Metamorphic series include the Barrovian and Buchan series of

metamorphic rock Metamorphic rocks arise from the transformation of existing rock to new types of rock in a process called metamorphism. The original rock (protolith) is subjected to temperatures greater than and, often, elevated pressure of or more, causin ...

s. George Barrow was a geologist in Scotland who discovered the Barrovian series. These are also called metamorphic facies series. A

metamorphic facies A metamorphic facies is a set of mineral assemblages in metamorphic rocks formed under similar pressures and temperatures.Essentials of Geology, 3rd Edition, Stephen Marshak The assemblage is typical of what is formed in conditions corresponding ...

series is a sequence of metamorphic facies which plot in a temperature-pressure diagram along a line, and this line represents a certain geothermal gradient. They are not the same as

metamorphic zone 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 intervals of temperature and press ...

s, as these are defined as a region on a geological map where the pressure-temperature conditions for an

index mineral An index mineral is used in geology to determine the degree of metamorphism a rock has experienced. Depending on the original composition of and the pressure and temperature experienced by the protolith (parent rock), chemical reactions between mine ...

(a mineral that indicates the approximate metamorphic grade of a rock), were appropriate for these minerals to form. Al2SiO5_phase_diagram

* Buchan metamorphism has the facies series

greenschist Greenschists are metamorphic rocks that formed under the lowest temperatures and pressures usually produced by regional metamorphism, typically and 2–10 kilobars (). Greenschists commonly have an abundance of green minerals such as chlorite ...

amphibolite Amphibolite () is a metamorphic rock that contains amphibole, especially hornblende and actinolite, as well as plagioclase feldspar, but with little or no quartz. It is typically dark-colored and dense, with a weakly foliated or schistose (flaky ...

granulite Granulites are a class of high-grade metamorphic rocks of the granulite facies that have experienced high-temperature and moderate-pressure metamorphism. They are medium to coarse–grained and mainly composed of feldspars sometimes associated w ...

* Barrovian metamorphism has the same facies series but has approximately 1 kbar more pressure so these rocks form

kyanite Kyanite is a typically blue aluminosilicate mineral, found in aluminium-rich metamorphic pegmatites and sedimentary rock. It is the high pressure polymorph of andalusite and sillimanite, and the presence of kyanite in metamorphic rocks generally ...

Tulane University

References

{{reflist Geology Metamorphic rocks