Pegmatites of the Larvik Plutonic Complex, Oslo Rift, Norway: field relations and characterisation

Øyvind Sunde,Tom Andersen,Henrik Friis

doi:10.17850/njg99-1-05

Abstract

Pegmatites of the Larvik Plutonic Complex, Oslo Rift, Norway: field relations and characterisation

Highlights

Pegmatites associated with granitic systems have been extensively studied since the 19th century (e.g., Jahns & Burnham, 1969; Ĉerný, 1991; London, 2008)
Alkaline pegmatites tend to occur within their source pluton and rarely intrude deep into country rocks, whereas granitic pegmatites are typically emplaced outside their granitic source
Alkaline pegmatites occurring in the Larvik Plutonic Complex (LPC) represent a wide range of mineral assemblages described as miaskitic or agpaitic

Summary

Introduction

Pegmatites associated with granitic systems have been extensively studied since the 19th century (e.g., Jahns & Burnham, 1969; Ĉerný, 1991; London, 2008). Alkaline pegmatites tend to crystallise early liquidus assemblages containing high field strength elements (HFSE) such as Na–Zr silicates and show extensive late magmatic alteration of primary feltspathoids (Brøgger, 1890; Vlasov et al, 1966; Sørensen, 1967). Descriptive work on alkaline pegmatites and their mineral assemblages from the Lovozero, Khibina and Ilímaussaq intrusions have been carried out since the 19th century (e.g., Ussing, 1912; Fersman, 1926; Sørensen, 1967).

Objectives

Discussion

Conclusion