W.E.D.

W =

E =

D =

***Water, Ice, and Wind cause W.E.D.***

These forces are responsible for forming many of the landforms on Earth.

They may be DestructiveorConstructive.

Constructive Force: a force that builds up sediment to create a new land form. – ex. Deposition

Destructive Force: a force that tears down an existing landform and turns it into sediment. – ex. Weathering & Erosion.

So what exactly is sediment? It is broken pieces of rock.

So what makes it different from soil? Soil contains pieces of rock, shell, decaying plants, decaying animals, and animal waste.

**In other words soil is made up of both Inorganic (nonliving) and Organic (living) materials. Rock is not. **

W.E.D. all help create new soil by breaking down rock.

Soil Layers:

Types of Soil

The organic part of soil is called humus. It contains the remains of dead plants and animals and animal waste.

Sand is the largest type of soil particle. It does not hold water well because the larger particles do not pack together. It feels gritty to touch.

Silt is made of smaller particles than sand, and holds water better than sand. It feels smoother than sand but still grainy.

Clay is the smallest soil particle. It holds water well because the tiny particles pack together. If feels clumpy and sticky.

Loam is a mixture of clay, silt, and sand particles in equal parts. It is the best for growing crops because it allows for water and air flow, but holds on to some water and humus also.

Landforms

  1. Mountains- formed by the movement of tectonic plates
  2. Mountains are weathered and eroded by wind and water.
  3. Younger mountains will be very sharp and jagged. Ex.- Rocky Mountains
  4. Older mountains will be smoother and more rounded. Ex.- Appalachian Mountains
  1. Canyons- formed by weathering and erosion
  2. Rivers running over plateaus cause canyons to form.
  3. Ex.- Grand Canyon
  1. Deltas- formed by deposition
  2. As rivers meet lakes or oceans, the water slows.
  3. As the water slows, sediment is dropped at the mouth of the river forming very fertile soil.
  1. Sand dunes- formed by deposition
  2. As wind blows, sediment is dropped to form sand dunes.
  3. As the sediment piles up, the dunes take shape.
  4. Sand dunes are found in deserts and along shorelines.

5. Arches – formed by weathering and erosion

  1. Sea Arches are formed by waves hitting a cliff face and weathering/eroding away a portion of the cliff. It can start as a sea cave that eventually expands through a portion of the cliff or connects with another cave on the opposite wall of the cliff.
  2. Sandstone Arches are formed from weathering/eroding in cracked or weakened areas of sandstone. This creates walls that eventually will develop holes in them that continue to weather and erode forming the arch.

Landforms Continued

6. U-Shaped Valley – formed from weathering and erosion.

  1. Due to glacial movement through the area.
  2. Moving glaciers will scrapes away rock sediments, uproots vegetation, and moves away large boulders.

7. Caves – formed by chemical and physical weathering & erosion.

  1. Sea caves form from waves that enlarge small openings at the base of a cliff over time.
  2. Underground caves result from rain water dissolving CO2 creating a weak acid. This acidic water helps dissolve minerals and enlarges cracks eventually eating away holes in the ground.

-- Minerals dissolved in water drips in the caves form stalactites (formations from the cave ceilings) and stalagmites (formations built up from the cave floor).

Additional Landforms:

Plateau

Hill

Plain

Beach

Mesa

Buttes

Meander

And so many more…………..

Check out these links to learn more: