Geological Survey of Canada, Current Research (Online) no. 2005-D1

Book excerpt: This paper presents preliminary results from field observations on the Lower Silurian La Vieille Formation in north-east New Brunswick regarding the extent of early hydrothermal dolomitization, a critical element for assessing hydrocarbon potential. Six stratigraphic sections of the Formation were carefully examined for facies architecture and evidence of hydrothermal alteration of limestone facies. Features of interest included early fractures, brecciation & dissolution associated with early fractures, large-scale collapse of sections, fracture-filling cements, and synsedimentary tectonic instability. The findings provide critical information pertinent to the hydrocarbon reservoir potential of these rocks.