Twenty-eight earthquakes in the Baffin Bay region have been relocated using the method of Joint Hypocenter Determination. The revised locations indicate two parallel, linear trends, one along the northeast coast of Baffin Island and the other in the western part of Baffin Bay. The seismicity does not appear to be controlled by glacial rebound but may be a remnant of sea-floor spreading which occurred 40 to 60 m.y. ago. Early P arrivals at near seismograph stations (Δ < 20°) can be explained by a high-velocity (8.5 km/sec) upper mantle in the Baffin region.