Search results for "Glaucophane"
showing 3 items of 3 documents
On a peculiar metabasite in hercynian phyllites (sicily)
1976
On the basis of a mineralogical, petrological and chemical study of a “greenstone” complex intercalated in a phyllitic formation in the Western Peloritani Mountains, two main rock types can be distinguished: amphibole-chlorite metabasite (with traces of an old generation of glaucophane), and albite metabasite. The two rock types show considerable differences in composition, a consequence of sodium metasomatism. The study indicates that the greenstone complex is a metaspilite.
40Ar/39Ar laser probe dating of detrital white micas from Cretaceous sedimentary rocks of the Eastern Alps: Evidence for Variscan high-pressure metam…
1997
The detritus of Cretaceous synorogenic sandstones of the northern margin of the Austroalpine microplate contains evidence for a high-pressure metamorphic basement and obducted oceanic crust exposed in early Alpine time. 40 Ar/ 39 Ar laser-probe data of detrital white micas give excellent plateau ages in a narrow range from 320 to 360 Ma. White micas cover the whole range from muscovites up to phengites (3.04 to 3.48 Si per formula unit). Heavy mineral spectra contain chrome spinel, glaucophane, chloritoid, epidote, and garnet, as well as zircon, tourmaline, and rutile. Glaucophane, chloritoid, and phengite correlate in their abundance. These minerals also correlate positively with the stabl…
Radial cracks around α-quartz inclusions in almandine: Constraints on the metamorphic history of the Oman mountains
1993
Radiating tensional cracks around α-quartz inclusions in almandine have been observed in metapelite samples from the southeastern Saih Hatat tectonic window, northeastern Oman Mountains. These almandines show an inclusion-rich (glaucophane + epidote) and strongly deformed core with inclusions of different mineral phases. The rim of the same almandines is inclusion-poor and shows only quartz, apatite, zircon, rutile and BaAl phosphates as inclusions. Quartz and apatite inclusions in the rim are single crystals often surrounded by radial cracks. These radial cracks developed during uplift by the dilation of α-quartz (4–5 vol%) without a phase transformation. Subsequently, these cracks were fi…