Quartz provenance in the Mesozoic of the eastern Scotian Basin

Abstract

The provenance of quartz, the predominant framework mineral in sandstone reservoirs, is an important exploration tool in petroleum basins. An integrated approach of scanning electron microscope-cathodoluminescense (SEM-CL), hot-cathode cathodoluminescense (HCL), and petrographic microscopy using grain-by-grain comparison was used to interpret provenance of sandstones in the Bandol-1 well in the eastern Scotian Basin. Information provided by SEM-CL features, HCL colours and colour shift, and optical properties such as extinction, fluid inclusion trails and polycrystallinity were combined to distinguish different quartz types. The integration of the three techniques reduces uncertainties inherent to each individual technique. The three techniques were compared and all the characteristic features for each quartz type under the three different microscopes were summarized in detail. This study suggests that the integration of SEM-CL and petrographic microscopy appears to be enough to differentiate between major quartz types such as plutonic and metamorphic quartz, while HCL analyses are important to constrain and confirm the classification of quartz types. In addition, HCL analyses were demonstrated to be very useful in assigning detrital quartz to a specific metamorphic grade. Previous detrital mineral and geochronological studies of the same samples were also used for comparison and better understanding of potential provenance sources. Possible sources of sediments to Bandol-1 well were suggested in the Gander terrane of southern Newfoundland, Humber terrane of western Newfoundland, and part of southern Dunnage terrane.