Kategorier: Alla - glaciers - gravity - gradient - drainage

av Rachel Chan för 5 årar sedan

138

rhchan7@gmail.com

Erosion and deposition systems encompass various natural processes that shape the landscape by transporting and depositing materials. Streams or running water are one of the most significant agents of surface erosion, where water flows downhill due to gravity, carrying solids and rocks.

rhchan7@gmail.com

What are the types of erosion-deposition systems?

Glaciers

Ocean Waves

Sediments reach beach by:

Streams (running water)

- Most important agent of surface erosion - Water always flows downhill to lower elevations due to gravity - solid & rock carried with it
river system = a river & all of its tributaries

drainage basin/watershed = all the land that drains into the river either directly or through its tributes - largest in U.S. --> Mississippi River System

Divide = high point separating drainage basins - Ex: Continental Divide (Rocky Mountain) is major divide in U.S.

"Load" = minerals transported down-stream transported 3 ways: 1. Solution (dissolved) 2. Suspension (floating) 3. bed load (along bottom) roll slide bounce

2 Measurements Used to Describe Ability to Erode Materials: 1. Complete maximum size of particles stream can carry 2. Capacity total amount of sediment stream can carry

Factors That Affect the Complete & Capacity of a Stream? 1. Velocity directly related to competence 2. Discharge directly related to capacity

Velocity = distance water travels in a given amount of time - affected by amount of energy a stream has due to: 1. gradient (slope/steepness) 2. discharge (amt of water) 3. channel (path) size (width & depth) shape of the path (straight, curved) - faster velocity = larger particles carried (greater competence)

**See velocity Tree Map**

Wind

Picks up & transports small sediments ex: sand, silt, clay
Factors affected by: - velocity -faster winds (can carry larger sediments. Increase the rate of erosion) - location - arid (dry) climates along coastlines

Sediments: - pitted - scratched - frosted exhibit ventifaction - (wind-warn flat surfaces are sorted

Features: - sand dunes - gentle slope faces direction wind comes from

Mass Movement

Downhill transportation of sediments caused directly by gravity
Examples: - slow-moving - creeps - slump - fast moving - mud flows - earth-flows - land slides -rock falls

factors affected by: - slope - amount of water in soil - bedrock composition & structure