Pore spaces partially filled with oil to the extent that oil does not flow out when disturbed.
Subsurface Oil Descriptions OR, Oil residue
Sediments are visibly oiled with black/brown coats or covered on the clasts (individual sediment particles) but little or no residue in pore spaces. Modifiers are Heavy HOR , Moderate MOR, and Light LOR.
Subsurface Oil Descriptions OF, Oil Film
Sediments are lightly oiled with a film or stain on the clasts.