Open Access40Ar/39Ar mineral age constraints on the timing of deformation and metamorphism, North-East Greenland
Author(s) -
R. D. Dallmeyer,
R. A. Strachan
Publication year - 1994
Publication title -
rapport
Language(s) - English
Resource type - Journals
eISSN - 2597-2944
pISSN - 0418-6559
DOI - 10.34194/rapggu.v162.8257
Subject(s) - geology , metamorphism , gneiss , basement , proterozoic , devonian , geochemistry , mineral , geochronology , impact structure , paleontology , metamorphic rock , impact crater , tectonics , archaeology , geography , materials science , physics , astronomy , metallurgy
40Ar/39Ar mineral ages have been determined from basement gneisses and cover sequences exposed in the Caledonides of North-East Greenland. These range between c. 438 Ma and c. 370 Ma (Early Silurian – Middle Devonian). They are interpreted as dating cooling folIowing polyphase Caledonian metamorphism which completely rejuvenated intracrystalline argon systems within the (early Proterozoic) basement gneisses. The 40Ar/39Ar results indicate that thrust-related regional deformation.