Brian Jeremy Todd

Brian Jeremy Todd
Natural Resources Canada | NRCan · Geological Survey of Canada

Ph.D.

About

225
Publications
52,709
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Introduction
Brian J. Todd is a marine geoscientist at the Geological Survey of Canada at the Bedford Institute of Oceanography in Dartmouth, Nova Scotia, Canada. His work includes mapping the Canadian continental shelf to unravel glacial landsystems, and the paleolimnology and glacial history of the Great Lakes. "A" series maps and Open Files listed here can be downloaded through GEOSCAN: http://geoscan.ess.nrcan.gc.ca/starweb/geoscan/servlet.starweb?path=geoscan/geoscan_e.web
Additional affiliations
January 1997 - present
Bedford Institute of Oceanography
Position
  • Marine Geoscience
June 1990 - January 1996
Natural Resources Canada
Position
  • Engineering Geophysics
Education
May 1984 - April 1988
Dalhousie University
Field of study
  • Marine geoscience
September 1981 - April 1984
Dalhousie University
Field of study
  • Marine geoscience
September 1974 - April 1978
The University of Western Ontario
Field of study
  • Geophysics

Publications

Publications (225)
Technical Report
Full-text available
This study is part of the Marine Geoscience for Marine Spatial Planning (MGMSP) Program which is a Government of Canada initiative focused on improving Impact Assessments and Regulatory Processes (IARP). Natural Resources Canada (NRCan) is one of five departments supporting Environment and Climate Change Canada (ECCC) and Fisheries and Oceans Canad...
Technical Report
Full-text available
This report presents the surficial geology of the Scotian Shelf Bioregion (SSB) (DFO, 2009; Figure 1). The Scotian Shelf surficial geology had been interpreted in the past over the shallower portions of the bioregion (King, 1970; Maclean and King, 1971; Drapeau and King, 1972; Fader et al., 1977; Fader et al., 1978; Fader et al., 1982) as well as o...
Poster
Full-text available
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. The hypertidal nature of the Fundy–Minas system generates strong currents. Propos...
Chapter
Quaternary glaciations played a critical role in producing the modern landscape of the seafloor of southeastern Canada. Glacial landscapes such as cross-shelf troughs, fjords, recessional moraines and tunnel valleys were sculpted by the Laurentide Ice Sheet. Following deglaciation, relative sea level rise led to the formation of sandy bedforms and...
Chapter
The Laurentian Channel is a deep glacial trough located in Atlantic Canada, extending from the St. Lawrence Estuary to the shelf edge between Nova Scotia and Newfoundland. The outer Laurentian Channel close to its entrance at the shelf edge has been designated as an Area of Interest for the establishment of a Marine Protected Area, but baseline inf...
Conference Paper
Full-text available
Extensive seismic-reflection profiling and bathymetric fault mapping in the inland sea of the San Juan Archipelago has enabled the mapping of local earthquake and tsunami hazards in the region. An earthquake could cause rockfalls, which would produce impact tsunamis that could inundate the low-lying coastal areas of islands and the mainland of the...
Article
Full-text available
An overstepped, concave‐eastward, barrier beach beneath Holocene mud in western Lake Ontario has been delineated by acoustic and seismic reflection profiles and piston cores, and related to Early Lake Ontario (ELO). The average ELO barrier depth below present mean lake level is 77.4 to 80.6 m, or about −6 to −2.8 m above present sea level. Trend su...
Article
The Skipjack Island fault zone has been mapped in the San Juan Islands between Vancouver Island, Canada, and the Washington State mainland, USA. A decade ago, interpretation of multibeam sonar seafloor imagery revealed that Skipjack Island, an east–west striking sedimentary bedrock outcrop, was a fault-controlled structural feature. A major fault s...
Presentation
Full-text available
Growing evidence is suggesting that SW subglacial meltwater flooding possibly associated with ice streaming in the glaciated Lake Ontario and eastern Lake Erie basins about 13.5 (16.1 cal) ka BP led to recession of the ice margin in the Mackinaw Interstade about 13.3 ka. This suggestion raises questions whether the earlier Erie Interstade, a retrea...
Technical Report
Full-text available
The seabed of Frobisher Bay exhibits a complex topography reflecting the predominance of exposed bedrock. Superimposed on the bedrock are landforms created by the flow of grounded ice during the last glacial period. As this ice retreated, glaciomarine sediment was deposited in bedrock troughs and was subsequently overlain by postglacial mud. Areas...
Article
Full-text available
The shallow shelf waters of the Beaufort Sea have experienced marine transgression during the Holocene. This has led to a warming of what was terrestrial permafrost by water incursion, and to the dissociation of subsurface gas hydrates which now vent into marine waters. Accompanying this change is the development of conical submarine landforms prod...
Article
Full-text available
Belcher Glacier, a 35 km long tidewater outlet glacier of the 12 000 square kilometre ice cap on Devon Island, is one of the fastest-flowing glaciers in the Canadian Arctic. Belcher Glacier and neighbouring Fitzroy Glacier to the southeast account for about 55% of the iceberg calving loss from the Devon Ice Cap. The terminus of Belcher Glacier rema...
Article
Full-text available
The ~ 200 km-wide Labrador continental shelf consists of a series of shallow banks and intervening cross-shelf troughs (Fig. 1b). Glacial reconstructions suggest that the banks were occupied by slow-flowing ice and the troughs by ice-streams during several Quaternary glaciations (Dyke et al. 2002; Josenhans et al. 1986; Margold et al. 2015). On the...
Article
Full-text available
The configuration of the Bay of Fundy results in large tides (up to 17 m) which give rise to strong currents. Harnessing these currents to generate electricity has been the focus of engineering schemes dating from 1910. Fundy tidal power generation has garnered attention periodically throughout the twentieth century. The seabed and water column con...
Article
Full-text available
The Laurentian Channel is a wide, deep, U-shaped, glacially excavated, cross-shelf trough in Atlantic Canada. It extends NW–SE approximately 700 km from the mouth of the St Lawrence River, across the Gulf of St Lawrence and terminates at the edge of the continental shelf south of Newfoundland. The Laurentian Channel was a major conduit of ice-strea...
Article
Full-text available
The Labrador Shelf and upper continental slope are commonly referred to as ‘Iceberg Alley’, a reference to the 2500–3000 icebergs transported southeastwards past Makkovik Bank every year in the Labrador Current from outlet glaciers in Greenland and eastern Arctic Canada. The larger icebergs are known to contact the seabed from shipbased and satelli...
Article
Full-text available
Glacial landforms and sediments exposed sub-aerially have been the subject of description, analysis and interpretation for more than a century (e.g. De Laski 1864; De Geer 1889). Indeed, such features provided important initial observations informing Louis Agassiz’s ideas that ice was a key instrument in sculpting the landscape and that glaciers an...
Article
Full-text available
M’Clure Strait in the Canadian Beaufort Sea is one of the largest cross-shelf troughs in the High Arctic, with a length of over 1000 km and a maximum cross-trough width of about 250 km. It is thought to be the former location of a fast-flowing ice stream which drained the northwestern Laurentide Ice Sheet during the Late Wisconsinan, and probably a...
Article
Full-text available
The Labrador Shelf is characterized by several cross-shelf troughs separated by intervening shallower banks. The troughs were probably occupied by fast-flowing ice streams in the Late Pleistocene. Hopedale Saddle trough has a long Quaternary history of till progradation at the shelf edge, and the modern continental slope developed over a major 0.3...
Article
Full-text available
The Bay of Fundy–northern Gulf of Maine region surrounds the southern part of Nova Scotia, encompassing, from west to east, the Bay of Fundy, Grand Manan Basin, German Bank, Browns Bank, Northeast Channel and northeastern Georges Bank. During the last glacial maximum (c. 24–20 14C ka BP), the SE margin of the Laurentide Ice Sheet (LIS) occupied the...
Article
Full-text available
Recessional moraines are end moraines deposited during a temporary but significant pause in the final retreat of a glacier or ice sheet. Curvilinear, sub-parallel ridges of sediment on the southern Scotian Shelf are interpreted as recessional moraines formed in proximity to the grounding line of the southeastern extent of the Laurentide Ice Sheet;...
Article
Full-text available
Albatross Bank is a flat glaciated bedrock bank located on the distal edge of the Alaskan continental shelf south of Kodiak Island. The bank illustrates the glacial geomorphology from an active ice edge during Marine Isotopic Stage (MIS) 2 (c. 22–19 ka) sea-level regression. The multibeam echo-sounder (MBES) images presented here provide the first...
Article
Full-text available
Located on the Scotian Shelf, The Gully is the largest submarine canyon on the outer southeastern Canadian continental margin. It indents the continental shelf much deeper than other canyons on the Scotian margin, connecting the middle shelf to the continental slope. It is generally recognized that The Gully formed by fluvial, glacial and meltwater...
Article
Full-text available
Numerous regularly spaced, parallel, linear to curvilinear ridges of sediment are recognized to form at or close to the grounding lines of water-terminating glaciers. These iceflow transverse ridges, sometimes known as De Geer moraines (De Geer 1889), have modest heights and widths and variable lengths. De Geer’s original description of Swedish mor...
Article
Full-text available
Ice-proximal fans are found where subglacial streams reach the margins of grounded tidewater glaciers. As the streams enter the marine environment, they lose energy and deposit their sedimentary load. The primary factors influencing the development of ice-proximal fans in a submarine setting are sediment supply and the stability of the parent glaci...
Article
Full-text available
The original version of this glossary was published almost 20 years ago in the landmark volume Glaciated Continental Margins: An Atlas of Acoustic Images (Bell et al. 1997). For the present volume, we have modified the text and added academically accepted terminology gleaned from the manuscripts submitted to the present Atlas of Submarine Glacial L...
Article
Full-text available
Elongate glacial landforms are typically orientated in the direction of ice flow. They are often preserved in the submarine environment, providing information on past ice-sheet extent and flow pathways. The northeastern margin of the Laurentide Ice Sheet (LIS) covered much of eastern Baffin and Bylot islands during the Last Glacial Maximum. Numerou...
Article
Full-text available
Glacimarine processes affect about 20%of the global ocean today, and this area expanded considerably under cyclical full-glacial conditions during the Quaternary. Many of the submarine landforms produced at the base and margin of past ice sheets remain well preserved on the seafloor in fjords and on high-latitude continental shelves after the retre...
Article
Full-text available
Glaciers erode bedrock at all scales, from striations of millimetres in width through to the landscape-scale of U-shaped valleys and fjords. Glacier erosion processes include fine-scale abrasion and the fracture of larger rock fragments. These processes take place especially where high stress concentrations are present below rock particles held at...
Article
Full-text available
This part of the Atlas of Submarine Glacial Landforms provides brief descriptions of the most commonly applied acoustic mapping methods used elsewhere in this book, their capabilities, limitations and typical errors. It begins with an introduction to how the use of acoustic geophysical survey methods has evolved within the field of marine glacial l...
Article
Full-text available
In areas where bedrock outcrops are situated between converging glaciers, longitudinal debris accumulations mark the boundary between adjacent ice-flow units. These medial moraines often give the glacier surface a striped appearance. The seafloor offshore from Scott Inlet, Arctic Canada, exhibits well-preserved medial moraines and other elongate fe...
Conference Paper
Frobisher Bay, a macrotidal inlet of the Labrador Sea in southeastern Baffin Island, is 230 km long and varies in width from 40 km at its southeastern extremity to 20 km at its northwest end. It lies within the territory of Nunavut, which has the land area equivalent to Western Europe, but with a population of only ~30,000. Competing industrial use...
Conference Paper
The Skipjack Island Fault Zone has been mapped in the San Juan Islands between Vancouver Island, Canada, and the Washington State mainland, USA. A decade ago, interpretation of multibeam sonar seafloor imagery revealed that Skipjack Island, an east–west striking sedimentary bedrock outcrop, was a fault-controlled structural feature. A major fault s...
Conference Paper
The Heinrich 1 event (H1) about 14–13 ka (~17-15 cal ka) which discharged icebergs throughout the North Atlantic Ocean led to instability in, and reorganization of, the Laurentide Ice Sheet (LIS). Sediments deposited subglacially between 14.4 and 13.6 ka in the Finger Lakes area of New York State (NYS) by southward flowing meltwater from a modelled...
Article
This is the author accepted manuscript. It is currently under an indefinite embargo pending publication by The Geological Society.
Technical Report
Full-text available
Georges Bank is a shallow submarine bank that lies south of Nova Scotia and east of Cape Cod, Massachusetts. It bounds the seaward side of the Gulf of Maine and rises more than 300 m above the Gulf of Maine seafloor. The bank is approximately 280 km long and 150 km wide and has an area of 42,000 square kilometres in water depths less than 200 m (Ca...
Conference Paper
Lakebed relief in deep water of eastern Lake Ontario, portrayed in conventional hydrographic charts, is dominated by long linear WSW-trending ridges. The ridges had been interpreted in the early 1990s variously as Holocene fault scarps, and as streamline glacial landforms. A multibeam survey confirmed the trend of lakefloor relief, but showed that...
Technical Report
Full-text available
1.1 Objectives of the Guide Marine renewable energy (tide, wave and offshore wind) is available in large quantities for integration into the Canadian energy mix (Cornett, 2006), but the ocean is a harsh and unforgiving environment that presents major engineering challenges to industry. The development of standards and best practices for site and su...
Conference Paper
M’Clure Strait in the Canadian Beaufort Sea is one of the largest cross-shelf troughs in the High Arctic, with a length of over 1000 km and a maximum cross-trough width of around 250 km. M’Clure Strait has been suggested to be the former location of a fast-flowing ice stream which drained the northwestern margin of the Laurentide Ice Sheet during t...
Conference Paper
Full-text available
Glacial landforms are generated from the activity of glaciers and display spatial dimensions ranging from below one meter up to tens of kilometers. Glacial landforms are used as diagnostic features of past activity of ice sheets and glaciers; they are specifically important in the field of palaeoglaciology. Mapping of submarine glacial landforms is...
Chapter
Full-text available
The wide continental shelves of Atlantic Canada are characterized by a series of banks separated by transverse troughs. These shelves have been imprinted by repeated Quaternary glaciations, so that fluvial valleys have been deepened into fjords and shelf-crossing troughs, and a suite of glacigenic sediments has been deposited. In shallow areas the...
Chapter
Full-text available
For many years researchers have been aware of the association between benthic and pelagic communities and their physical habitats. However, not until the 1990s when multibeam mapping became commonplace, was it possible to ‘strip away the water column’ to provide high-resolution imagery of the seabed and to accurately map the physical environment. F...
Chapter
Full-text available
Studies of the Great Lakes and Lake Winnipeg were undertaken during the 1990 and 2000 decades using the methods of marine and coastal geoscience. Expeditions were commonly conducted with collaborators to address societal concerns. Lake Ontario sediments and bedrock were surveyed for evidence of recent deformation and earthquake shaking, natural pro...
Chapter
Full-text available
Mapping of the Bay of Fundy by Europeans commenced in the 1600s and systematic geological mapping began in the 1960s, culminating with a published map in 1977. In partnership with the Canadian Hydrographic Service and the University of New Brunswick, the Geological Survey of Canada began a new round of systematic mapping of the Bay of Fundy with mu...
Article
Full-text available
Multibeam sonar mapping and geophysical and geological groundtruth surveys were coupled with tidal current and sediment transport model calculations to investigate the sediment transport and formation processes of the complex seabed features off the Cape Split headland in the upper Bay of Fundy. The Cape Split banner bank, composed of coarse to ver...
Article
The macrotidal Bay of Fundy, Canada, was systematically mapped in the early 2000 s using multibeam sonar technology, partly to support efforts to develop hydropower. The primary product was a suite of 1:50,000-scale maps of shaded seafloor relief and backscatter. In addition, a ‘seascape’ map was produced in an attempt to classify the entire bay in...
Article
The Bay of Fundy, Canada, a large macrotidal embayment with the World's highest recorded tides, was mapped using multibeam sonar systems. High-resolution imagery of seafloor terrain and backscatter strength, combined with geophysical and sampling data, reveal for the first time the morphology, architecture, and spatial relationships of a spectrum o...
Data
Full-text available
Georges Bank is a large submarine bank in the Gulf of Maine near the edge of the continental shelf south of Nova Scotia and east of Cape Cod. The bank is approximately 280 km long and 150 km wide. The international boundary between Canada and the United States transects the bank with the northeastern third of the bank being Canadian territory. Thi...
Data
Georges Bank is a large submarine bank in the Gulf of Maine near the edge of the continental shelf south of Nova Scotia and east of Cape Cod. The bank is approximately 280 km long and 150 km wide. The international boundary between Canada and the United States transects the bank with the northeastern third of the bank being Canadian territory. Thi...
Data
Full-text available
Georges Bank is a large submarine bank in the Gulf of Maine near the edge of the continental shelf south of Nova Scotia and east of Cape Cod. The bank is approximately 280 km long and 150 km wide. The international boundary between Canada and the United States transects the bank with the northeastern third of the bank being Canadian territory. Thi...
Data
Full-text available
Georges Bank is a large submarine bank in the Gulf of Maine near the edge of the continental shelf south of Nova Scotia and east of Cape Cod. The bank is approximately 280 km long and 150 km wide. The international boundary between Canada and the United States transects the bank with the northeastern third of the bank being Canadian territory. Thi...
Data
Full-text available
Georges Bank is a large submarine bank in the Gulf of Maine near the edge of the continental shelf south of Nova Scotia and east of Cape Cod. The bank is approximately 280 km long and 150 km wide. The international boundary between Canada and the United States transects the bank with the northeastern third of the bank being Canadian territory. Thi...
Data
Georges Bank is a large submarine bank in the Gulf of Maine near the edge of the continental shelf south of Nova Scotia and east of Cape Cod. The bank is approximately 280 km long and 150 km wide. The international boundary between Canada and the United States transects the bank with the northeastern third of the bank being Canadian territory. Thi...
Data
Full-text available
Georges Bank is a large submarine bank in the Gulf of Maine near the edge of the continental shelf south of Nova Scotia and east of Cape Cod. The bank is approximately 280 km long and 150 km wide. The international boundary between Canada and the United States transects the bank with the northeastern third of the bank being Canadian territory. Thi...
Data
Full-text available
Georges Bank is a large submarine bank in the Gulf of Maine near the edge of the continental shelf south of Nova Scotia and east of Cape Cod. The bank is approximately 280 km long and 150 km wide. The international boundary between Canada and the United States transects the bank with the northeastern third of the bank being Canadian territory. Thi...
Data
Full-text available
Georges Bank is a large submarine bank in the Gulf of Maine near the edge of the continental shelf south of Nova Scotia and east of Cape Cod. The bank is approximately 280 km long and 150 km wide. The international boundary between Canada and the United States transects the bank with the northeastern third of the bank being Canadian territory. Thi...
Data
Full-text available
Georges Bank is a large submarine bank in the Gulf of Maine near the edge of the continental shelf south of Nova Scotia and east of Cape Cod. The bank is approximately 280 km long and 150 km wide. The international boundary between Canada and the United States transects the bank with the northeastern third of the bank being Canadian territory. This...
Article
Since sea level stabilized 7000 yr BP, shelf seas experiencing semi-diurnal tides will have been affected by streaming four times per day. If tidal erosion of bedrock were even only marginally efficient, the ~10 million streamings since then should have left geomorphological imprints. We examine high-resolution multibeam sonar data from three areas...
Article
Full-text available
The successful design of robust marine tidal power facilities must surmount the many challenges associated with corrosion by seawater, and impacts of waves and tidal currents. Whereas useful indications of facility material survival may be obtained from laboratory testing, geological studies of potential seabed placement sites can provide useful in...
Article
In the past two decades there have been several advances that make the production of an atlas of submarine glacial landforms timely. First is the development of high-resolution imaging technologies; multi-beam echo-sounding or swath bathymetry that allows the detailed mapping of the sea floor at water depths of tens to thousands of metres across co...
Conference Paper
A massive, overstepped, sand and gravel barrier beach beneath Holocene mud in western Lake Ontario has been delineated in piston cores, and acoustic and seismic reflection profiles between the communities of Grimsby and Oakville, Ontario. The Grimsby-Oakville barrier crest is about 78 to 80 m below the lake and 3 to 5 m below present sea level. A s...
Data
Shaded seafloor Georges Bank is a shallow submarine bank that lies south of Nova Scotia and east of Cape Cod, Massachusetts and bounds the seaward side of the Gulf of Maine. Water depths on the bank range from less than 5 m to 200 m. The bank is approximately 280 km long and 150 km wide, and has an area of 42,000 square kilometres in water depths l...
Data
Shaded seafloor Georges Bank is a shallow submarine bank that lies south of Nova Scotia and east of Cape Cod, Massachusetts and bounds the seaward side of the Gulf of Maine. Water depths on the bank range from less than 5 m to 200 m. The bank is approximately 280 km long and 150 km wide, and has an area of 42,000 square kilometres in water depths l...