A simplified plate kinematic model for the Paleogene motion of Greenland relative to North America has been developed to provide a new framework for modeling the oceanic spreading system in Baffin Bay and the intraplate tectonic development of the Davis Strait and Nares Strait regions of the Arctic. A single Euler rotation pole was calculated for the C13N to C24N Eocene motion of the Greenland Plate relative to North America using spreading centers and fracture zones interpreted from satellite derived gravity data in Baffin Bay combined with fracture zones in Labrador Sea from published sources. A single stage pole is proposed for the C25N to C27N portion of the Paleocene and a short‐lived stage pole was found necessary to accommodate the C24N to C25N interval. This kinematic model has been used to reinterpret published shipborne magnetic profiles in central Baffin Bay to reveal a Paleocene spreading center and limits of both Eocene and Paleocene oceanic crust. Aeromagnetic data over northeastern Baffin Bay have been used to identify a new fracture zone in northern Baffin Bay. Plate reconstructions are presented incorporating constraints on plate boundaries from onshore and offshore geological and geophysical mapping. Within the Davis Strait, Paleocene oceanic crust was emplaced in an elongated rift that was subsequently inverted by approximately 300 km of Eocene transpression along the Ungava Fault Zone. In the Nares Strait Region, a “microplate” scenario is presented to explain the simultaneous formation of the Lancaster Sound Rift Basin and complex deformation within the Eurekan Orogenic Belt.

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The Labrador Sea is a small oceanic basin that developed when the North American and Greenland plates separated. An initial period of stretching in Early Cretaceous time formed sedimentary basins now preserved under the continental shelves and around the margins of the oceanic crust. The basins subsided thermally during Late Cretaceous time and a second episode of tectonism took place during latest Cretaceous and early Paleocene time, before the onset of sea-floor spreading in mid-Paleocene time. Around the northern Labrador Sea, Davis Strait and in southern Baffin Bay, voluminous picrites and basalts were erupted at and shortly after the commencement of sea-floor spreading. Volcanism occurred again in early Eocene time at the same time as sea-floor spreading commenced in the northern North Atlantic. Farther southeast, along the Labrador and southern West Greenland margins, oceanic crust is separated from continental crust by highly stretched but non-magmatic transition zones which developed before sea-floor spreading. A complex transform zone, which developed during sea-floor spreading in late Paleocene and early Eocene time, separates continental and oceanic crust along the Baffin Island margin. The Greenland and Labrador ocean-continent transitions are asymmetric across the only available conjugate cross-sections. However, a cross-section through the Labrador margin farther north resembles the Greenland cross-section in the conjugate pair more than it does the Labrador cross-section of this pair. Consideration of the geological history of the area suggests that the non-magmatic transition zones may have formed by slow extension of a few millimetres per year through a period of 53 Ma during Cretaceous and early Paleocene time.

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