A geophysical and geochemical interpretation of the configuration of the Mount Peyton complex, central Newfoundland

• Published in: Atlantic Geology
• Main Authors: Miller, H. G., Thakwalakwa, S. A.M.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Atlantic Geoscience Society 1992
• Subjects: Newfoundland; Terre-Neuve
• Online Access: https://journals.lib.unb.ca/index.php/ag/article/view/1864

An integrated geophysical, geological and geochemical study of the Mount Peyton complex in central Newfoundland has provided insight into the surface and subsurface configuration of the feature. The geology, magnetics, gravity, copper, nickel and uranium data enable us to delineate and redefine the lithological boundaries of the complex and develop an appreciation of its possible configuration at depth. The geophysical modelling is consistent with earlier interpretations that the batholith consists of a gabbroic phase which was emplaced in the Botwood Group at 420 ± 8 Ma. A later granitic phase was emplaced at 390 ± 15 Ma. There is a close spatial relationship between the various lithologies and specific geophysical and geochemical signatures. Shaded relief techniques applied to the aeromagnetic data indicate that the batholith has undergone at least one phase of faulting. Magnetic modelling reveals inward dipping gabbro blocks along the exterior boundaries of the complex. The model derived from the limited gravity data is consistent with the magnetically modelled blocks based on more extensive data. The geophysical and geochemical data suggest the granitic portion of the batholith is smaller in volume, but larger' in area, than implied by the limited outcrop mapping. The geophysical modelling is consistent with a thin granitic phase and thicker gabbroic phase. RÉSUMÉ Une étude géophysique, géologique et géochimique intégrée du complexe du mont Peyton dans le centre de Terre-Neuve à fourni des indices sur la configuration de surface et souterraine du complexe. Les données géologiques, magnétiques, gravimétriques et de cuivre, nickel et uranium nous permettent de tracer et de redéfinir les contacts lithologiques du complexe et de développer une appréciation de sa configuration possible en profondeur. La modélisation géophysique est en accord avec les ...