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Float Trip! The Lower San Juan River

Note: This trip is being run by the Rocky Mountain Association of Geologists in association with the Fort Lewis on the Water (FLOW) program. Transportation from FLC and back, food, rafting gear, guides and some camping equipment are all included in the trip price.

Dates:  June 4th-8th

Leaders: Drs. Gary Gianniny, FLC and Rip Langford, UTEP

Price: $1,400 for RMAG members / $1,500 non-members

Transportation:  Provided from Fort Lewis College and back

Limit: 24 total



Come join the RMAG for five days and four nights on the lower San Juan River. Traveling with renowned geologists Dr Gary Gianniny (Fort Lewis College) and Dr Rip Langford (University of Texas at El Paso), and rafting professionals from Fort Lewis on the Water program, we will enter the Glen Canyon National Recreation Area and float through goosenecks carved deep into the sedimentary section to experience dramatic geology, fabulous outcrops, and world-class hiking opportunities.

The lower San Juan River exposes the Pennsylvanian Hermosa Group, deposited on the stable, broad, shallow shelf near the western margin of the Paradox Basin.  Lithologies outcropping along the river are outcrop analogs for producing intervals at the giant Aneth Oil Field, satellite fields in the Paradox Basin, and at Barker Dome & Ute Dome fields on the Four Corners Platform.  Geologists rafting through these folded Pennsylvanian strata can examine phylloid algal and microbial bioherms (oil and gas reservoirs), and organic-rich black shales (source rocks).   Higher up in the section, cross-bedded carbonate grainstones appear in the younger Honaker Trail Formation, followed upwards by non-marine terrigenous sediments in the Permian Lower Cutler Group, including rare rhizolith channel-fill conglomerates  Spectacular exposures of the overlying Cedar Mesa Sandstone provide a superb view of the complex facies of a mixed wet eolian and fluvial system.

For more information open this pdf: Lower SJ Float Trip