Geologic map of the Bergen Arcs Geological Survey of Norway http://www.ngu.no/

The area of Holsnoy with extensive eclogite development The area of Holsnoy with extensive eclogite development. Note that eclogite distribution is not controlled by lithology. Austrheim (1987) Fig. 1b

Granulite facies Eclogite facies The basic field relationship discussed in the paper: eclogite cuts (and is thus younger than) granulite-facies assemblages. Sometimes eclogite-facies shear zones follow granulite-facies folitaion, sometimes not. For discussion of Problem Set Question 2. Austrheim (1987) Fig. 7c

Shear zone For discussion of Problem Set Question 1. Winter, 2001

Metamorphism of the Bergen Arcs, Norway Density: ~3.2g/cm3 Density: ~3.0g/cm3 M1 For discussion of Problem Set Question 3. Winter, 2001

Holsnoy http://www.uwm.edu/People/tboundy/boundypub.html

All of the following images were taken by W. Peck on a gloomy (i. e All of the following images were taken by W. Peck on a gloomy (i.e. typical) day on the Norway coast. They show the progression of Eclogite formation. First, small shears host the eclogite. Shear zones get larger, and eventually the only granulites remaining are in isolated blocks within large shear zones. Contrast and brightness can be manipulated; I’ve set these images so that they project well but don’t look too ‘over-processed’.

Granulite: Plag+Opx Eclogite: Omphacite+Grt

Note deflection of granulite-facies foliation into shear zone.

Granulite Eclogite Sometimes the ‘eclogite front’ is parallel to granulite foliation

Eclogite Granulite

Granulite Eclogite A large shear zone cuts the base of this hill

Eclogite Granulite This block of granulite is surrounded by an eclogite-facies shear zone. Note the preservation of the granulite-facies foliation.

Eclogite Granulite Blocks of granulite in large elcogite shear

Granulite Eclogite