Kaledonische metamorphose der praekambrischen Charcot Land Serie, Scoresby Sund, Ost-Grönland

Abstract

The metamorphism of the Charcot Land sequence, a succession of sediments, extrusives, tuffs and gabbro and granite intrusions, is described. These rocks, of Precambrian age, rest on a gneissic basement, and are exposed in a tectonic window beneath a Caledonian thrust sheet. One principal metamorphic phase is distinguished, succeeded by a very weak retrograde phase. Locally around the gabbro intrusions traces of contact metamorphism are recorded. The metamorphic assemblages in the tuffs and gabbros, the siliceous dolomites, and the quartzites and mica schists are described and illustrated separately. A progressive northerly increase in metamorphic grade is revealed, the isograds occurring in roughly concentric arcs around a centre in the northern part of the area. Recrystallisation took place under temperature and pressure conditions of Barrovian type, and is probably Caledonian in age.