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TitreImaging the Moho and Vp/Vs ratio in the western Superior Archean craton with wide angle reflections
AuteurKay, I; Musacchio, G; White, D; Asudeh, I; Roberts, B; Forsyth, D; Hajnal, Z; Koperwhats, B; Farrell, D
SourceGeophysical Research Letters vol. 26, no. 16, 1999 p. 2585-2588, (Accès ouvert)
Séries alt.Commission géologique du Canada, Contributions aux publications extérieures 1998184
Documentpublication en série
Mediapapier; en ligne; numérique
ProvinceManitoba; Ontario
SNRC42D; 42E; 42L; 42M; 43D; 52; 53A; 53B; 53C; 53D
Lat/Long OENS -96.0000 -86.0000 53.0000 48.0000
Sujetsdiscontinuité de Mohorovicic; Archéen; craton; topographie; ondes P; ondes transversales; croûte continentale; plutons; géophysique; géologie structurale
Illustrationslocation maps; seismic profiles; tables
Diffusé1999 08 15
Résumé(disponible en anglais seulement)
A refraction/wide-angle reflection survey in northwestern Ontario investigated the Archean Superior Province of the Canadian Shield. Images of apparent Moho topography were produced from both the PmP and SmS Moho wide angle reflections. The average Moho depth is 41 km, and average P- and S-wave velocities 6.6 and 3.8 (±0.05) km/s respectively. The Moho dips southward from 39.5 to 42 km depth over roughly 400 km. From ratios of S and P travel times to the Moho, profiles of Vp/Vs were constructed. The average Vp/Vs ratios are 1.74 and 1.76 for on the E-W and N-S lines (Poisson's ratio s = 0.253 and 0.262 respectively). Vp/Vs profiles show a sharp increase from west to east and a gradual increase from north to south, correlating with the distribution of more felsic continental crust and composite crust in the Western Superior.