Metamorphic series

Metamorphic series include the Barrovian and Buchan series of metamorphic rocks. George Barrow was a geologist in Scotland who discovered the Barrovian series. These are also called metamorphic facies series. A metamorphic facies 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 zones, as these are defined as a region on a geological map where the pressure-temperature conditions for an index mineral, were appropriate for these minerals to form.

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