Landforms

Investigation 2 – Steam Tables

Part 1: Erosion

• Vocabulary– Drainage basin – a system of rivers and streams

that drains an area like the Colorado Plateau.– Erosion – involves 2 processes: weathering

(wearing away of earth materials by water, wind or ice) and transport (movement of earth materials to new locations by water, wind or ice).

– Landform – a shape of feature of the earth’s surface, like a delta or canyon.

Part 1: Erosion

• Vocabulary– Canyon – a V-shaped valley eroded by a river or stream.– Delta – a fan-shaped (triangular) deposit of earth

materials at a mouth of a stream.– Plateau – a large, nearly level area that has been lifted

above the surrounding area.• Main Ideas– Water flowing over earth materials may erode them.– Rivers can create landforms called canyons or deltas.

Science Stories

• Real People in the Grand Canyon– It is believed that water erosion over many years

formed the Grand Canyon.– The earliest inhabitants of the GC called

themselves The Desert Culture.– The oldest evidence of humans in the GC is split-

twig figures.– Members of the Havasupai tribe live in the GC

now.

Science Stories

– The Glen Canyon Dam reduced the flow of water and changed the erosion of the Grand Canyon and he habitats of the organisms that live there.

– Today, artificial floods are created by releasing water from the Glen Canyon Dam to restore natural conditions in the GC.

Part 2: Deposition

• Vocabulary– Deposition – the process by which eroded earth

materials settle out in another place.– Sediments – eroded earth materials that have been

deposited.– Basin – a low area in which sediments are often

deposited.– Channel – the course of path the water takes in a

stream or river.– Meander – a curve or loop in a channel.

Part 2: Deposition

• Main Ideas– Earth materials eroded by rivers are deposited as

sediments.– Heavier earth materials like sand are deposited

before lighter materials like clay.– Water in a river follows the lowest channel.– The Colorado River might have eroded the earth

materials that make up the Colorado Plateau.