The Kap Washington Group volcanics

Abstract

The Kap Washington Group volcanic rocks outcrop on the north coast of Johannes V. Jensen Land and Lockwood ø, where they are in thrust contact with Palaeozoic metasediments of the North Greenland fold belt. Their outcrop is limited, from west to east, to Lockwood Ø, Kap Kane, Kap Washington and Kap Cannon (fig. 21). The vo1canic rocks post-date basic dykes which cut Carboniferous and Permian sediments (Håkansson et al., this report) and their age, as determined by whole rock Rb-Sr isotopes in rhyolitic material, is 63 Ma (Larsen et al., 1978) i.e. early Tertiary. This is somewhat younger than the late Cretaceous age established by micropalaeontological evidence (D. Batten, personal communication) from shales, found in 1980, interbedded with the voicanics.