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最近又一次参观大峡谷(Grand Canyon, AZ, USA), 与诸位分享以下它的雄伟与壮观. 如果你喜欢地质, Grand Canyon should be added to your visiting list. 约6百万年前Colorado River 冲刷,切割地层 (每年切割约一张纸的厚度)逐渐形成了现在的大峡谷. Teddy Roosevelt 罗瑟福总统曾说 “Keep it…as the one great sight which every American…should see.” 我建议每个地质学(及爱好)者应该参观大峡谷.
傍晚的大峡谷.
傍晚的大峡谷:五彩缤纷的岩层.
一石二鸟 or 二鸟戏石?
在大峡谷留影.
坚硬的石灰岩形成陡峭的悬崖, 而页岩则相反.
中午的大峡谷
The geology of the Grand Canyon area exposes one of the most complete and studied sequences of rock on Earth. The nearly 40 major sedimentary rock layers exposed in the Grand Canyon and in the Grand Canyon National Park area range in age from about 200 million to nearly 2 billion years old. Uplift of the region started about 75 million years ago during the Laramide orogeny; a mountain-building event that is largely responsible for creating the Rocky Mountains to the east. In total the Colorado Plateau was uplifted an estimated 3.2 km. The adjacent Basin and Range province to the west started to form about 18 million years ago as the result of crustal stretching. A drainage system that flowed through what is today the eastern Grand Canyon emptied into the now lower Basin and Range province. Opening of the Gulf of California around 6 million years ago enabled a large river to cut its way northeast from the gulf. The new river captured the older drainage to form the ancestral Colorado River, which in turn started to form the Grand Canyon.
Bonus/附: Hole in the rock in Phoenix.
洞月争辉 (in Phoenix, AZ)
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