Weathering, Erosion And Deposition Flashcards
Chemical weathering
- Changes the kind of material.
- reactions occur on the surface
- water is required
- hotter=faster
- fastest chemical weathering occurs in warm/moist climates
Weathering
The breaking up of rock from large particles to smaller particles.
A.) this increases surface area of the rock which speeds the rate of chemical weathering
Oxidation
When iron combines with oxygen to make rust.
Hydration
Minerals in rocks combine with water.
Carbonation
When rocks react with carbonic acid.
Frost action
Water gets into cracks- freezes - expands - enlarges the crack. Requires alternating freeze-thaw cycles
Wave action
Waves pounding against rocks- sand and rocks in the waves help to break up the shorline
Stream abrasion
The rounding and smoothing of rocks as they tumble in a stream. The rocks downcut the steams V-shaped channel as they roll along
Wind abrasion
Important in dry climates. The wind picks up sand and blows it against rocks causing pitting. (Sandblasted appearance)
Root wedging
Plant roots grow into cracks In rock and split them
Physical weathering
The breakdown of rock into smaller pieces without a chemical change.
Erosion
Process where particles are transported as sediment.
Agents of erosion.
Forces that are set in motion by gravity that causes sediments to move.
Examples of Agents of Erosion
- streams
- waves
- glaciers
- wind
- mass movement
Gravity
Direct role
•force behind most agents of erosion
•causes rivers to flow, ice to move, and rocks to slide.
The sun
Indirect role
•drives the water cycle which produces rain and ice
•fuels winds and drives ocean currents
Deposition
Process by which sediments are released from an erosional system
Size of sediments
Larger sediments will settle faster
Shape of sediments
Rounder sediments settle faster and flatter sediments will take longer
Density of sediments
More sense sediment will settle faster
Sorted sediment
Layers of sediment that are similar in size, shape or density.
Ex: deposition from a steam
Unsorted sediment
Layers of sediment that are mixed in size, shape or density.
Ex: deposition from a glacier
Abrasion
Occurs when rock particles grind against rock.
Infiltration
The process which water goes into soil or rock
Porosity
Amount of pour space in soil.
Humus
Part of soil that serves as a source of plant nutrients
Capillarity
Water stored in small openings from the zone of saturation
Permeability
To allow Fluids to pass through soils
Impermeable
Not allow fluids to pass through
Glacial grooves
Long parallel scratches formed by sediment embedded in a glacier that has passed over the surface
Kettle lake
Depression left in the ground that is filled with glacial melt water
Outwash plain
Broad glacial feature of smaller sediment carried from melting water of a retreating glacier l
Deflation
Wind blows away loose sediment lowering the land surface until there is no more lose sediment to erode
Horizontal sorting
When the velocity of wind or water decreases the size roundness and density decrease as u move farther out
Vertical sorting
Larger or more dense sediments settle to the bottom. Followed by decreasing size and density
Continental glacier
Huge sheets of ice that cover entire land masses
Valley glacier
Glaciers that form in high elevations in mountain valleys
U-shaped valleys
Shape of the valley walls from glacial erosion
Erratics
Large deposited fragments that can be transported hundreds of miles inside or on top of the glacier
Drumlins
Streamlined oval shaped mounds of Unsorted sediment
Eskers
A long winding ridge of Sand and gravel
Terminal moraines
A mound of till deposited along the leading edge of a glacier
Windward side has what kind of slope?
Gentle slope
Leeward side has what kind of slope?
Steep slope
Long shore current
Ocean current that flows parallel and close to the shore
Mass movement
The pulling of rock and sediment downhill by the force of gravity
