Cave records reveal recent origin of North America's deepest canyon.

ABSTRACT: We explore how and when Hells Canyon, North America's deepest river gorge (~2,400 m deep), formed, addressing these fundamental questions first posed by W. Lindgren [The Gold Belt of the Blue Mountains of Oregon (1901)]. Existing hypotheses about the canyon's formation and timing of incision remain speculative due to a lack of direct constraints and geomorphic analysis in the canyon. Herein, we combine cosmogenic nuclide dating of cave-bound river deposits, river profile analysis, and numerical modeling to provide the first direct age constraints and systematic analysis of incision processes at work in Hells Canyon. Our study reveals a significant drainage capture triggered rapid incision at ~2.1 ± 1.0 Ma, establishing the Snake River's modern route into the Columbia River system. T

SUBMITTER: Morriss MC 

PROVIDER: S-EPMC12130896 | biostudies-literature | 2025 May

REPOSITORIES: biostudies-literature