What is Weathering, Erosion and Deposition??

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What is Weathering, Erosion and Deposition??
Winds sweeping through the Grand Canyon have
eroded this sandstone outcrop into an anvil
shape. Wind shapes these fantastical forms by
eroding less dense rock, like sandstone, faster
than surrounding rock.
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Weathering and Erosion
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A thunderstorm does its part to shape Utah's
Mussentuchit Badlands. Although this area gets
only scant rainfall, over centuries,
precipitation and wind have taken turns creating
this rugged land's hundreds of gullies, ravines,
and washes.
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A waterfall fed by glacial runoff tumbles over
sheer cliffs and into the turquoise water of
Admiralty Inlet on Baffin Island, Nunavut,
Canada. Such moving water is among the most
powerful of nature's landscape-altering tools
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Sandbars swirl beneath Oregon Inlet in Cape
Hatteras National Seashore on North Carolina's
Outer Banks. Waves driven by ocean winds can
cause the sandbars here to shift and change
literally by the hour, making conditions
hazardous for boats.
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The Mississippi River Delta is the modern area of
land (the river delta) built up by sand deposited
by the Mississippi River as it slows down and
enters the Gulf of Mexico. The deltaic process
has, over the past 5,000 years, caused the
coastline of south Louisiana to advance gulfward
from 15 to 50 miles (24 to 80 km).
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With the snow-draped Sierra Nevada as a backdrop,
unique erosion formations called sand tufa
stand like giant cauliflower stalks in a dry
Arizona lake bed. Before this alkaline lake went
dry, tufa formed when a freshwater spring
percolated from below and formed calcium
carbonate deposits. When the lake's level
dropped, these fragile formations surfaced, and
wind went to work removing the sand beneath the
deposits.
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Persistent winds in the mountains of Nevada's
Great Basin National Park eroded the trunk of
this old pine tree into what look like a pair of
sideways spectacles. The Great Basin hosts
drastically varied climates, from its cold, snowy
mountains to its dry, hot desert valley.
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The Bernard Glacier in Alaska's Saint Elias
Mountains looks like a huge alpine highway.
Glaciers are slow but highly effective shapers of
the land, essentially carrying away anything in
their pathfrom soil and rocks to hills and even
the sides of mountains.
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Heavy rains in northwest Iowa washed away soil,
leaving this scarred tableau. This type of
erosion, termed sheet-and-rill erosion, occurs
when there is insufficient vegetation to hold
soil in place. As rain falls, it forms sheets of
surface water that transport soil away. As more
water accumulates, it forms runoff channels
called rills, which further displace soil.