Fieldwork in the Scotian Shelf

Caroline Gini

In November 2021, I was able to travel to Nova Scotia to conduct fieldwork to collect essential data for my research. I am investigating the benefits and challenges of using an acoustic mapping and imaging technology, the interferometric synthetic aperture sonar (InSAS), for geological mapping of the seafloor. The imagery and bathymetry of the seafloor acquired using InSAS is at a much higher resolution (centimeter) than what commonly used technologies can provide (meter resolutions).

Sunrise on the Scotian Shelf, in transit to the survey site.

To produce a valid geological map of the seafloor, we need video imagery to support the identification of different lithological classes on the acoustic imagery. With some colleagues from the Dalhousie University, we deployed an underwater camera from the MV Eastcom, a diving vessel, on selected sites of interest offshore Halifax, on the Scotian Shelf. We departed from Halifax at 6:30 am, after installing and securing the equipment on the boat, and steamed for 2 hours to reach the survey site. Once on-site, we manually dropped the camera overboard down to the seafloor and recorded video footage using a controller with a live feed.

Deep Trekker Pod setup on the back deck of the MV Eastcom, in transit back to Halifax.

After 3 days of survey, we collected video footage at 42 sites on the seafloor! We were very lucky with the weather since the North Atlantic in November can be unpleasant.

Back in the office, I will review the video footage to report changes in the geology of the seafloor for future comparison with the InSAS imagery, and finally produce the first geological map using InSAS.

The fieldwork was conducted with the help from Esther Bushuev, Poppy Keogh, Larissa Pattison, Jake Tan, the captain and crew of the MV Eastcom. This project is supported by Mitacs Accelerate Fellowship, Ocean Frontier Institute, Kraken Robotic Systems Inc. and is co-supervised by Dr. Katleen Robert at MI and Dr. John Jamieson at MUN.

Left to right, Poppy and Caroline monitoring the camera on the seafloor from the controller, and Esther operating the camera depth with the cable.