite, phengite, amphibole, quartz/coesite, rutile, ilmenite. Garnet exhibits weak compositional zoning where Xgr decreases core to mantle then increases towards rim, coupled with an increase in Xpy decrease rim. Phase equilibria modelling pseudosections calculated using THERMOCALC NCKFMASHTO system for eclogites r...

Ophiolites of the Alpine belt derive from closure Mesozoic Tethys Ocean that was interposed between palaeo-Europe and palaeo-Adria continental plates. The orogeny has intensely reworked oceanic rocks into metaophiolites with various metamorphic imprints. In Western Alps, continental-derived units are distributed within two paired bands: An inner band where subduction-related high-pressure (HP) ...

The preserved Archean continental crust is dominantly comprised of tonalite-trondhjemite-granodiorite (TTG) suites associated with less abundant low-grade greenstone belts. exact processes that form TTGs, as well the source rock they are derived from, difficult to constrain from sparse geological record. However, studies show water-present partial melting metamorphosed basalt at temperatures 75...

Archean supracrustal sequences of pelitic, quartzitic, calcareous and mafic compositions in the central Laramie Mountains, Wyoming, have been affected by two metamorphic events: a 1.78 Ga amphibolitegrade regional metamorphism, and a 1.43 Ga contact metamorphism resulting from the intrusion of the Laramie Anorthosite Complex (LAC). Rb–Sr whole-rock isotopic data from both outside and within the...

This work evaluates an exceptionally complex natural laboratory, the Middle Triassic Latemar isolated platform in northern Italian Dolomite Mountains and explores spatial temporal gradients processes products related to contact metamorphism, dolomitization dedolomitization of marine limestones. The relation between petrographic change re-equilibration geochemical proxy data is evaluated from pe...

Empirical studies of zircon in migmatites document features compatible with growth during heating at suprasolidus conditions. However, numerical modelling behaviour suggests that is expected to grow only cooling and melt crystallization. Here, phase equilibrium coupled mineral–melt Zr partitioning used an attempt reconcile the observations from predictions previous models anatectic systems. In ...

Thallium (Tl) is a highly incompatible element which can be redistributed during various igneous and hydrothermal events such as mineral dehydration low-temperature alteration. Despite the strong influence fluid-rock interactions have on Tl redistribution importance of fluids in subduction-zone volatiles cycling, geochemical behavior high-P/T metamorphism has not yet been quantified. Here we pr...