info:eu-repo/semantics/article
VELOCITY DIFFERENCES IN THE MIDDLE-LOWER CRUST ACROSS THE PROTEROZOIC NORTH AUSTRALIAN CRATON
VELOCITY DIFFERENCES IN THE MIDDLE-LOWER CRUST ACROSS THE PROTEROZOIC NORTH AUSTRALIAN CRATON
Autor
FINLAYSON, D. M.
Institución
Resumen
Seismic refraction surveys conducted in two onshore and one offshore areas of the Proterozoic North Australian Craton indicate complex P-wave velocity variations in the upper 20 km of crust compatible with an assemblage of younger and older metamorphic rocks intruded by granites which are overlain by a 2 km thick sedimentary sequence offshore. In the middle-lower crust. between 20 and 50 km depth there appears to be an increase in P-wave velocity from east to west and from south to north. These trends can be interpreted as indicating a greater proportion of high-velocity granulites being emplaced at higher leveis in the crust. Seismic refraction surveys conducted in two onshore and one offshore areas of the Proterozoic North Australian Craton indicate complex P-wave velocity variations in the upper 20 km of crust compatible with an assemblage of younger and older metamorphic rocks intruded by granites which are overlain by a 2 km thick sedimentary sequence offshore. In the middle-lower crust. between 20 and 50 km depth there appears to be an increase in P-wave velocity from east to west and from south to north. These trends can be interpreted as indicating a greater proportion of high-velocity granulites being emplaced at higher leveis in the crust.