As a part of reconnaissance sub-bottom acoustic profiling (SAP) survey on Lac Opasatica, Quebec, 19 SAP were collected from the northern bay area and 27 SAP were collected within Baie Lamy on July 15 and 18, 2014, respectively. Good penetration of the sub-bottom was obtained in most of the two profiled areas. Three facies can be identified within the SAP returns that represent lacustrine, glaciolacustrine and mass movement deposits. The profiles collected from Lac Opasatica demonstrate the widespread presence of mass movement deposits within this basin. Baie Lamy is the better location for any follow-up detailed profiling and core collection because of water depths that are generally shallower than the northern bay.