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Full-Text Articles in Geology
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 …
Spatiotemporal Slip Rate Variations Along Surprise Valley Fault In Relation To Pleistocene Pluvial Lakes, Brian N. Marion
Spatiotemporal Slip Rate Variations Along Surprise Valley Fault In Relation To Pleistocene Pluvial Lakes, Brian N. Marion
All Master's Theses
Using mapped paleoshoreline features with high-resolution topographic data and obtained radiocarbon dates on paleoshoreline tufas, I documented precise fault offsets of dated features over the last 25 ka along the Surprise Valley Fault (SVF). Fault offset measured in three lake sections within Surprise Valley ranged from 3.6 m in the southern section to 14.4 m in the central section. The offset paleoshorelines are dated to the late Pleistocene (<22 >ka) and were formed during the latest impoundment of pluvial Lake Surprise since the last glacial maximum. Slip rates vary along strike, assuming a fault dip of 68° with 0.25 ± …