à base asphaltique

CONT: Les pétroles à caractère naphténique sont fort rares.

CONT: The only asphalt-base crudes produced in large amounts in Canada are Lloydminster, Coleville and Fosterton.
OBS: naphthene-base oil: It is often called asphalt-base oil, because the residue from its distillation contains asphaltic materials but little or no paraffin wax.