Natural History Wanderings

Berkeley News answers the question of how old is Yosemite Valley?

Did it all start 50 million years ago, when the granite through which the valley cuts was first exposed to the elements? Was it 30 million years ago, when data suggest canyons in the southern Sierra Nevada began to form? Did the valley only begin to form after the Sierra tilted toward the west some 5 million years ago, or was it mostly due to glaciers that formed in a cooling climate 2 to 3 million years ago?

Geologists from the University of California, Berkeley, employed a novel technique of rock analysis to get a more precise answer, and concluded that much of Yosemite Valley’s impressive depth was carved since 10 million years ago, and most likely even more recently — over the past 5 million years. This shaves about 40 million years off the oldest estimates.

Read full story at  How old is Yosemite Valley? | Berkeley News