Sismologie, risques
Structure de la croûte et ressources minérale
darbyshire.fiona_ann [at] uqam.ca (darbyshire[dot]fiona_ann[at]uqam[dot]ca)
Mots-clés: seismology, tectonophysics, subcontinental lithosphere, broadband seismographs, teleseismic data, surface waves, anisotropy, Canadian Shield
The Canadian Shield and its margins preserve over 3 billion years of Earth’s geological history, making it an ideal natural laboratory to study the processes of formation and evolution of the continental crust and mantle lithosphere, and their interactions with the underlying mantle. In my research, I study the present-day seismic structure of the crust and upper mantle, using global earthquakes recorded at networks of broadband seismograph stations. I use the resulting models to investigate fundamental questions such as the assembly of the North American continent, and the history of Precambrian and later plate-tectonic processes.
My research group employs a wide variety of techniques to exploit the seismic waveforms, including P-wave receiver functions, ambient noise and surface-wave tomography, relative and absolute travel-time tomography, and shear wave splitting. These techniques allow us to model the seismic velocity structure of the crust and upper mantle, as well as to measure seismic anisotropy, which highlights structural alignments and/or convective mantle flow. In addition, we have recently collaborated with colleagues in Australia to carry out joint inversions of seismic, geodynamic and geochemical data to explore the thermochemical structure of the Canadian Shield lithosphere, which has implications for mineral resource prospectivity.
I am responsible for a network of 17 long-term broadband seismograph stations installed across Québec and Labrador, and have also participated in a number of temporary installations related to the North American EarthScope project. These installations have illuminated the structures beneath important tectonic domains such as the billion-year-old Mid-Continent Rift, and the systematic variations in lithospheric properties from the Archean to the Phanerozoic. I am also a collaborator on a CFI-funded project to develop a new Canadian pool of ocean-bottom seismometers which will allow further extension of the structural studies offshore.
Darbyshire, F.A., Bastow, I.D., Petrescu, L., Gilligan, A., Thompson, D.A., 2017. A tale of two orogens: Crustal processes in the Proterozoic Trans-Hudson and Grenville Orogens, eastern Canada. Tectonics 36 (8), 1633-1659.
Levin, V., Servali, A., Van Tongeren, J., Menke, W., Darbyshire, F., 2017. Crust-mantle boundary in eastern North America, from the (oldest) craton to the (youngest) rift. Special Paper of the Geological Society of America 526, 107-131.
Liddell, M.V., Bastow, I., Darbyshire, F., Gilligan, A. and Pugh, S., 2017. The formation of Laurentia: Evidence from shear wave splitting. Earth and Planetary Science Letters 479, 170-178.
Petrescu, L., Darbyshire, F., Bastow, I., Totten, E., Gilligan, A., 2017. Seismic anisotropy of Precambrian lithosphere: Insights from Rayleigh wave tomography of the eastern Superior Craton. Journal of Geophysical Research: Solid Earth 122 (5), 3754-3775.
Boyce, A., Bastow, I.D., Darbyshire, F.A., Ellwood, A.G., Gilligan, A., Levin, V., Menke, W., 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 121 (7), 5013-5030.
Gilligan, A., Bastow, I.D., Darbyshire, F.A., 2016. Seismological structure of the 1.8 Ga Trans-Hudson Orogen of North America. Geochemistry, Geophysics, Geosystems 17, 2421-2433.
Gilligan, A., Bastow, I.D., Watson, E., Darbyshire, F.A., Levin, V., Menke, W., Lane, V., Hawthorn, D., Boyce, A., Liddell, M.V., Petrescu, L., 2016. Lithospheric deformation in the Canadian appalachians: Evidence from shear wave splitting. Geophysical Journal International 206 (2), 1273-1280.
Menke, W., Skryzalin, P., Levin, V., Harper, T., Darbyshire, F., Dong, T., 2016. The Northern Appalachian Anomaly: A modern asthenospheric upwelling. Geophysical Research Letters 43 (19), 10,173-10,179.
Petrescu, L., Bastow, I.D., Darbyshire, F.A., Gilligan, A., Bodin, T., Menke, W., Levin, V., 2016. Three billion years of crustal evolution in eastern Canada: Constraints from receiver functions. Journal of Geophysical Research B: Solid Earth 121 (2), 788-811.
Zhang, H., van der Lee, S., Wolin, E., Bollmann, T.A., Revenaugh, J., Wiens, D.A., Frederiksen, A.W., Darbyshire, F.A., Aleqabi, G.I., Wysession, M.E., Stein, S., Jurdy, D.M., 2016. Distinct crustal structure of the North American Midcontinent Rift from P wave receiver functions. Journal of Geophysical Research: Solid Earth 121 (11), 8136-8153.
Bastow, I.D., Eaton, D.W., Kendall, J.-M., Helffrich, G., Snyder, D.B., Thompson, D.A., Wookey, J., Darbyshire, F.A., Pawlak, A.E., 2015. The Hudson Bay Lithospheric Experiment (HuBLE): Insights into Precambrian plate tectonics and the development of mantle keels. Geological Society Special Publication 389 (1), 41-67.
Darbyshire, F. A., Bastow, I. D., Forte, A. M., Hobbs, T. E., Calvel, A., Gonzalez‐Monteza, A., & Schow, 2015. Variability and origin of seismic anisotropy across eastern Canada: evidence from shear‐wave splitting measurements. Journal of Geophysical Research: Solid Earth.
Porritt, R.W., Miller, M.S., Darbyshire, F.A., 2015. Lithospheric architecture beneath Hudson Bay. Geochemistry, Geophysics, Geosystems 16 (7), 2262-2275.
Wolin, E., van der Lee, S., Bollmann, T.A., Wiens, D.A., Revenaugh, J., Darbyshire, F.A., Frederiksen, A.W., Stein, S., Wysession, M.E., 2015. Seasonal and diurnal variations in long-period noise at SPREE stations: The influence of soil characteristics on shallow stations’ performance. Bulletin of the Seismological Society of America 105 (5), 2433-2452.
Darbyshire, F.A., Eaton, D.W., Bastow, I.D. 2013, Seismic imaging of the lithosphere beneath Hudson Bay: Episodic growth of the Laurentian mantle keel, Earth and Planetary Science Letters, vol. 373, pp. 179-193.
Frederiksen, A.W., Bollmann, T., Darbyshire, F., Van Der Lee, S. 2013, Modification of continental lithosphere by tectonic processes: A tomographic image of central North America, Journal of Geophysical Research, vol. 118, no. 3, pp. 1051-1066.
Villemaire, M., Darbyshire, F.A., Bastow, I.D. 2012. P-wave tomography of eastern North America: Evidence for mantle evolution from Archean to Phanerozoic, and modification during subsequent hot spot tectonism, Journal of Geophysical Research : Solid Earth, 117 (12).
Villemaire, M., Darbyshire, F.A., Bastow, I.D., 2012. Evolution of the mantle from Archean to Phanerozoic and its modification during subsequent hotspot tectonism : seismic evidence from eastern North America. Journal of Geophysical Research, 117, doi:10.1029/2012JB009639
Pawlak, A., Eaton, D.W., Darbyshire, F., Lebedev, S., Bastow, I.D. 2012. Crustal anisotropy beneath Hudson Bay from ambient noise tomography: Evidence for post-orogenic lower-crustal flow? Journal of Geophysical Research B: Solid Earth, 117.
Bastow, I.D., Thompson, D., Wookey, J., Kendall, J.-M., Helffrich, G., Snyder, D., Eaton, D. & Darbyshire, F.A.,2011. Precambrian plate tectonics: Seismic evidence from Hudson Bay, Canada, Geology, 39, 91-94.
Stein, S., van der Lee, S., Jurdy, D., Stein, C., Wiens, D., Wysession, M., Revenaugh, J., Frederiksen, A., Darbyshire, F., Bollman, T., Lodewyk, J., Wollin, E., Merino, M. & Tekverk, K., 2011. Learning from failure: the SPREE Mid-Continent Rift Experiment, GSA Today, 21(9), 5-7.
Darbyshire, F.A., Eaton, D.W., 2010. The lithospheric root beneath Hudson Bay, Canada from Rayleigh-wave dispersion: No clear seismological distinction between Archean and Proterozoic mantle, Lithos, 120(1-2), 144-159.
Eaton, D.W., Darbyshire, F., 2010. Lithospheric architecture and tectonic evolution of the Hudson Bay region, Tectonophysics, 480(1-4), 1-22.
Darbyshire, F. A., Lebedev, S., 2009. Rayleigh wave phase-velocity heterogeneity and multi-layered azimuthal anisotropy of the Superior Craton, Ontario, Geophysical Journal International, 176 (1), 215-234. GEOTOP publication n° 2008-0028.
Eaton, D.W., Darbyshire, F., Evans, R., Grutter, H., Jones, A., Yuan, X., 2009. The elusive lithosphere-asthenosphere boundary beneath cratons, Lithos special issue, 109 (1-2), 1-22.
Darbyshire, F.A., Eaton, D.W., Frederiksen, A.W., Ertolahti, L., 2007. New insights into the lithosphere beneath the Superior Province from Rayleigh wave dispersion and receiver function analysis, Geophys. J. Int., 169(3), 1043-1068, doi:10.1111/j.1365-246X.2006.03259.x.
Frederiksen, A.W., Miong, S.-K., Darbyshire, F., Eaton, D., Rondenay, S., Sol, S., 2007. Variations in Lithospheric Thickness Across the Superior Province, Ontario, Canada: Evidence from Tomography and Shear-Wave Splitting, J. Geophys. Res., 112, doi:10.1029/2006JB004861.
Darbyshire, F.A., Asudeh, I., 2006. Generic instrument responses for the POLARIS and FedNor seismograph network in Canada, Geol. Surv. Canada, Open File 5185, 23pp.
Darbyshire, F.A., 2005. Upper mantle structure of Arctic Canada from Rayleigh wave dispersion,Tectonophysics, 405, 1-23.
Darbyshire, F.A., Larsen, T.B., Mosegaard, K., Dahl-Jensen, T., Gudmundsson, Ó., Bach, T., Gregersen, S., Pedersen, H.A., Hanka, W., 2004. A first detailed look at the Greenland lithosphere and upper mantle, using Rayleigh wave tomography, Geophys. J. Int., 158, 267-286.
Darbyshire, F.A., 2003. Crustal structure across the Canadian High Arctic region from teleseismic receiver function analysis, Geophys. J. Int., 152, 372-391.
Snyder, D., Asudeh, I., Darbyshire, F., Drysdale, J., 2002. Field-based feasibility study of teleseismic surveys at high northern latitudes, Northwest Territories and Nunavut, Geol. Surv. Canada, Current Research C03, 10 pp.
Weir, N.R.W., White, R.S., Brandsdóttir, B., Einarsson, P., Shimamura, H., Shiobara, H., RISE fieldwork team,2001. Crustal structure of the northern Reykjanes Ridge and Reykjanes Peninsula, southwest Iceland, J. Geophys. Res.,106, 6347-6368.
Darbyshire, F.A., White, R.S., Priestley, K.F., 2000. Structure of the crust and uppermost mantle of Iceland from a combined seismic and gravity study, Earth Planet. Sci. Lett.,181, 409-428.
Darbyshire, F.A., Priestley, K.F., White, R.S., Stefánsson, R., Jakobsdóttir, S., Gudmundsson, G.,2000. Crustal structure of central and northern Iceland from analysis of teleseismic receiver functions, Geophys. J. Int., 143, 163-184.
Département des sciences de la Terre et de l'atmosphère, Université du Québec à Montréal
Codirection : Nasser Kazemi, Département des sciences de la Terre et de l'atmorspère, UQAM
Sujet de recherche : Amélioration d’algorithmes pour l’imagerie sismique haute-résolution de la sous-surface