Rb-Sr isotope systematics in metamorphic rocks,Kongsberg sector,south Norway |
| |
| Authors: | Stein B Jacobsen Knut S Heier |
| |
| Institution: | 1. Mineralogisk-Geologisk Museum, Sars Gate 1, Oslo 5, Norway;2. Mineralogisk-Geologisk Museum, Sars Gate 1, Oslo 5, Norway |
| |
| Abstract: | Rb-Sr isotope data are presented for gneisses, migmatite neosome material and granitic and gabbroic intrusive rocks from the southern part of the Kongsberg sector, south Norway. The maximum age of the crust in this area appears to be ～1.6 AE. Two metamorphic episodes at ～1.5–1.6 AE and at ～1.1–1.2 AE are recognized. Initial 87Sr/86Sr ratios for the granitic rocks give evidence for reworking of sialic crust and indicate that approximately 1.6 AE old crust repeatedly acted as a source for granitic magmas for a timespan of ～0.5 AE. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
