The manner in which the Sierra Nevada mountains formed in California — from the uplift of the Pacific plate driving beneath the North American plate — brought gold and silver closer to the surface through heated veins in the rock beneath the ground.
Erosion from weather exposed these veins on the sides of mountains, and the malleable gold washed down into the waiting rivers below. The gold beneath these landforms eventually played a role in California becoming a state in As a journalist and editor for several years, Laurie Brenner has covered many topics in her writings, but science is one of her first loves.
Her stint as Manager of the California State Mining and Mineral Museum in California's gold country served to deepen her interest in science which she now fulfills by writing for online science websites. Brenner is also a published sci-fi author.
She graduated from San Diego's Coleman College in Related Articles Landforms Near Chicago. Where to Rock Hunt Gems in Idaho. This combined with cooler temperatures at night can result in valley fog and clouds. Strong wind events can occur in a valley. It tends to keep higher elevations relatively warmer while the valleys become much colder. Additionally, cool air on the hills will fall into the neighboring valleys because it is more dense than the surrounding warm air.
They are packed more tightly together. As the ground begins to radiate heat into the atmosphere, the air temperature cools and the colder, more dense air slides down the mountain slopes into the valley below. Temperature extremes are a characteristic of most deserts. In some deserts, temperatures rise so high that people are at risk of dehydration and even death. At night, these areas cool quickly because they lack the insulation provided by humidity and clouds. Not all deserts get cold during the night.
The air in dry areas cools off when there are no clouds covering the area, when there is no wind or, naturally, when there is almost no moisture in the air. Because deserts have such little water vapor in the air, it makes it harder to trap heat or cold in a desert. Because of this, some deserts can get cold at night, dropping to below 40F, which is definitely coat weather. How can the desert be so hot during the day and yet get so cold at night?
The deserts of the southwestern United States tend to be relatively cloud-free, and the lack of clouds that allows the sun to beat down mercilessly during the day also allows the rapid loss of heat energy back into the sky at night. More importantly, they protect against solar radiation that causes sunburn and increases body temperature, and trap more cool air next to the skin. Actively scan device characteristics for identification.
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Geography Expert. The bulk of the rock and dirt is dredged from the bottom of the channel, a process called down cutting that can ultimately lead to deep, slender chasms like Black Canyon in Colorado's Gunnison National Park. Some river and stream valleys, especially those in the mountains or located near the North and South Poles, are transformed by glaciers. The massive blocks of snow and ice slowly creep downhill where they will meet the least resistance: valleys already cut by rivers and streams.
As the glaciers ooze, they pick up rocks and grind away at the valley floor and sides, pressing the "V" into a "U. Side valleys are formed by tributaries to streams and rivers and feed the main stem. Where the main channel is carved deeper than the tributary, as commonly occurs during glaciations, the side valleys are left hanging.
Waterfalls often cascade from the outlet of the upper valley into the drainage below. Hollows, like those in Appalachia , are small valleys nestled between mountains or hills. The red of cactus blooms pops in a Grand Canyon valley.
Cut by the Colorado River over millions of years, the Grand Canyon is considered one of the finest examples of arid-land erosion in the world. The immense canyon is miles kilometers long and averages 4, feet 1, meters deep, but it is only 15 miles 24 kilometers across at its widest.
Giant valleys, called rifts, are found where two pieces of Earth's crust are separated or split apart. All rights reserved.
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