Earthquakes can range in size from those that are too weak to be felt to those violent enough to wreak destruction across entire cities. The seismic activity of an area is the frequency, type, and size of earthquakes experienced over a period of time. Can we possibly predict earthquakes just like we can predict hurricanes, floods, and tornados to varying extents? Our understanding of what causes earthquakes is based on the idea that the earth’s outer crust is composed of movable slabs of rock called tectonic plates. These plates can shift and move on top of the rocky, yet mostly malleable medium below them, called the mantle, which sits above the molten material of the Earth’s core.
The geology of Northwestern Canada presents an interesting mix of a thin and hot mountainous crust and thick and cold stable crust, which has important implications for regional geodynamics. Increased seismic station coverage across northwestern Canada has been crucial for the development of three-dimensional models of the crust and mantle (0-300 km depth) at high resolution using seismic imaging techniques to gain insight into the tectonic evolution and geodynamics of the region. Fascinated by these imaging techniques and analytical tools, PhD graduate Clément Estève used them to study investigate hidden features the Canadian mantle such as the Tintina Fault, Laurentian craton and Mackenzie craton.
Clément’s current research focuses on the enigmatic seismic activity in the Beaufort Sea (western Canadian Arctic). The largest earthquake (Ms 6.5) in the Beaufort Sea occurred in 1920, suggesting that the region is subject to infrequent but large earthquakes. With the recent deployment of seismic networks such as the Banks Island Seismic Network across Northwest Territories, new seismic data are available from several stations in close proximity to the Beaufort Sea. The availability of new seismic data combined with increased access to cost-effective computation resources has led to insights about the mysterious subsurface geology of Northwestern Canada. During his PhD, Clément was personally involved in the maintenance of these seismic stations and the installation of a new station on the Beaufort Sea margin (in Tuktoyaktuk, NWT).
A recent graduate from uOttawa, Clément worked under the guidance of Professor Pascal Audet. He received the Jack Henderson Prize awarded for the Best PhD Thesis from the Canadian Tectonics Group (a Division of the Geological Association of Canada). Clément is now a Wares Postdoctoral Fellow at McGill University.
Read more:
- Surface-Wave Tomography of the Northern Canadian Cordillera Using Earthquake Rayleigh Wave Group Velocities
- Seismic evidence for craton chiseling and displacement of lithospheric mantle by the Tintina Fault in the Northern Canadian Cordillera
- The upper mantle structure of northwestern Canada from teleseismic body wave tomography
- Upper mantle structure underlying the diamondiferous Slave craton from teleseismic body-wave tomography
