类别 全部 - landforms - erosion - weathering

作者:Kim McCarrick 13 年以前

1295

Weathering

The natural processes shaping the earth's surface include weathering, erosion, and the formation of various landforms. Weathering involves the breakdown of rocks into smaller pieces through mechanical means, such as physical disintegration without altering the rock'

Weathering

Weathering and Erosion

Erosion

Water
Ground water

Subtopic

Runoff

Young streams

Gradient

V-shaped land

steep at head; flat at mouth

slope of stream

Stream devlopment

Longitudinal Profile-the side view fom head to mouth.

Types depend on shape, speed, volume of water.

stream = any channelized flow of water

Over time, continuos hill erosion leads to the devlopment of a stream

What affects runoff?

Vegetation

Slope of land

The water content of soil

The intensity and duration of rainfall

Mass Movement
Wind
Waves
Glacier
Landforms

Fjord

U-shaped valley filled with water

Kettle lakes

ice melt in own hole

Drumlins

Mounds and hills of tills

Erratics

Large rocks; unrelated placement

Till

Pile of debris left behind; unsorted

Fingerlakes

Giant, long, deep, glacial grooves; makes lakes

Moraines

Medial

In the middle of the glacier

Terminal

Rock and debris at the furthest point the glacier has reached

Dark bands: Rocks

Usualy on the outer edge

Type

Valley or Alpine

small; in between valleys

Continental

Large; spread out like a pancake (flat suface)

Description

Huge rock conveyor belts of ice

Rate of melting = Rate of moving

parallel grooves; scratched and polished

Weathering

Break down of rock over tiime
Mechanical

Organic activity

Roots; animals

Exfoliation and unloading

Rock weathers away

Less weight and pressure

Breaks into sheets and slabs

Frost wedging

water gets in

water frezes, expands

Freeze and thaw cycles

Disintegrates; no change in composition

Physical; into smaller peices

Chemical

Acid reactions

Dissolves

Oxidation

Rust!

More surface area; more weathering