A seismic array consisting of nine Hawaii Institute of Geophysics (HIG) ocean bottom seismometers (OBSs) was deployed at the eastern intersection of the Oceanographer Fracture Zone (OFZ) and the Mid-Atlantic Ridge (MAR). The 12-day experiment was designed to relate low-magnitude earthquakes to the structure and tectonics of the MAR-OFZ intersection. An average of 10 locatable events with duration-based magnitudes between -1.0 and 2.0 were recorded per day. Excellent hypocentral locations of 112 events were obtained. Earthquake locations based on more than eight observations generally show 50% confidence volume constraints within OBS location errors. The earthquake locations cover a broad swath across the corner of the intersection zone. Magnitude-weighted earthquake location likelihood maps suggest a decline in magnitudes near the intersection bathymetry low. Composite focal plane solutions suggest source mechanisms which indicate that the region is dominated by extensional tectonics. Alternative source solutions indicating translational movement are presented but are inconsistent with apparent bathymetric trends. The transition from the diverging (MAR) to translational (OFZ) plate margin occurs in the context of reduced magma genesis and crustal thinning due to the influence of the adjacent older lithosphere. The region may be described in terms of semirigid plate tectonics accompanying transform valley genesis.