Burial metamorphic rocks from Fiji

Slow oxygen diffusion rates in igneous zircons from metamorphic rocks

Empirical tests of oxygen exchange rate in zircon crystals from amphiboliteand granulite-facies metamorphic rocks of the Grenville Province demonstrate preservation of igneous dO through protracted igneous and metamorphic histories, forming the basis of quantitative estimates of diffusion rate. Granitic orthogneisses, which cooled slowly after granulite-facies metamorphism, show no consistent r...

Groundwater in Sedimentary, Metamorphic and Volcanic Rocks

Fluorian garnets from the host rocks of the Skaergaard intrusion: Implications for metamorphic fluid composition

Zoned, silica-deficient, calcic garnets containing up to 5 mol% F substitution for 0 formed during contact metamorphism of basalts by the Skaergaard intrusion in East Greenland. Fluorian calcic garnets occur as a retrograde alteration of prograde wollastonite and clinopyroxene that fills vesicles and vugs in lavas 30-70 m from the intrusion. Paragenetically equivalent phases include fluorite, w...

Two types of tourmaline with igneous and metamorphic origin in metamorphic rocks of north Golpayegan, Isfahan province

The Muteh-Golpayegan metamorphic complex consist of different metamorphic rocks including pelitic, semi-pelitic, carbonate, quartz-feldspathic and basic metamorphosed rocks. The metapelitic rocks include chlorite schist, biotite schist, garnet schist, staurolite schist, kyanite schist, sillimanite schist and andalusite schist. The semi-pelitic rocks contain higher amounts of quartz and lower am...

Provenance and metamorphic evolution of high-pressure rocks from the Malpica-Tuy zone (MTZ) in NW Spain

An eclogite and its surrounding gneiss from the Malpica-Tuy zone, northwestern Spain, were studied. The eclogite contains besides garnet and omphacite, barroisitic amphibole, quartz, phengite with Si contents between 3.27 and 3.45 per formula unit (pfu), rutile, and accessory phases such as talc and (clino)zoisite-epidote. Garnet exhibits a chemical zonation with Alm59Prp13Grs24Sps4, Alm57Prp13...