WebBanff and Buchan Districts The stability field of andalusite occurs at pressures less than 0.37 GPa (~ 10 km), while kyanite →sillimanite at the ... – Low P/T Buchan-type of regional orogenic metamorphism – Dominant meta-pelitic sediments, and isograds up to the sillimanite zone have been mapped Buchan metamorphism occurs often in extensional settings, for example at rift basins. In contact metamorphism (metamorphism caused by high temperatures at low pressure in the vicinity of an igneous intrusion) a local contact aureole of zones is formed around a heat source. See more In geology, a metamorphic zone is an area where, as a result of metamorphism, the same combination of minerals occur in the bedrock. These zones occur because most metamorphic minerals are only stable in certain … See more The type of metamorphic zones in a terrane are also determined by the form of metamorphism. This is dependent on the geodynamic (tectonic and magmatic) setting in which metamorphism took place. The sequence of metamorphic zones is called a metamorphic … See more The temperature and pressure at which the mineralogical composition of a rock equilibrated can vary laterally through a metamorphic See more • Metamorphism • Metamorphic facies • Anatexis See more

A case of regional metamorphism of Buchan type (andalusite …

WebBuchan type anatectic metamorphism under upper amphibolite to granulite facies conditions in the adalusite to sillimanite stability fields. As generalized by Zheng and his colleagues, material ... WebRegional metamorphic zones, based on mineral assemblages in pelites, are presented for the Dalradian rocks of Aberdeenshire and Banffshire, in the type area of Buchan metamorphism; electron microprobe analyses of cordierite (C), staurolite (S), chlorite (Chl), biotite (B) and white mica (Ms) are reported for rocks from the classic sections of the … pip install xelatex

Barrovian and Buchan metamorphic series in the Chinese Altai: …

WebMany of the “type” areas for regional metamorphism have been only cursorily studied in this respect. For some years the difference between Buchan and Barrovian types was ascribed to the relative age of metamorphism and deformation, the Barrovian type being regarded as syntectonic crystallization and the Buchan type as post-tectonic ... WebThese pronounced differences in the type of metamorphism may be reflections of different times as well as different physical conditions of metamorphism. ... Vermont is a hornfelsic, "regional-contact" metamorphosed terrane more typical of the low-pressure intermediate, or Buchan, facies series of Miyashiro (1961). ... WebIt can also be separated into Barrovian- or Buchan-type metamorphism, according to the pressure-temperature gradients recorded in the rocks. Contact metamorphism. Contact metamorphism occurs typically around igneous intrusive rocks, as a result of the temperature increased caused by the igneous body. ... pip install wx报错