True or False: The Earth’s surface has stayed the same for thousands of years
True or False: The Earth’s surfacehas stayed the same for thousands of years The Earth’s surface is always changing!
WeatheringThe breakdown do the materials of Earth’s crust into smaller pieces.
Water causes weathering What evidence ofweathering do you see in this picture?
Wind causes weatheringWhy wasn’t this mass of land weathered away? What evidence of weathering do you see in this picture?
Ice causes weathering Describe how icecauses weathering?
Erosion The process by which water, ice, wind or gravity moves fragments of rock and soil. What evidence oferosion do you see in this picture?
Erosion is Movement of Sediment!• This process, known as Erosion, is gradually wearing down the surface of the earth.• Erosion is the process by which weathered rock and soil (sediment) are moved from one place to another. • Erosion carves the Earths surface creating What do you think has caused canyons, gorges, and this rock to look this way? even beaches.
Wind Erosion• As the wind blows it picks up small particles of sand/sediment and blasts large rocks with the abrasive particles, cutting and shaping the rock.• The intensity of wind erosion is determined by: • Sum (amount) • Speed • Slope • Surface
Water Causes Erosion• runoff, rivers and, streams
Water causes ErosionWhen rain falls to the Earth it can evaporate, sink into the ground, or flow over the land as Runoff.When it flows over land, erosion occurs.Runoff picks up pieces of rock and "runs" downhill cutting tiny grooves (called rills) into the land.
Water causes Erosion How much erosion takes place is determined by the: • Sum (amount) • Slope • Speed • SurfaceCan you act increasing and decreasing the four S’s?
Ice Causes Erosion Glaciers wear down thelandscape; by picking up and carrying debris that moves across the land along with the ice.
Ice Causes ErosionGlaciers can pick up and carry sediment that ranges in size from sand grains to boulders bigger than houses. Moving like a conveyor belt and a bulldozer, a single glacier can move millions of tons of material!
Ice Causes ErosionHow much erosion takes place is determined by the: • **Sum (Glaciers are massive!) • Slope • Speed • Surface
Gravity causes erosion Creep, Slump, Landslides, Mudslides, and Avalanches.Slower Faster These are examples of mass movement landslide clip.mpeg (or called mass wasting)
Gravity causes ErosionHow much erosion takes place is determined by the: • Sum • **Slope • Speed • **Surface
Deposition Rock particles that are picked up and transported during erosion will ultimately be deposited somewhere elseDeposition is the process by which sediments (small particles of rock) are laid down in new locations. • Together, Erosion and Deposition build new landforms. • Deltas • Canyons • Meanders • Floodplains
DeltaWhere rivers meet the ocean is called the mouth of the river. Soil and dirt carried by these rivers is deposited at the mouth, and new land is formed. The new, soil-rich land is known as a Delta
Canyons This simple animation provides you with a visualization of how the Colorado River has "downcut" into the rock layers of the Grand Canyon. How long it took to carve the Grand Canyon is debated by geologists. Some estimates are between 6 and 8 Canyons are large million years, which is very recentvalleys created by a river or stream. by comparison.
Meanders Meandering streams wander side to side as they constantly seek out the lowest elevation.This constant motion creates a series of S-shaped “loops”.
MeandersStream Velocity varies from one side to the other side of the “S”, resulting in erosion in some places and deposition of sediments in others.
Floodplains• Floodplains form along the banks of mid-order streams and larger rivers.• These are low-lying areas along the sides of a river channel that have regular times of heavy waterflow to cause the river to spill over and flood the land.