Physical Sciences and Mathematics Commons^™

Fluvial Geomorphic And Hydrologic Evolution And Climate Change Resilience In Young Volcanic Landscapes: Rhyolite Plateau And Lamar Valley, Yellowstone National Park, Benjamin Newell Burnett

Earth and Planetary Sciences ETDs

Quaternary volcanism associated with the last caldera cycle in Yellowstone National Park included emplacement of ash-flow tuffs, massive rhyolite flows ranging from 79 to 484 ka, and valley-filling basalts. This study examines (1) the evolution of spring hydrology with flow age on the Rhyolite Plateau, (2) initial development and evolution of stream networks on the rhyolite flows, and (3) the impact of the 630 ka caldera formation and volcanic flow emplacement on Lamar Valley incision rates.

Integrated stream networks formed within 79 kyr on the Rhyolite Plateau. Incision is focused on steep flow margins and knickpoints and is dependent on …

Birth And Evolution Of The Rio Grande Fluvial System In The Last 8 Ma:Progressive Downward Integration And Interplay Between Tectonics, Volcanism, Climate, And River Evolution, Marisa N. Repasch

Earth and Planetary Sciences ETDs

The Rio Grande-Rio Chama (RG-RC) fluvial system has evolved dramatically over the last 8 Ma, undergoing channel migrations, drainage capture and integration events, volcanic damming, and carving and refilling of paleocanyons. Volcanism concurrent with the development of the river system provides a unique opportunity to apply multiple geochronometers to the study of its incision and drainage evolution. This paper reports 19 new ⁴⁰Ar/³⁹Ar basalt ages and 19 detrital mineral samples (zircon and sanidine) collected from RG-RC alluvium overlain by dated basalt flows in the context of a compilation of published ⁴⁰Ar/³⁹Ar basalt ages. The …