Overview
- The paper, published August 17, 2026 in Geology, argues that breakup of the ancient supercontinent Rodinia produced a continent‑scale, 1‑kilometer‑high escarpment that migrated inland and exhumed deep crustal rocks now seen in the Grand Canyon.
- Authors led by Thomas Gernon built the case with landscape‑evolution simulations and plate reconstructions run over hundreds of millions of years rather than from a single new field discovery.
- Their models estimate as much as about eight kilometers of rock were removed near the migrating escarpment, a scale of erosion the team links to spatial differences in the Great Unconformity.
- The study does not replace the established view that the Colorado River incised the modern canyon in the last five to six million years but proposes the river cut into basement that had been exposed much earlier by rift‑related erosion.
- If supported by field tests, the hypothesis would change how geologists read North American drainage and sediment records and will likely prompt targeted field mapping and geochronology to test the model's predictions.