Machu Picchu, Peru

Steven Dutch, Professor Emeritus, Natural and Applied Sciences, University of Wisconsin - Green Bay

Machu Picchu, Peru is a world famous tourist attraction. It was a ceremonial center and place of refuge for the Incas, and the Spanish conquistadores never discovered it. It remained hidden in the forests until a Yale archeologist named Hiram Bingham rediscovered it in 1911.

Even though Machu Picchu is only 200 miles from the Pacific Ocean, the Urubamba River below it flows via the Amazon to the Atlantic, over 2,000 miles away. The Urubamba makes a gigantic Z bend around Machu Picchu. Deep, winding valleys like this tell a story. They can only have been cut by rivers that were already winding before the valleys began to be eroded. If the river were straight and then began to wind after it had cut a deep valley, all the rock on the insides of the bends would have been cut away.

The upper slopes of the mountains are steep, but the lower half of the canyon is hemmed in by vertical cliffs. This pattern indicates that not long ago, the Andes, which were already rugged, were uplifted even higher and the river has had time enough only to cut a narrow gorge.

The ruins of Machu Picchu are at 13^o 09' 48" S, 72^o 32' 46" W. The sharp peak beyond the ruins is at 13^o 09' 20" S, 72^o 32' 49" W. The steep rounded ridge beyond the river is at 13^o 10' 53" S, 72^o 31' 37" W.

Machu Picchu, Peru, A Few Million Years Ago
Machu Picchu, Peru, After Accelerated Uplift

Original Scenes

(author's image)

Possible Coloring

Return to Geology Coloring Book Index
Return to Professor Dutch's Home Page

Created 25 November 2005, Last Update 15 January 2020