Miocene-Pleistocene river reorganization across the Pacific Northwest and northern Rocky Mountains скачать в хорошем качестве

Miocene-Pleistocene river reorganization across the Pacific Northwest and northern Rocky Mountains

Lydia Staisch - USGS The incision rate history of the Snake River through Hells Canyon, forming North America’s deepest river gorge, has been contested for over a century. In this work, we analyze the stratigraphic history and detrital zircon U-Pb provenance of Miocene fluvial and lacustrine sandstones on either side of Hells Canyon to identify the timing and change in upstream contributing drainage area. We reconcile these data with similarly aged stratigraphic units in central Washington and southwestern Montana to identify the timing and mechanisms responsible for major changes to the Snake, upper Missouri, and Columbia Rivers since the Miocene.