Granite Landscape in Yosemite National Park, USA

Yosemite National Park is located in California, with an area of 3,086 square kilometers and an altitude of 2,000 ~13,000 feet. It is famous for its numerous valleys, waterfalls, inner lakes, icebergs and moraines, and shows people a large number of granite reliefs caused by rare glaciers in the world. In addition, there are many rare plants and animals living at an altitude of 600 ~ 4000 meters in the park. The famous Yosemite Valley is located in the National Park. Yosemite Valley is about 12km long, 800 ~ 1800 m wide and 300 ~ 1500 m deep, which is a typical ice erosion U-shaped valley. The valley is flat and steep. Many towering granite domes, boulders and rock walls on both sides of the canyon are the most striking landscapes. The dense vegetation in Yosemite Valley is rich in water resources. The Merced River is composed of three streams, Tanaya, Iliad and Yosemite, from the high valley, which pass through the canyon and form a series of waterfalls. Among them, the famous yosemite falls is 739 meters high, which is the largest waterfall in North America and ranks third in the world.

2. Characteristics of granite landscape

The rocks that make up Yosemite National Park are mainly granite, granodiorite and adamellite (AnnHarris, 1999), which intruded into metamorphic sedimentary rocks and metamorphic volcanic rocks in Mesozoic and Cretaceous. After the shaping and transformation of Quaternary glaciation and river geology, many beautiful and spectacular scenery have been formed in the park, especially the granite landscape here, which is closely related to the transformation of Quaternary glaciation.

The granite landscape in the park is generally a U-shaped valley formed by the erosion of granite islands and hills, granite domes, boulders and glaciers.

1) NorthDome: The rock that constitutes this landscape is granite diorite. Due to the melting of the glacier covering it, the top of it expands slightly due to the decrease of pressure, and the flaky joints parallel to the outer surface are relatively developed. With the exposure of rocks, mechanical weathering will make granite pieces peel off in concentric layers. Because the vertical joints are not well developed, domes with foliation peeling will often develop in this spherical weathering of such large granite blocks. The curve at the bottom of the northern dome records the edge of the leaf peeling. Under the north dome is a cliff 1500 feet high.

Figure 4-58 NorthDome (image source:/html/sheyingjichu/2007-9/42787636810.html)