Students enrolled in GEOL 112 (Historical Geology) participate in a day-long field trip each Spring semester at Mesa State College. Led by Dr. Rex Cole, the field trip begins in Grand Junction and includes stops at Palisade, Parachute, Anvil Points/Rulison, Rifle Gap Dam, Glenwood Canyon, Dotsero, and Sweetwater Creek.
 

A recumbent fold in Glenwood Canyon

Students at Rifle Gap digging for fossils

The initial stop in Palisade includes geographic orientation and discussion of major physiographic features such as the Grand Mesa, the Book Cliffs, and the Uncompahgre Plateau, which includes the Colorado National Monument. Discussion covers Laramide orogenic structures of the Uncompahgre uplift and the Piceance Creek Basin. In Parachute, students receive an overview of Paleocene-Eocene stratigraphy, which includes the Wasatch and Green River Formations. The Wasatch Formation contains mammal fossils, while the Green River Formation is known for its kerogen-rich oil shales. At Anvil Points, the group investigates the New Paraho oil shale operation, Pleistocene surficial deposits of the Battlement Mesa area, natural-gas production in the south-central Piceane Creek Basin, and Project Rulison - a nuclear detonation site to stimulate natural-gas production. At Rifle Gap Dam, students view the Grand Hogback monocline and White River uplift. Rifle Gap Reservoir lies in a strike-valley bounded by the Grand Hogback to the south, while the other wall is formed by the Dakota Formation. Students also view karst features of the White River Plateau and travertine caves at Rifle Falls. The next stop is Dotsero, where the youngest volcano in Colorado occurs, dated approximately 4,000 years old. The Dotsero cinder cone formed as a vent in the bottom of a small gully that was tributary to the Eagle River. The initial basalt extrusion from a dike blocked the gully and spilled into adjacent drainage channels. The route from Dotsero to the final stop at Sweetwater Creek, travels through the Pennsylvanian Belden Formation with fossiliferous limestones and shales, and the Eagle Valley evaporites. An excellent example of a recumbent fold/thrust fault in the Belden Formation is visible from the road. At Sweetwater Creek, students search for fossils in the Belden Formation, which include trilobites, brachiopods, and bryozoans.

Contact Dr. Rex Cole for more information rcole@mesastate.edu