Austrheim, H. and Griffin, W.L., 1985. Shear deformation and eclogite formation within granulite-facies anorthosites of the Bergen Arcs, western Norway. In: D.C. Smith, G. Franz and D. Gebauer (Guest-Editors), Chemistry and Petrology of Eciogites. Chem. Geol., 50: 267—281.

The anorthosites of the Bergen Arcs contain two distinct metamorphic mineral assemblages which are stable under different P—T conditions. A granulite-facies assemblage, which equilibrated at T = 800—900° C, P < 10 kbar, is defined by the minerals plagioclase, Al-rich diopside (Cpx I), garnet (Gnt I) ± scapolite ± orthopyroxene + dark-brown hornblende. This assemblage is linked by corona structures to a primary mag-matic mineralogy, where coexistence of olivine and plagioclase limits the maximum crystallization pressure of the anorthosites to ~ 8 kbar at 1200°C. The anorthosites are transected by a series of fine-grained shear zones in which the granulite-facies assemblage is replaced by an eclogite mineralogy defined by omphacite (Cpx II) (Jd40_i0) + garnet + kyanite + epidote/clinozoisite + phengite + quartz ± amphibole with plagioclase sometimes remaining in the marginal parts. Mineral compositions indicate equilibration conditions for the eclogite paragenesis of Г = 700—800° С, Р = 16—19 kbar.