Understanding the ocean, its creatures and possibilities requires understanding where it ends: the ocean floor. But mapping that remote territory is by no means easy. A team from Nova Scotia Community College recently worked with industry partners to evaluate a new approach to imaging the bottom of the sea.
The partners were evaluating R2Sonic multibeam echosounders, an improved method of sonar backscatter imaging that greatly increases the information returned by sonar surveys of the ocean floor. Types of data that can be derived from a multibeam echosounder survey include water depth, which can be used to show the elevation of the sea floor, its reflectivity, or backscatter, which indicates how hard and rough the bottom is, and water column data including the size and strength of reflectors such as bubbles, fish and plankton in the water.
According to project partner R2Sonic, their new technology allows systems to collect backscatter data at multiple frequencies in a single pass, with one vessel and one sonar system — which results in considerable savings in time and cost.
“The capability to image the seafloor simultaneously with widely separated acoustic frequencies will allow for improved classification and characterization capabilities in addition to a host of other applications that are yet to be discovered,” R2Sonic’s website says.
Leading the evaluation was Dr. Jonathan Beaudoin, chief scientist at QPS evaluation services, who worked with Dr. Craig Brown of Nova Scotia Community College and with Mike Brissette of R2Sonic. The trials were conducted in Halifax’s Bedford Basin in August of 2016. During two sets of field trials, QPS provided software support for acquiring and processing data.
This project will save industries (such as fisheries) considerable cost because it will allow them to map larger areas of the ocean floor using fewer resources, including less vessel time. Industry partners have incorporated this technology into their operations and use the results in their decision making processes. Students were hired as research assistants to work on the project.
