The Arctic Islands

Abstract

The Canadian Arctic Archipelago, perched on the northern rim of the continent, is about 1.3 million km2 in area, including intervening waters (Fig. 1; Plate 9, index). Parry Channel, a seaway connecting Baffin Bay with the western Arctic Ocean, separates the Queen Elizebeth Islands to the north from another group of islands to the south. Rugged mountain ranges with extensive ice caps in the eastern part of the archipelago, and plateaus, lowlands, and a coastal plain in the western part, are all dissected by numerous channels and fiords (Dawes and Christie, Ch. 3).1 Outlines of the geography and rudiments of the geology were established during the last century and the first half of this century. This work was done by ship, with sledges, or on foot, under hardship and often tragic circumstances (Christie and Dawes, Ch. 2). A coherent stratigraphic-structural framework has emerged from subsequent systematic surface studies, which have been supported by helicopters since 1955. Paleontology, always at the forefront of Arctic earth science, has provided the basis for both regional correlations and reconstructions of the geologic history. Petroleum exploration has been active in the islands since the early 1960s, and by 1987, 176 wells had been drilled and more than 65,000 km of seismic reflection lines had been shot. The well data have been absorbed into the stratigraphic framework, and a few instructive seismic interpretations have been released (e.g., Harrison and Bally, 1988), but the bulk of the seismic work remains unpublished. Gravity surveys (Sobczak, Ch. 5A) and deep seismic refraction surveys, both carried out from the late 1950s onward, have permitted construction of crustal cross sections in the western parts of the islands (Sweeney and others, 1986; Sobczak and others, Ch. 5B), while aeromagnetic surveys (Coles, Ch. 5D), electrical conductivity studies (Niblett and Kurtz, Ch. 5E), and analyses of seismicity (Forsyth and others, Ch. 5C) have elucidated other aspects of crustal structure and tectonics.

Crustal structure of the Innuitian region of Arctic Canada and Greenland from gravity modelling: implications for the Palaeogene Eurekan orogen

“…A passive continental margin (the Franklinian Margin) lay along the Precambrian craton by latest Proterozoic–Early Palaeozoic times and subsequently ‘closed’ during Devonian orogenesis. Trettin (1989) divided the Palaeozoic record of the Innuitian Region into regional successions. These are Late Neoproterozoic–Cambrian and younger carbonate rocks of the Arctic Platform and the Cambrian–Devonian aged successions of the shelf and deep‐water ‘provinces’, the former dominated by carbonate sequences and the latter subdivided into sedimentary and volcano‐sedimentary sequences.…”

Polyphase deformation at the Harder Fjord Fault Zone (North Greenland)

“…Trettin & Balkwill, 1979;Higgins, Friderichsen & Soper, 1981;Trettin, 1991) which is characterized by a northwards increase in deformation and metamorphism (e.g. Trettin, 1989;Surlyk, 1991). In the extreme north of North Greenland, three stages of deformation can be observed (e.g.…”

Blueschist facies metamorphism in Nordenskiöld Land of west‐central Svalbard

“…Their remnants are presently scarce because they must have been subsequently overprinted by continental collision, eroded and, as discussed below, dismembered by strike-slip displacements. The most likely counterpart to southwestern Svalbard is the Pearya Terrane of northern Ellesmere Island (e.g., Gee and Tebenkov, 2004;Mazur et al, 2009), where a Mesoproterozoic basement complex covered by Neoprotorezoic shallow (glacio)marine successions is overthrust by an Early Ordovician ophiolite and calcalkaline volcanics (Trettin, 1989). This dismembered ophiolite is unconformably overlain by Ordovician and Silurian carbonates, turbidites and volcanics.…”

“…ophiolite occurred prior to c. 460 Ma (Trettin, 1989). Early Permian plate reconstruction shows Svalbard located to the north of Greenland at the same latitude as the Pearya Terrane (Fig.…”