This data set was acquired with a Kongsberg Maritime EM122 Multibeam Sonar during R/V Nathaniel B. Palmer expedition NBP1502 conducted in 2015 (Chief Scientist: Dr. Philip Bart, Investigators: Dr. Philip Bart, Dr. John Anderson). These data files are of MBSystem-compatible format and include Swath Bathymetry data that have not been processed. Data were acquired as part of the project(s): Timing and Duration of the LGM and Post-LGM Grounding Events in Whales Deep Paleo Ice Stream, Eastern Ross Sea Middle Continental Shelf; Evidence for Paleo Ice Stream Collapse in the Western Ross Sea since the Last Glacial Maximum. Funding was provided by NSF award(s): PLR12-46353, PLR12-46357. This data was cited by Bart et al., 2017, Halberstadt et al., 2016, Lee et al., 2017, Simkins et al., 2017.