Processed bathymetry data derived from an EM122 multibeam sonar survey that was conducted at the southern end of the Reykjanes Ridge, a segment of the Mid-Atlantic Ridge, in 2013 during Langseth cruise MGL1309 (investigators Fernando Martinez and Richard Hey). The data file is in netCDF:GMT grid format and was generated as part of the project called Test Between Thermal and Tectonic Hypotheses for North Atlantic Seafloor Spreading Geometry Reorganization. Funding was provided by NSF award OCE11-54071.