Date of Graduation

Summer 2020

Degree

Master of Science in Geography and Geology

Department

Geography, Geology, and Planning

Committee Chair

Matthew McKay

Keywords

zircon, provenance, North America, Th/U, petrochronology, detrital, Missouri River, basin

Subject Categories

Geochemistry | Geology | Sedimentology | Stratigraphy | Tectonics and Structure

Abstract

Detrital petrochronology can provide a detailed look into sedimentary provenance through integrated mineral radioisotopic ages with corresponding mineral chemistry. By combining U-Pb ages and Th/U values of detrital zircon from 13 samples collected from Quaternary sand deposits in the Upper Missouri, Yellowstone, Bighorn, Platte, Kansas, Arkansas, Mississippi, Red and Brazos Rivers, an interpretation of detailed signatures that record evidence of the evolution of the Mississippi/Missouri River drainage and the tectonic events that shaped it were observed. Low Th/U values in zircon correlate temporally to convergent magmatism, whereas, higher and more variable Th/U zircon are coeval with known extensional tectonism. Using these data, this study was able to resolve the evolution of drainage patterns from the Cretaceous to the Cenozoic. Grains found within the N. Rocky Mountains and Northern Plains samples as well as the Central Plains samples exhibited Cordilleran ages (<280 >Ma) and Th/U values

Copyright

© Sage Denali Muttel

Open Access

Share

COinS