4.E.2.3: Give examples of how the surface of the Earth changes due to slow processes such as erosion and weathering, rapid processes such as landslides, volcanic eruptions, and earthquakes.

The Earth is Constantly Changing

Slow Changes Erosion Weathering Deposition Examples: Canyons,

valleys, caves, deltas, mushroom rocks and rock arches

Rapid Changes Results of a natural

disaster. Examples: landslides,

volcanic eruptions, floods, tsunamis

Slow Changes

FOUR MAIN THINGS CAUSE SLOW CHANGES:

1. Water2. Wind3. Plants4. Ice

A change to Earth’s surface that takes a very

long time

Water: Deltas

Water can slowly carry sediments of weathered rock and deposit those pieces to a new location (deposition)

This process makes DELTAS.

These are formed at the mouth of rivers.

Water: Canyons

Canyons are formed when a river cuts through rock over a very long time.

The river slowly weathers and erodes the rock.

Weathering and Erosion by Wind : Mountains Become Flat

Over time, a mountain can flatten.Weathering and erosion slowly changes the

shape of a mountain.

Wind: Rock Arches and Hoodoos

Wind can carry weathered rock.

When the little pieces hit rock, it can form unique shapes.

The wind acts as a sandblaster, slowly shaping the rock into formations like a rock arch and a hoodoo.

Ice: U-Shaped Valleys

The movement of ice from a glacier can weather and erode rock.

When the glacier melts, a U-Shaped Valley will be left.

Ice: Weathering

Ice can also break rock apart.

Water seeps into the cracks of rock. When the water freezes, the rock breaks apart.

Plants: Weathering

Plants can grow into the cracks of rocks and cause weathering.

As the plant gets bigger and bigger, the rock gives way and cracks.

Rapid Changes

Volcanic eruptionsLandslidesEarthquakesTsunamisChanges to Earth’s

surface that occurs over a short period of time. Usually the result of a

natural disaster.

Tectonic Plates

The Earth is divided into separate sections called tectonic plates.

These plates move very slowly

The plates can move side by side, away from each other or toward each other

During the movement, some natural disasters may occur.

Earthquakes

The result of a sudden release of energy from the movement of plates.

They can cause cracks in the ground and fault valleys may form.

Streams/rivers may change paths.

Volcanic Eruptions

The movement of plates can cause volcanoes to erupt.

When a volcano erupts, the surface of the Earth changes.

New land can form, vegetation in the lava path can be destroyed

Landslides

The mass movement of rock, debris, and soil down a slope of land

Can be caused by heavy rainfall, earthquakes, overdevelopment and deforestation.

Tsunamis

A series of enormous waves created by an underwater disturbance.

Usually associated with earthquakes occurring below or near the ocean.

Volcanic eruptions, submarine landslides, and coastal rock falls can also generate a tsunami.

Review1.What are the slow changes to Earth’s surface?2.What are the rapid changes to Earth’s

surface?3.What are the cause and effects of an

earthquake?4.What are the cause and effects of a landslide?5.What are the cause and effects of a tsunami6.What are the cause and effects of a volcanic

eruption?