|Title||Mass-failure complexes on the central Beaufort Slope, offshore Northwest Territories|
|Licence||Please note the adoption of the Open Government Licence - Canada
supersedes any previous licences.|
|Author||Cameron, G D M;
King, E L|
|Source||Geological Survey of Canada, Open File 8356, 2019, 39 pages, https://doi.org/10.4095/314644 Open Access|
|Publisher||Natural Resources Canada|
|File format||pdf (Adobe® Reader®)|
|Province||Northern offshore region; Northwest Territories|
|NTS||107F/05; 107F/06; 107F/07; 107F/10; 107F/11; 107F/12; 107F/13; 107F/14; 107F/15; 107G/02; 107G/03; 107G/04; 107G/05; 107G/06; 107G/07; 117E/06; 117E/07; 117E/08; 117E/09; 117E/10; 117E/11; 117E/14; 117E/15;
117E/16; 117H/01; 117H/02; 117H/03; 117H/06; 117H/07; 117H/08|
|Lat/Long WENS||-138.5000 -133.5000 71.3333 70.3333|
|Subjects||marine geology; surficial geology/geomorphology; stratigraphy; geophysics; geochronology; continental margins; continental slope; marine sediments; submarine fans; alluvial fans; landslides; landslide
deposits; slope stability; slope failures; mass wasting; scarps; geophysical surveys; acoustic surveys, marine; sonar surveys; side-scan sonar; seismic surveys, marine; seafloor topography; bathymetry; fluid migration; earthquakes; epicentres;
seismic risk; stratigraphic analyses; geological history; depositional history; radiometric dating; carbon-14 dates; submarine canyons; relative ages; Beaufort Slope; Kugmallit Fan; Kugmallit Slide Complex; Ikit Slide Complex; Canada Basin;
Phanerozoic; Cenozoic; Quaternary|
|Illustrations||location maps; geoscientific sketch maps; seismic profiles|
Geoscience Marine Geohazards|
|Program||Program of Energy Research and Development (PERD) |
|Released||2019 04 23|
Interest in oil and gas exploration and development on the Beaufort Slope raises concerns about the potential slope geohazards. Large mass transport slide complexes have been
identified on the Beaufort Slope from multibeam and high-resolution seismic data collected between 2001 and 2010.
Two areas of failed seafloor morphology are identified at mid-slope depths in the Kugmallit Fan Study Area (KF); the Ikit and the
Kugmallit slide complexes. These are mid-size failure complexes, consisting of numerous mass transport deposit (MTD) events, encompassing several failure styles. These are the latest of numerous (older and buried) events and are the focus of this
The Ikit Slide Valley Complex (SVC), found in the western KF, is about 24 km along the shelf break and about 54 km downslope, with an area of 1897 km2. Rotational, retrogress and translational failures are the types of mass transport
mechanisms identified. Some of these include re-failure within the same complex. Crosscutting relationships show that large portions of the failures in the southern Ikit SVC are older than in the northern Ikit SVC and that at least 5 successive
failure events are distinguished.
The Kugmallit Slide Valley Complex, found in the central KF, is about 68 km long and 14 wide, with an area of 1537 km2. Following a large evacuation, rotational and retrogressive failures continued with
crosscutting relationships showing numerous failure entities across at least 6 events. The Ikit and Kugmallit SVCs may be the upper reaches of one larger event.
Migrating fluids likely preconditioned the sediments in the failure areas though
multiple mechanisms are suspected and only broadly known. The widespread occurrence of buried failures indicates a periodic history and suggests that earthquakes were the triggering mechanism in this seismically active area. The occurrence of these
failures, in both SVCs, may have been close in time. Absolute age is likely 1000 years or less from several lines of evidence, but further corroborative study is necessary.
|Summary||(Plain Language Summary, not published)|
Hydrocarbon related activities on the Beaufort Slope raises concerns about geological hazards in the area. Two geologically recent, large, multiple-event
slide valley complexes are identified. Relative timing of as many as five failure events is recognized. The widespread occurrence of failures of varying ages suggests that a number of earthquakes were the triggering mechanism in this seismically
active area. Failure of both glacial and overlying recent sediment suggests these failures are relatively recent.