PTYS 590: Planetary Geology Field Studies - The Channeled Scablands
By Vic Baker and Jack Holt
The PTYS 590 Planetary Geology Field Studies Course was a bit different this semester. Firstly, it operated from a rather complete field conference facility in the Dry Falls/Sun Lakes State Park of Washington state. Named Camp Delany, it provided a central base for 9 days of intensive geological and geophysical investigations of the Channeled Scablands landscapes in east-central Washington, where spectacular erosional and depositional features resulting from megafloods relevant to Mars are located. Our camp had 8 spacious cabins, a complete restroom building with showers, and a large recreation hall that served as kitchen and dining hall, with ample space for equipment storage and preparations, evening presentations, and discussion groups.
Another difference this semester was the trip format. Students from Tucson arrived in the late afternoon of Oct. 12 at the Dry Falls Visitors Center, where the head ranger provided an excellent regional overview. Days 2 and 3 involved extensive field drives through the area, including particular attention to potential locations for subsequent intensive investigations to be carried out by teams of students, course instructors, and visiting scientists. Professor Jerome Lesemann, University of Vancouver Island, Canada, participated in these trips.
On days 4 through 8, the various topical field investigations were in full force. The two course instructors, Jack Holt and Vic Baker, were joined by LPL associate professor Lynn Carter and postdoctoral research associate Dr. Stefano Nerozzi, as well as by local experts Dr. Jim O’Connor of the U.S. Geological Survey, and geologist Bruce Bjornstad, the author of the most authoritative guidebooks on the regional geology and an expert on drone photography. The core croup of 16 University of Arizona students was joined by local participants from the University of Washington, Eastern Washington University, and Mount Hood Community College in Oregon.
The various field investigative teams were divided into groups that focused on (1) ground penetrating radar studies of the basalt bedrock and the megaflooding depositional forms (gravel bars and dunes), (2) high-resolution topographic analysis of boulders emplaced by the mega-flooding, and (3) geological studies of bedrock erosion features, notably the rock basins in Moses Coulee. These studies resulted in some interesting, new findings that may be publishable. In general, the students felt that the immersive approach was valuable, providing first-hand experience into how geological and geophysical investigations can lead to interesting new insights into geologic processes.
The final day of our trip involved cleaning up the camp, travel and returning to Tucson. However, the previous day’s field investigations culminated in a wonderful barbeque dinner organized by the Wenatchee chapter of the Ice Age Floods Institute and held at the home of the chapter president Ken Lacy, whose back yard provided a spectacular sunset view of the gravel dune field emplaced by the cataclysmic flooding.
Support the LPL Graduate Field Trip by donating to the Wilkening-Sill endowment.
Course participants and leaders on a the rim of a rock basin eroded into the Columbia River Basalt by high-energy mega-flooding. This site is within a mile of the Camp Delany field venue. (Photo by Roberto Jose Aguilar Martinez)
Course participants and leaders studying an immense boulder of Columbia River Basalt that was eroded by the high-energy megaflooding and transported to the Ephrata Fan depositional comples. The smaller boulders in the foreground are composed of granite that occurs more than 70 kilometers upstream of this site. (Photo by Roberto Jose Aguilar Martinez)
