The Wave is a spectacular undulating rock formation in the Coyote Buttes of the Paria Canyon-Vermilion Cliffs Wilderness in Arizona. It originated from sand dunes that formed about 150 million years ago during the Jurassic Period and eventually lithified into Navajo Sandstone.
This Jurassic dune field resembled today’s Sahara, a vast desert that stretched across what is now the American Southwest. As layer upon layer of sand accumulated, the buried dunes gradually reached the groundwater table and became saturated with water. Dissolved minerals in the groundwater, including calcium, cemented the individual sand grains together, slowly transforming the buried dunes into solid rock.
Navajo Sandstone is the most widespread rock formation on the Colorado Plateau. In the area of The Wave, the wind-shaped architecture of the ancient dunes has been preserved in extraordinary detail. Every slanting line in the rock represents the cross-bedding of a former dune, where sand repeatedly cascaded down its steep, leeward slope.
The geology of The Wave seems to have outdone itself by transforming the normally white to salmon-colored sandstone into an explosion of deep reds and yellows. This extraordinary palette developed when groundwater carrying traces of manganese and iron oxide minerals penetrated the buried dunes. Subtle differences in the chemical composition of these minerals stained both the sand grains and the cement binding them together, creating the astonishing spectrum of colors now exposed at The Wave.
The Paria River, a tributary of the Colorado River, carved an intricate network of canyons, cliffs, and buttes into the Coyote Buttes. Summer flash floods triggered by thunderstorms further sculpted the landscape into gently rounded, U-shaped troughs. The sandstone weathers most readily along preexisting fractures within the dune cross-bedding, while the abrasive action of windblown sand has further sculpted The Wave into its present form.
Today, the Coyote Buttes and the famous Wave stand at an elevation of 1,590 meters (5,220 feet). Uplifted along with the entire Colorado Plateau, this landscape once again finds itself in an arid environment, largely cut off from moisture arriving from the Pacific by the Sierra Nevada for most of the year. Only winter low-pressure systems and summer monsoon thunderstorms deliver significant rainfall. The resulting flash floods continue to shape The Wave, although their occurrence is highly irregular.
This fanciful landscape of fabulously sculpted sandstone creates an atmosphere in which one would hardly be surprised to see a herd of dinosaurs wandering through the scenery. In fact, Navajo Sandstone contains traces of dinosaur activity. Their footprints, tracks, disturbances, and droppings are preserved throughout the region. These dinosaurs once roamed a world of sand.
