| Title | Seafloor mapping in a hypertidal setting: Minas Basin, Nova Scotia, Canada |
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| Author | Todd, B J |
| Source | 2022 p. 52 |
| Links | Online - En ligne
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| Image |  |
| Year | 2022 |
| Alt Series | Natural Resources Canada, Contribution Series 20220006 |
| Meeting | 2022 GeoHab Conference; Venice; IT; May 16-20, 2022 |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf |
| Province | Nova Scotia |
| Area | Bay of Fundy; Canada |
| Subjects | Science and Technology; Nature and Environment; marine geology; Minas Basin |
| Illustrations | location maps |
| Program | Marine Geoscience for Marine Spatial Planning |
| Released | 2022 05 16 |
| Abstract | The Bay of Fundy is a large embayment located on the east coast of Canada between the provinces of Nova Scotia and New Brunswick. At the northeastern end of the Bay of Fundy lies the hypertidal Minas
Basin that exhibits the highest recorded tides in the world of 17 m. As a result of the hypertidal nature of the Fundy-Minas system, strong currents are generated, reaching a maximum speed of approximately 5 m/s in Minas Channel at the entrance to
Minas Basin. Over the past century, investigations in this region has been episodic, with peak activity associated with proposals for large infrastructure construction (barriers and turbines) associated with tidal power development by harnessing the
currents. Concern that physical, chemical and ecological changes are taking place in the unique coastal environment Fundy-Minas system has lately generated renewed research. Much of the Minas Basin is less than 20 m deep and its waters are turbid.
The extreme tidal range exposes a large area of intertidal mudflats and salt marshes around the periphery of the basin. The mudflats and marshes host high densities of invertebrates and are a food source for large populations of migrating shorebirds.
This intertidal zone presents a particular surveying challenge to the collection of water depth data. Historically, intertidal zones were not surveyed due to the danger involved in operating surface vessels in coastal areas that dry between tides. To
obtain bathymetric data for this study, the intertidal portion of Minas Basin was mapped during periods of low tide using aircraft-mounted LiDAR (see image below). The mapping revealed the complex topography of the mudflats and the dynamics of sand
bedforms in energetic settings. The nature of the seabed and the subsurface of the Minas Basin is poorly understood; the only known geophysical profiles date to the mid-1960s. The ultimate objective of the research program is to map the entire seabed
of Minas Basin using multibeam sonar either from a surface vessel or from an autonomous underwater vehicle. However, in this hypertidal setting, any vessel/AUV mapping campaign requires an upper bathymetric limit to which to survey. Thus, the first
step in reaching complete seabed coverage was to map to the lowest possible "depth" (i.e. exposed seabed) during periods of low tide. |
| Summary | (Plain Language Summary, not published)
The Bay of Fundy is a large embayment located on the east coast of Canada between the provinces of Nova Scotia and New Brunswick. At the northeastern end
of the Bay of Fundy lies the Minas Basin. To obtain bathymetric data for this study, the intertidal portion of Minas Basin was mapped during periods of low tide using lasers from aircraft. The mapping revealed the complex topography of the mudflats
and the dynamics of sand bedforms in energetic settings. |
| GEOSCAN ID | 329938 |
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