Half of the Yosemite story

For many visitors, the dramatic profile of Half Dome stands as the symbol of Yosemite National Park in northern California.

Half Dome is composed of granite, an igneous rock that forms deep within the Earth’s crust by intrusion of molten magma from below.

But how does a rock that is formed deep within the Earth’s crust come to tower over the modern landscape?

Long after the magma cooled to form large granite bodies, called plutons, tectonic forces pushed the area upwards. As the region was uplifted, erosion stripped away the less-resistant layers of rock overlying the granite plutons, eventually leaving the granite exposed to dominate the landscape.

Uplift and erosion are still active in the area today, and Yosemite’s landscape continues to evolve.

Photo of Half Dome is from here.