<Li> United Arab Emirates </Li> <Li> North America: <Ul> <Li> The Appalachian Basin: <Ul> <Li> Pennsylvania Grade Crude Oil </Li> </Ul> </Li> <Li> The Mid-Continent Oil Field: <Ul> <Li> Louisiana Sweet </Li> <Li> Texas Light Sweet (a.k.a. West Texas Intermediate) </Li> </Ul> </Li> <Li> The Trenton Formation: <Ul> <Li> Ontario </Li> </Ul> </Li> <Li> The Bakken Formation of <Ul> <Li> Manitoba </Li> <Li> Montana </Li> <Li> North Dakota </Li> <Li> Saskatchewan </Li> </Ul> </Li> </Ul> </Li> <Ul> <Li> The Appalachian Basin: <Ul> <Li> Pennsylvania Grade Crude Oil </Li> </Ul> </Li> <Li> The Mid-Continent Oil Field: <Ul> <Li> Louisiana Sweet </Li> <Li> Texas Light Sweet (a.k.a. West Texas Intermediate) </Li> </Ul> </Li> <Li> The Trenton Formation: <Ul> <Li> Ontario </Li> </Ul> </Li> <Li> The Bakken Formation of <Ul> <Li> Manitoba </Li> <Li> Montana </Li> <Li> North Dakota </Li> <Li> Saskatchewan </Li> </Ul> </Li> </Ul> <Li> The Appalachian Basin: <Ul> <Li> Pennsylvania Grade Crude Oil </Li> </Ul> </Li>

Price difference between sweet and sour crude oil