The Rogaland Intrusive Massifs - an excursion guide

Abstract

The Rogaland Anorthosite Province comprises three major massif-type anortho- sites, two smaller-sized anorthositic-leuconoritic bodies, as well as a large layered, dominantly noritic intrusion. A Mangero-noritic intrusion is found in the northeastern part of the province and major acidic intrusions are located to the far southeast. The Rogaland Anorthosite Province was emplaced into the Sweconorwegian orogenic belt of southwest Scandinavia at 931+-3 Ma. Emplace- ment took place at around 5.5 kbar producing a thermal aureole with osumilite and evidence for dehydration melting. The early history of the hosting terrane most likely dates back to Gothian or late Pre-Gothian times and contain evidence for numerous episodes of folding and deformation. Contact metamorphism was superimposed on a crustal volume, which had been exposed to Sveconorwegian granulitic facies metamorphism 1024 amd 970 Ma.