| Title | Multiscale geomorphological classification of the seafloor in an active continental volcanic setting - Bay of Plenty, New Zealand |
| Download | Download (whole publication) |
| |
| Licence | Please note the adoption of the Open Government Licence - Canada
supersedes any previous licences. |
| Author | Lamarche, G; Guntz, M; Mackay, K; Pallentin, A; Rowden, A |
| Source | Program and abstracts: 2017 GeoHab Conference, Dartmouth, Nova Scotia, Canada; by Todd, B J ; Brown, C J; Lacharité, M; Gazzola, V; McCormack, E; Geological Survey of Canada, Open File 8295, 2017 p. 74, https://doi.org/10.4095/305882  Open Access |
| Links | GeoHab 2017
|
| Year | 2017 |
| Publisher | Natural Resources Canada |
| Meeting | 2017 GeoHab: Marine Geological and Biological Habitat Mapping; Dartmouth, NS; CA; May 1-4, 2017 |
| Document | open file |
| Lang. | English |
| Media | on-line; digital |
| Related | This publication is contained in Program and abstracts: 2017
GeoHab Conference, Dartmouth, Nova Scotia, Canada |
| File format | pdf |
| Area | Bay of Plenty; New Zealand |
| Lat/Long WENS | 175.5000 178.5000 -37.5000 -38.0000 |
| Subjects | marine geology; surficial geology/geomorphology; environmental geology; geophysics; mapping techniques; oceanography; marine environments; coastal studies; conservation; marine organisms; marine
ecology; resource management; biological communities; environmental studies; ecosystems; benthos; bathymetry; seafloor topography; bedforms; geophysical surveys; acoustic surveys, marine; sonar surveys; side-scan sonar; photography; modelling;
submarine features; seismicity; bedrock geology; structural features; faults; volcanism; submarine hydrothermal vents; Calypso vent fields; Biology; geographic information system applications |
| Program | Offshore Geoscience |
| Released | 2017 09 26 |
| Abstract | Detailed knowledge of the physical and biological conditions of the seafloor is key to the development of economic, environmental and cultural activities in the marine environment. Full coverage
information on substrate and benthic habitat relies almost exclusively on acoustic remote-sensed data provided by multibeam echosounders, subsequently ground-truthed using visual observations and physical sampling. Predictive habitat mapping provides
a means to develop models of seafloor habitat in regions where only acoustic data are available.
The diverse geomorphology and benthic ecology in the Bay of Plenty makes the area a useful case study for developing regional and local models of
benthic habitat: water depths range 0 - 3300 m with geomorphological features including channel, canyons, seamounts and ridges at a variety of scales. Active geology is demonstrated by the intense seismicity, dense fault network, and ubiquitous
submarine volcanic activity that results in venting hydrothermal fluids at, for example, the Calypso vent fields. This environment provides habitat for benthic communities, whose structure and distribution can be expressed at a variety of scales.
Multiscale seafloor topography classification is strongly dependent on the quality of the bathymetric data. In this study we combined multibeam echosounder (MBES) data from a variety of systems, data collected on transit, and dedicated scientific
and hydrographic surveys, with data from the New Zealand national bathymetry model derived from historic and modern single-beam echosounder (SBES) data for areas without MBES coverage.
We integrated marine geological and oceanographic information
in Benthic Terrain Models of the Bay of Plenty and the Calypso vent fields, i.e. at regional and local scales using the ESRI ArcGIS Benthic Terrain Modeler (BTM) tools, with a modified classification catalog to suit the highly variable terrain of the
Bay of Plenty. Classification of the geomorphology was based on a number of morphometric parameters (e.g., slope, Bathymetric Positioning Index, curvature, rugosity) derived from the bathymetry gridded at 25 m for the region, and 5 m for the Calypso
vent fields.
A 13 geomorphological class catalogue was used that differentiated large (broad slopes, basins) and local (knolls, narrow ridges/valleys) scale features. Seventy-seven percent of the 25,000 km2 study area is broad flat, the remainder
is dominated by local ridges and narrow depressions. Ground-truthing data will enable us to associate biological observations to each class, and predict benthic habitat in region where no observations exist. |
| Summary | (Plain Language Summary, not published)
The sixteenth annual GeoHab Conference was held this year (2017) at the Waterfront Campus of the Nova Scotia Community College in Dartmouth, Nova Scotia,
Canada. |
| GEOSCAN ID | 305882 |
|
|