A high resolution seismic reflection study of the carboniferous Bay St. George subbasin, western Newfoundland

Abstract

A seismic reflection profile from onshore Bay St. George Subbasin in western Newfoundland was reprocessed and reinterpreted to determine the structure and extent of the Carboniferous rocks. The main emphasis of reprocessing was placed on velocity analyses and dip move-out (DMO). The quality of the data was improved significantly by the reprocessing. A few features which had not been discovered before became evident. An example of this is an unconformity at a depth of 3.0 km to 5.0 km. -- The basin has the configuration of a half graben dipping to the east. The maximum thickness of the Carboniferous sediments is about 5 km in individual depocentres. The basin appears to be bounded downwards by unconformity "U", which separates the Carboniferous rocks from either Lower Palaeozoic rocks or Precambrian rocks. -- The fault system is very complex. A few faults correspond to the surface geology. The pattern of faults suggest that the basin was opened by strike slip movements and later deformed by compressional forces.