The formation of Cratonic keels : seismic EVIDENCE FROM NORTH AMERICA
The age of the subsurface rocks beneath Southeast Canada spans geology from 3/4 of Earth’s history, ranging from the ancient Superior Provence out to the ‘young’ coastal Appalachian terranes. This provides an excellent location to study whether continental scale geological processes have varied greatly over time. To address this issue, the rocks below the surface can be imaged using recorded earthquake waves that travel at speeds controlled by the properties of the rock through which they pass; an imaging technique known as seismic tomography. The more ancient terranes are thought to comprise of a thicker ‘buoyant’ layer of rock known as a keel (highlighted by fast wavespeeds), above the Earth’s mantle, that enables them to remain relatively unchanged since their formation. I aim to use these tomographic images to understand the possible transition from the ancient to modern regime beneath Southeast Canada and whether the continental keel formed over multiple stages.
Having published the most up-to-date relative arrival-time P and S wave tomographic model for SE Canada (Boyce et. al., 2016) I am now working on integrating this dataset (using AARM - see Boyce et al., 2017) into a continent-wide inversion for North America through collaboration with the global Seismology group at MIT.
I am also working on integrating temporary seismograph networks across Africa into the global model of Li et. al., (2008) in collaboration with UROP students and my supervisor Ian Bastow.
See research tab for more details.
I am a member of : Earth and Planets
et al., 2017, From Relative to Absolute Teleseismic Travel Times: The Absolute Arrival-Time Recovery Method (AARM), Bulletin of the Seismological Society of America, Vol:107, ISSN:0037-1106, Pages:2511-2520
et al., 2016, Lithospheric deformation in the Canadian Appalachians: evidence from shear wave splitting, Geophysical Journal International, Vol:206, ISSN:0956-540X, Pages:1273-1280
et al., 2016, Subduction beneath Laurentia modified the eastern North American cratonic edge: Evidence from P wave and S wave tomography, Journal of Geophysical Research-solid Earth, Vol:121, ISSN:2169-9313, Pages:5013-5030
et al., 2016, Peering beneath the Canadian crust, Astronomy & Geophysics, Vol:57, ISSN:1366-8781, Pages:6.24-6.27