Abstract In the North Atlantic, Laurentia–Eurasia break-up commenced in the Late Carboniferous, largely following the structural grain of the Caledonian Fold Belt. However, in the Arctic region, a 45° offset in the plate boundary between North Greenland and Svalbard was determined by a number of pre-Caledonian fundamental faults in North Greenland. As a result, this segment of the plate boundary experienced significant episodes of combined transtension and transpression, in part controlled by the movement of a temporarily independent Greenland Plate. Late Permian–Mesozoic deposits in the North Greenland Wandel Sea Basin record the plate-boundary history along this offset, in our view in a series of at least 20, variously disturbed, pull-apart basins, most of which can be assigned to four major episodes of pull-apart basin formation. The direction of the pre-existing fundamental faults, in combination with the regional variation in rock properties of both the basin floor and basin fill, explains the marked differences in tectonic style recorded along the plate boundary.

Abstract The military environment of the post–World War II years was dominated by the principal threat of air and missile attacks over polar routes between North America and the former Soviet Union. The extremities of the arctic environment demanded unique adaptations to normal military operations, which provided military and engineering geologists an opportunity to exercise a broad range of technical applications. New knowledge and skills in ice physics and engineering, glaciology, arctic geomorphology, meteorology, oceanography, and permafrost engineering were all relevant, often requiring on-the-job learning. Such adaptability could be needed in the future and would once again challenge military geologists.