HR: 1340h
AN: T23A-1200    [Abstracts]
TI: The Manitoba Teleseismic Array: Examining the Westward Extent of the Superior Craton in Canada
AU: * Frederiksen, A W
EM: frederik@cc.umanitoba.ca
AF: University of Manitoba, Department of Geological Sciences University of Manitoba 125 Dysart Road, Winnipeg, MB R3T 2N2, Canada
AU: McCutcheon, J
EM: jmccutcheon7@shaw.ca
AF: University of Manitoba, Department of Geological Sciences University of Manitoba 125 Dysart Road, Winnipeg, MB R3T 2N2, Canada
AU: Unrau, T
EM: troy.unrau@gmail.com
AF: University of Manitoba, Department of Geological Sciences University of Manitoba 125 Dysart Road, Winnipeg, MB R3T 2N2, Canada
AU: Idowu, O
EM: umidowu2@cc.umanitoba.ca
AF: University of Manitoba, Department of Geological Sciences University of Manitoba 125 Dysart Road, Winnipeg, MB R3T 2N2, Canada
AB: The Superior Craton, the largest region of stable Archean crust, is exposed nearly halfway across Canada, from eastern Quebec to eastern Manitoba. Westward into Manitoba, the Superior is believed to underlie the Phanerozoic sediments of the Western Canada Sedimentary Basin, but is not exposed at the surface; further north, the contact between the Superior and the Trans-Hudson Orogen are exposed along the Thompson Nickel Belt. The Superior Province is underlain by a high-velocity upper-mantle anomaly with complex internal structure; past teleseismic studies have located features in the lithosphere corresponding closely to crustal structures, indicating long-term stability of the mantle root; however, there are indications of deformation and modification of the mantle of the eastern Superior. The lithosphere beneath the westernmost portion of the Superior and its contact with the Trans-Hudson has not been examined in detail due to a lack of instrumentation. To remedy this, we have deployed a set of seven broadband teleseismic instruments in both northern and southern Manitoba. Two southern stations (in Winnipeg and Star Lake, Manitoba) were deployed in 2006; an additional five stations were deployed in 2007 in both southern (Brandon) and northern Manitoba (Grand Rapids, Jenpeg, Thompson and Gillam). Preliminary results indicate that the unusually strong shear-wave splitting known to exist beneath western Ontario continues into Manitoba; we have also successfully applied the noise cross-correlation technique to generate a surface-wave train between the Star Lake and Winnipeg stations. Once sufficient data have been recorded, we expect to perform teleseismic tomography, shear-wave splitting and surface-wave analysis over the whole of Manitoba, extend the Superior results westward, and contribute to a better understanding of Hudson Bay as a component of the Hudson Bay Lithospheric Experiment (HuBLE).
DE: 7218 Lithosphere (1236)
DE: 7270 Tomography (6982, 8180)
DE: 7294 Seismic instruments and networks (0935, 3025)
DE: 8103 Continental cratons
DE: 8159 Rheology: crust and lithosphere (8031)
SC: Tectonophysics [T]
MN: 2007 Fall Meeting