SHIMELD, JOHN W., Department of Geology, Dalhousie University, Halifax, Nova Scotia, Canada

ABSTRACT: Fault-Related Fluid Migration in the Jeanne d'Arc Basin, Offshore Eastern Canada

Many examples exist where faults have been invoked as pathways for vertical fluid migration. However, the precise connections between faulting and fluid migration are poorly understood, especially in sedimentary basins. In particular, there is a need for more quantitative approaches in describing the style, timing, and volume of fault-related fluid migration.

To document evidence of fault-related fluid migration, 13 wells that

intersect fault zones in the Jeanne d'Arc basin were sampled for fission track, petrographical, and fluid inclusion studies. Fission track analysis was used successfully in a previous study to detect paleo-thermal anomalies, possibly related to venting of overpressured reservoirs, in the Scotian basin (offshore eastern Canada). Similar techniques, involving forward and inverse computed models, are used in the current study to estimate the thermal history of the Jeanne d'Arc samples.

This work, coupled with detailed 3-D seismic interpretation and well-log analysis, is providing the basis for developing and refining models of fault-related fluid migration. For example, both episodic (e.g., "fault-valve" and "seismic pumping") and continuous fluid migration models exist, but it is not clear which is most appropriate in a sedimentary basin setting. At a more general level, the project will be useful for hydrocarbon exploration and production strategies in the Jeanne d'Arc basin, and may have implications for research areas such as earthquake prediction and nuclear waste disposal.

AAPG Search and Discovery Article #90987©1993 AAPG Annual Convention, New Orleans, Louisiana, April 25-28, 1993.