Geophysical bathymetry survey is a technique used to measure and map the depth and shape of the seafloor or lakebed using geophysical methods. Here are some of the most common techniques used in geophysical bathymetry surveys:
Multibeam sonar: Multibeam sonar is a technique that uses sound waves to measure the depth and shape of the seafloor or lakebed. By sending out multiple beams of sound waves and measuring the time it takes for the waves to bounce back, multibeam sonar can create a detailed three-dimensional map of the seafloor or lakebed.
Single-beam sonar: Single-beam sonar is a technique that uses a single beam of sound waves to measure the depth of the seafloor or lakebed. By measuring the time it takes for the sound waves to bounce back, single-beam sonar can create a two-dimensional map of the seafloor or lakebed.
Side-scan sonar: Side-scan sonar is a technique that uses sound waves to create images of the seafloor or lakebed. By sending out sound waves and measuring the echoes that bounce back, side-scan sonar can create images of the seafloor or lakebed that show the topography and texture of the surface.
Seismic reflection: Seismic reflection is one of the geophysical technique that is not commonly used in near surface surveys for this application. The method uses sound waves to measure the depth and structure of the seafloor or lakebed (water bodies). By sending out sound waves and measuring the reflections that bounce back from different layers of sediment and rock, seismic reflection can create a detailed image of the subsurface geology.
Gravity measurements: Gravity measurements are a technique that uses gravity to measure the depth of the seafloor or lakebed. By measuring the slight variations in the Earth's gravity caused by the presence of underwater mountains and valleys, gravity measurements can create a map of the seafloor or lakebed.
Geophysical bathymetry surveys are important for many applications, including marine navigation, offshore resource exploration, and environmental monitoring. The choice of technique depends on the specific requirements of the survey and the characteristics of the seafloor or lakebed being studied.