The Grand Canyon, stunning as it is, goes often unnoticed for the epic geological story it unfolds. Visitors are taken aback by its sheer beauty, but are unphased or ignorant of the sheer history on its walls. Each formation is a standalone eon on the timeline of Earth history, filled with the fossils and sediments of a unique landscape.
The bottom of the canyon is far back as we can see in the history of deposition that the Colorado River eroded. At this time it was mainly volcanic sediment. At other times it was awash by marine deposition, forming limestone surfaces under a prehistoric ocean. Later it was a great swamp, full of siltstone and amphibious fossils. Later still it was a vast ocean of tall dunes, rising at least 400 feet, as that is how tall this portion of the Canyon wall is, peppered by desert reptile fossils and sandstone. It was then overlain by another shallow ocean before being uplifted by major orogeny, the fault lines creating opportunities for new rivers like the Colorado to erode vast canyon-scapes of underlying rock and sediment.
Each layer is like a snapshot in time, separated by a relatively short period of erosion. It is a magnificent architecture of earthen materials, folded intricately over time by God's patience. There is no greater place to study the history of Earth than here.
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