Yosemite’s geology can be tough to understand! If most people heard words like batholiths,pyroclastic and subduction not many of them would know what they are or how they apply to Yosemite! Instead, here is an attempt to break down the geology of Yosemite into something a little more understandable.
Yosemite is a glaciated landscape; that is, the beauty and scenery viewed by many is the result of the interaction of glaciers and underlying rocks. Landforms that are the result of glaciations include: U-shaped canyons, jagged peaks, rounded domes, and waterfalls.
Yosemite Valley is one location in the park that has changed its appearance considerably since glacial times. Glaciers dumped enormous quantities of rock and rubble at its western end, stopping Yosemite Valley’s outflow and covering its floor with water. Lake Yosemite was formed.
Over 10,000 years, the lake was filled with rock and silt washed down from the Park’s higher regions, and the valley’s flat, dry floor (as we know it today) was created.
Today, Yosemite’s landscape continues to change. While geological processes are not dramatic, erosion still continues, avalanches still occur, and rockslides are still common. The geologic story continues in Yosemite and provides us with a better understanding of the Park’s famous scenery.