نتایج جستجو برای: granulite

تعداد نتایج: 412  

Journal: :Geochemistry Geophysics Geosystems 2023

Exposures on Holsnøy island (Bergen Arcs, Norway) indicate fluid infiltration through fractures into a dry, metastable granulite, which triggered kinetically delayed eclogitization, transient weakening during fluid-rock interaction, and formation of shear zones that widened shearing. It remains unclear whether the effects grain boundary-assisted aqueous inflow duration granulite hydration were ...

Journal: :Journal of Geophysical Research: Solid Earth 2006

2004
J. W. Valley

Akermanite (Akg0) coexists with monticellite (Mo92) and wollastonite (Wo99) in an unusual calc-silicate xenolith in anorthosite at Cascade Slide in the Adirondack Mountains, New York. Experimental results bearing on the stability of akermanite have been evaluated through calculations based on thermochemical data and by chemical analysis of experimental products (Yoder 1975). A temperature of 75...

2004
K. Mezger

Based on lithological, structural and geophysical characteristics, the Proterozoic Grenville Orogen of southern Ontario and New York has been divided into domains that are separated from each other by ductile shear zones. In order to constrain the timing of metamorphism, U-Pb ages were determined on metamorphic and igneous sphenes from marbles, calc-silicate gneisses, amphibolites, granitoids, ...

2004
Jianping Zheng Fengxiang Lu Chunyang Wang Fangzheng Wang Huimin Li

U-Pb and Hf isotope analyses of zircons from felsic granulite xenoliths in Mesozoic volcanics reveal Early Archean ($3.6 Ga) lower crust beneath the younger (,2.85 Ga) southern margin of the North China craton, and suggest that the eastern part of the craton formed a coherent block by 3.6 Ga. Hf model ages indicate extraction of protoliths from the mantle ca. 4 Ga or earlier, followed by remelt...

2002
Roger L. Gibson W. Uwe Reimold Andrew J. Ashley Christian Koeberl

A new model is proposed to explain the origin of enigmatic fine-grained granulite facies rocks sampled from the Moon, based on observations from the Vredefort dome, South Africa. The dome is the deeply eroded central uplift of the ;300-km-diameter Vredefort impact structure. In the dome, fine-grained granulites displaying poikilitic or granoblastic microstructures were formed by relatively slow...

2007

Temperature estimates obtained with various biotite-garnet thermometers are inconsistent in granulite facies rocks. Although the inconsistency lies partly in the lack of definition of equilibrium criteria, it still remains after rigorous selection of analyzed mineral pairs (isolated biotite and garnet cores for peak equilibrium conditions) and originate from minor element effects in garnet and ...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید