Geology 3 Field Assignment By: Monica Royer*Pictures are from my personal photo album
Yosemite The area that covers Yosemite National Park is 761,268 acres. It is located in the Sierra Nevada mountain range. Each year there is more than 3.7 million people that visit Yosemite. The national park is 95% wilderness. “The geology of the Yosemite area is characterized by granitic rocks and remnants of older rock. About 10 million years ago, the Sierra Nevada was uplifted and then tilted to form its relatively gentle western slopes and the more dramatic eastern slopes. The uplift increased the steepness of stream and river beds, resulting in formation of deep, narrow canyons. “ “Archaeological findings have indicated that Yosemite Valley and other areas presently within park boundaries have been inhabited by human beings for over 4000 years. At the time the park area was first visited by United States citizens in 1833 the area was inhabited by Miwok Indians and periodically visited by Paiutes who lived east of the park in the Mono Lake area.” http://www.shannontech.com/ParkVision/Yosemite/Yosemite.html http://en.wikipedia.org/wiki/Yosemite_National_Park
Formation of Yosemite Valley “The area which now comprises Yosemite National park was once covered by gentle, rolling hills. The Merced River flowed through this valley fairly slowly. However, geological forces pushed the hills and mountains higher and higher, and the Merced River flowed more quickly and violently. It increasingly cut a deeper, sharper, v-shaped valley through the terrain. “ “Several periods of glaciation caused major changes to the valleys and landforms. Glaciers 2000 feet thick flowed through the valley carved by the Merced. These glaciers carved away the bottom of the valley from a V- to the broader U-shape which is seen today.”http://www.shannontech.com/ParkVision/Yosemite/Yosemite.html
Formation of Yosemite Valley “At the end of the glacial period the valley was actually much deeper that what is seen today, and a large body of water known as Lake Yosemite covered it. However, over a period of time sediment accumulated in the lake, filling it, and the existing valley came into being. “ The Tunnel View is one of the first views of the valley that people see.http://www.shannontech.com/ParkVision/Yosemite/Yosemite.html
Grizzly Giant The height of the tree is 209 feet, circumference is 96.5 feet, and basal diameter is 34.7 feet. It is estimated to be 3,800 years in age. Its looks to be one of the most rugged and ripe tree in the grove of giant sequoias. The sapwood and bark at the base of the tree is 80% consumed over from the fires. The Grizzly Giant was first documented around 1930.
Clothespin Tree The height of the tree is 266 feet tall. The fire burns the tree received has left it with an opening at the trunk which makes it look like a clothespin. The opening of the tree is 70 feet high and 16 feet across.
Faithful Couple The East height of the tree is 248 feet tall and the West height of the tree is also 248 feet tall and the diameter is 19 feet. Many years ago they were two separate trees. Now the bases of the trees are combined together. When the roots of one tree absorbs water it can be nutrition for the other tree too.
Bridalveil Fall The height of the Fall is 620 feet. It is one of the few waterfalls that flow year-round. It keeps flowing because it has a more of a shaded drainage. The Bridalveil Fall was called “Pohono” by the Native Americans.
Mule Deer Mule Deer got its name from their ears that look like mule ears. There ears are flattened to the side when angry, and are laid back against their neck when they are hiding. In late May and early June the fawns are born. The food they mostly eat is leaves, twigs, and buds. Mule Deer Bucks use their antlers for defending themselves and during mating season. The deer protection from enemies is by their running speed.
Half Dome The Half Dome is granite which is igneous rock, and more than 4,737 feet above the valley floor rises the crest. The age of the rock is 93 million years and the Cretaceous period. The dome’s name was at one time “Tis-sa-ack” and it is the name of native women. The face you can see in the dome is known to be her face.
El Capitan The El Capitan is mostly made up of granite, which is igneous rock. The age of the rock is Cretaceous period. Sherwin Glaciation was the main reason for the sculpting of El Capitan, and it lasted about 1.3 million years ago to 1 million years ago. From the base to the peak the granite monolith rises above 3,000 feet.
Yosemite National Park Rock This rock in Yosemite is an igneous rock. I believe it to be granite like the Half Dome and El Capitan. Also I believe it is from the Cretaceous period. Most of the rocks in Yosemite are igneous rocks and referred to as granitic rocks.
References Bridalveil Fall. (n.d.). Retrieved from http://www.world-of- waterfalls.com/yosemite-bridalveil-fall.html El Capitan. (2011, November). Retrieved from http://en.wikipedia.org/wiki/El_Capitan Half Dome. (2011, November). Retrieved from http://en.wikipedia.org/wiki/Half_Dome McFarland, J. (1949). A Guide to the Giant Sequoias of Yosemite National Park. Retrieved from http://www.yosemite.ca.us/library/sequoias_of_yosemite/tour.html The Mule Deer of Yosemite. (2010). Retrieved from http://www.undiscovered-yosemite.com/mule-deer.html Yosemite National Park. (1994-2011). Retrieved from http://www.shannontech.com/ParkVision/Yosemite/Yosemite.html Yosemite National Park. (2011, December). Retrieved from http://en.wikipedia.org/wiki/Yosemite_National_Park