Slow Changes to
Earth’s Surface
Weathering, Erosion, and Deposition
from Ice, Water, and Wind
Weathering, Erosion, and Deposition
• Weathering? • Weathering is the breaking
down and wearing away of
rock.
• Erosion?
• Erosion is the movement of the
weathered materials by ice,
water, or wind.
• Deposition?
• Deposition is the dropping off or
depositing of the materials that
were eroded by ice, water, and
wind.
Weathering, Erosion, and Deposition by Ice
U-Valley Formation by a Glacier
Glaciers: U-Shaped Valleys
Glaciers: Fjords
Weathering, Erosion, and Deposition
by Ice Formation of Fjords
• Fjords are created when glaciers retreat.
• The glaciers weather and erode the land, forming
the U-shaped valley.
• The material is deposited in various locations in the
valley.
• When the glacier retreats and sea levels rise, the
water flows into (and fills) the valley floor.
Weathering, Erosion, and
Deposition by Water: Canyons
Weathering, Erosion, and
Deposition by Water: Caves
Weathering, Erosion, and Deposition
by Water: Caves
• Caves can be formed by many processes, but erosion
by water is one of the more common ways.
• In Texas, we have many limestone caves. Water
enters the caves and weathers the rock by dissolving
the limestone.
• When water levels rise, the minerals are carried away.
• Calcium carbonate is deposited when water
precipitates through the limestone.
Weathering, Erosion, and
Deposition by Water: Delta
Weathering, Erosion, and
Deposition by Water: Delta
• A river delta forms at the mouth of a river.
• The flowing river has weathered and eroded the river
bank and the river floor, carrying the sediment in the
moving water.
• The sediment, that has been carried by the river, is
deposited as the river flows into an ocean, sea, or
estuary.
Weathering, Erosion, and
Deposition by Wind: Sand Dunes
Weathering, Erosion, and
Deposition by Wind: Sand Dunes
• A sand dune can form
from the movement of
water or wind.
Wind direction
• Most sand dunes have
one side that is steeper
than the other.
Movement of the sand dune
Weathering and Erosion by Wind:
Hoodoos Pinnacles
Weathering and Erosion by Wind :
Rock Arches
Weathering and Erosion by Wind :
Rock Arches
1. Deep cracks form in sandstone. (Remember your observations of
the frozen rock?)
2. Erosion wears away the exposed rock layers.
3. Water may enter the cracks, freeze, and widen the cracks further.
Wind also wears away the rock particles.
4. Weathering and erosion continues until an arch, or bridge, remains.
Over time, with continued weathering and erosion, the arches will
collapse.
Weathering and Erosion by Wind
Weathering, Erosion, and Deposition by
Wind and Water: Beaches
Weathering, Erosion, and Deposition by
Wind and Water: Beaches
• Beaches are the result of wave action.
• Waves or currents move the sand (or other sediments along
the shore).
• Initially, the sediments on the beach were weathered and
eroded from rock.
• Wind carried the sediment, and it is deposited either on the
land or in the water.
• Sediment that is suspended in the water is carried in the water
by ocean currents and eventually, may be deposited on the
shore by waves.
• The waves both deposit sand from the ocean bed and erode
sand as the water pulls back into the ocean.
Weathering, Erosion, and Deposition by
Wind and Water: Barrier Islands
Weathering, Erosion, and Deposition by
Wind and Water: Sea Caves