Kings Canyon National Park - Geology

Geology

Kings Canyon is a wide glacial valley featuring tall cliffs, a meandering river, green vibrant meadows and waterfalls. A few miles outside the park, Kings Canyon deepens and steepens becoming arguably the deepest canyon in North America for a short distance. The confluence of the South Fork and Middle forks of the Kings River lies at 2,260 feet (690 m), while towering above the rivers on the north side of the canyon is Spanish Peak, which is 10,051 feet (3,064 m) tall.

Most of the mountains and canyons in the Sierra Nevada are formed in granitic rocks. These rocks, such as granite, diorite and monzonite, formed when molten rock cooled far beneath the surface of the earth. The molten rock was a by-product of a geologic process known as subduction. Powerful forces in the earth forced the landmass under the waters of the Pacific Ocean beneath and below an advancing North American Continent. Super-hot water driven from the subjecting ocean floor migrated upward and melted rock as it went. This process took place during the Cretaceous Period, 100 million years ago. Granitic rocks have speckled salt and pepper appearance because they contain various minerals including quartz, feldspars and micas.

While geologists debate the details, it is clear that the Sierra Nevada is a young mountain range, probably not more than 10 million years old. Incredible forces in the earth, probably associated with the development of the Great Basin, forced the mountains to grow and climb toward the sky. During the 10 million years at least four periods of glacial advance have coated the mountains in a thick mantle of ice. Glaciers form and develop during long periods of cool and wet weather. Glaciers move through the mountains like slow-motion rivers carving deep valleys and craggy peaks. The extensive history of glaciation within the range and the erosion resistant nature of the granitic rocks that make up most of the Sierra Nevada have together created a landscape of hanging valleys, waterfalls, craggy peaks, alpine lakes and glacial canyons.