Geochemical and petrographic characterization of the Upper Ordovician Utica Shale, southern Quebec, Canada

The results suggest that matrix bitumen formed during migration and dissemination of hydrocarbon into the clay fraction of the rock. This is associated with significant bacterial sulfate reduction possibly in the early stages of generation and migration of oil. It appears that the porous siltstone facies in the deeply buried section of the Utica Shale acts as a reservoir for the migrated bitumen from organic-rich strata within the section and/or possibly overlying source rock.