Locale: The Grand Canyon is 277 river miles (446 km) long, up to 18 miles (29 km) wide, and a mile (1.6 km) deep. Despite its being a very well-known natural geologic formation, there isn’t complete consensus among scientists as to how the canyon was formed. As the LiveScience website says,
The specific geologic processes and timing that formed the Grand Canyon spark lively debates by geologists. The general scientific consensus, updated at a 2010 conference, holds that the Colorado River carved the Grand Canyon beginning 5 million to 6 million years ago.
However, recent advances in dating techniques have upended the notion of a uniformly young Grand Canyon. The new approach determines when erosion uncovered rocks in the canyon. The big picture: there were two ancestral canyons, one in the west and one in the east. And the western canyon may be as old as 70 million years.
In a more recent timeframe,
García López de Cárdenas, an explorer from Spain, was the first European known to have viewed the Grand Canyon. As a member of the 1540 expedition of Francisco Vásquez de Coronado, he led a party from Cibola, the Zuñi country of New Mexico, to find a river mentioned by the Hopi. After a 20-day journey he was the first white man to see the Colorado River and the Grand Canyon.
An avid outdoorsman, President Theodore Roosevelt was an enthusiastic admirer of the Canyon, but it would be years before it became our fifteenth national park: in 1919, the Grand Canyon National Park Act was finally signed by President Woodrow Wilson.
Weather: High 100 at Grand Canyon, Low 60. Mostly sunny, afternoon thunderstorm
Creatures: Bighorn sheep (Ovis canadensis), Abert’s squirrel (Sciurus aberti)
Itinerary: Hart Prairie to US 180, to Valle, to Tusayan, to Grand Canyon Village, and return
Excursions: Grand Canyon (Shoshone Point Trail, El Tovar Restaurant, Bright Angel Trail, Kolb Studio)
Guest Speaker: Bob Jensen, former Hart Prairie Caretaker (evening)
Reflections: The Canyon is indeed grand! I stood and stared and tried to take it all in: the depth, the colors, the covert wildlife, the immense span of time represented.
Images: Visit to the Grand Canyon (click on the 3 vertical dots at the top right to select slide show)