Abstract: Systems and methods for surveying a seafloor utilize two or more of seismic data, acoustic data and electrical potential or resistivity data to identify the locations of objects on or beneath the seafloor. The methods involve moving survey equipment over a geographic area of the seafloor and conducting a plurality of sensing or detecting operations while moving the survey equipment over the geographic area. The plurality of operations include two or more of: (1) a seismic operation that emits seismic energy toward the seafloor and collects seismic data based on seismic energy that returns from the seafloor, (2) an acoustic operation that emits acoustic energy toward the seafloor and collects acoustic data based on acoustic energy that returns from the seafloor, and/or (3) an electrical operation that supplies electrical power into seawater and that collects electric potential data indicative of electric potential that is induced into the seawater.