Seismic structure of the crust and upper mantle in the Peace River Arch region ...

• Main Author: Zelt, Colin Andrew
• Format: Text
• Language: English
• Published: University of British Columbia 2010
• Subjects: Peace River
• Online Access: https://dx.doi.org/10.14288/1.0052504; https://doi.library.ubc.ca/10.14288/1.0052504

The Peace River Arch (PRA) is a regional ~E-W trending geological structure within the Western Canada Sedimentary Basin whose Phanerozoic history of vertical movements is anomalous with respect to the basin as a whole. Four intersecting ~300-km-long reversed refraction lines within the PRA region in northwestern Alberta and northeastern British Columbia have been interpreted for crustal and upper mantle P-wave velocity structure. The data have been analyzed using a new two-dimensional ray-trace forward modelling algorithm to match travel times and amplitudes of first and coherent later arrivals. An inversion of first arrival travel times along a fan shot profile has been performed to constrain crustal thickness northwest of the arch in a region not sampled by the in-line profiles. 5-waves and the observed spectra of the refraction data have been analyzed to infer a regional Poisson's ratio and Q structure, respectively. The consistency of the seismic models with the observed Bouguer gravity data was studied. ...