Digital Elevation Model (DEM)-Based Analysis of Surficial Sedimentary Deposits, Flathead Indian Reservation, Western Montana

This project will conduct a digital elevation model (DEM) study and mapping project of surficial deposits on the Flathead Indian Reservation (FIR) in western Montana. The surficial geology of the reservation is complex, consisting of intermingled Tertiary fan deposits and Quaternary glacial deposits. The few studies to date on this topic present conflicting interpretations which lead to varied implications regarding issues such as surface-groundwater interactions, cation-exchange and sorptive capacities of surficial deposits, liquefaction potential of the deposits in light of local seismic potential, and geologic histories related to Tertiary and Quaternary climate change.

We propose to use DEMs to identify characteristic geomorphic and topographic regimes on the FIR, coupled with various field and laboratory analytical techniques designed to determine mineralogies and textures of the surficial deposits that comprise the different geomorphic types. Preliminary field work suggests that surficial deposits may be segmented into (1) terminal and recessional moraines, many of which are subdues and possibly buried under a mantle of recent sediment, (2) dissected fan deposits that appear to consist of Tertiary alluvium and paleosols beneath a mantle of recent sediments, and (3) topographically horizontal or shallowly sloping varved clay and outwash deposits. By focusing on ~3 distinct geomorphic types that appear to characterize most surficial deposits in the region, we hope to be able to generate a predictive model based on DEMs that can be extrapolated to similar landforms across the FIR and adjacent areas. In doing so, we hope to generate a synoptic overview of geomorphology and surficial deposit characteristics.

Contact Information

Mail:	Dr. Tim Olson
	Salish Kootenai College
	P.O. Box 117
	Pablo, MT 59855