RUI: Collaborative Research: Quantifying the roles of tectonic activity and climate as drivers of glacial-interglacial landscape evolution in the Teton Range, Wyoming

Idaho State University, Pocatello ID

Investigators

Abstract

The interplay of tectonics and climate is an essential aspect of mountain landscape evolution. Research efforts focusing on the interactions of mountain landscapes with climate and tectonism, especially those directed toward quantitative reconstructions of climatically and tectonically driven disturbances, are fundamental to understanding the past and future evolution of Earth's surface, and are critical for human adaptation and resource conservation efforts. This project focuses on the Teton mountain range in Grand Teton National Park, WY, where past climatic and tectonic disturbances are unusually well-recorded by glacial landforms, fault scarps, and lake sediment archives, all of which can be precisely dated. The overarching goals of this project are to quantify the influences of tectonic-driven disturbances (earthquakes, landslides) and climate-driven changes and disturbances (e.g. deglaciation, glacier fluctuations, vegetative shifts, fire occurrence) on alpine erosion rates and landscape evolution operating during the late Pleistocene and Holocene (past 25 ka). Specifically, the study combines detailed landform mapping, 10Be surface exposure dating, paleoseismic fault trenching, lake seismic surveys, and lake sediment cores to develop complementary records of: i) glacier fluctuations, including the timing and character of deglaciation and Neoglaciation; ii) environmental variability along the elevation gradient of the Teton range; and iii) earthquake timing and frequency related to postglacial ruptures of the Teton fault. The highly-active tectonic setting, distinctive geomorphology, and relatively pristine ecosystem of the Tetons present an exceptional opportunity for this research. Moreover, the integration of these techniques will provide comprehensive insights into the couplings and feedbacks among climatic and tectonic processes that modify all mountain landscapes over diverse length and time scales.