2015 GSA Annual Meeting in Baltimore, Maryland, USA (1-4 November 2015)

Paper No. 310-7
Presentation Time: 9:00 AM-6:30 PM

GLACIAL AND PERIGLACIAL GEOLOGY OF YANKEE BOY BASIN, CO: A MAPPING PILOT PROJECT USING AN UNMANNED AERIAL VEHICLE


GAMACHE, Kevin, Water Management & Hydrologic Science Graduate Program, and Office of the Vice President for Research, Texas A&M University, College Station, TX 77843, GIARDINO, John R., Department of Geology and Geophysics, High Alpine and Arctic Research Program, Texas A&M University, Department of Geology and Geophysics, Texas A&M University, College Station, TX 77843-3115, ALLEN, Hunter, Department of Geology & Geophysics, High Alpine & Arctic Research Program (HAARP), Texas A&M University, College Station, TX 77843 and ROWLEY, T., Geology and Geophysics, Texas A&M University, College Station, TX 77840, krgamache@tamu.edu

The glacial deposits of Yankee Boy Basin have been mapped previously at a scale of 1:24,000 with all the deposits generalized as a Quaternary unit. Holocene talus and rock glaciers have been mapped and also generalized as Quaternary units. Because mapping in high alpine regions is time consuming, exhausting and expensive, no detailed mapping of the various glacial and periglacial landforms has occurred. To reduce time, exhaustion and expenses, we supplemented our field mapping with imagery acquired with an Unmanned Aerial Vehicle (UAV). Our map of the glacial and periglacial deposits in the basin was constructed at a scale of 1:5,000, which facilitated detailed mapping of moraines, stone polygons, stone stripes, avalanche chutes, protalus ramparts, rock glaciers, talus cones, slush avalanche deposits, Tertiary volcanics, and water features.

We used USG aerial photography and orthophoto quads, Google Earth Pro® imagery, and imagery acquired with a Phanton 2 UAV. We used the UAV to acquire imagery from various altitudes ranging from 5m to 20m. Collected imagery was both vertical and panoramic. The vertical images were corrected and overlaid on DEMs of the area. The various images were entered into ArcGIS and a composite, mosaiced image was produce. This image served as the base for mapping. As we collected imagery, deposits were investigated in the field. The UAV provided an inexpensive way to collect images; however, it was not without challenges. As a sidelight to the mapping, we learned some important lessons of using a UAV in a high, alpine environment. Flying a UAV in thin air is tricky, and was further complicated by a constant breeze and wind gusts. We discovered morning, with relatively calm air, was the best time for flying the UAV. Afternoon heating of the air resulted in turbulent air. The standard propellers that come with the Phantom 2 are not suited for use at high elevations. We found wider propeller blades proved the needed lift for the UAV.

This map is part of a larger project to create a detailed map of the glacial and periglacial deposits of the San Juan Mountains.