Destructive Processes Flashcards
How does the Earth System function?
By remaining in equilibrium in the constructive and destructive processes
What are the major processes?
Constructive and Destructive
What’s a heat engine?
An engine is that converts thermal energy into useful work
What’s an engine?
A machine with moving parts that converts power into motion.
What’s the difference in terrain development?
The amount of moisture in the terrains
What’s weathering?
The breakdown or rocks and minerals through contact with the Earth’s atmosphere.
Where does weathering occur?
in Situ with “no movement”
What’s erosion?
The transportation or movement of rock materials by agents such as water, ice, wind, and gravity.
What’s the relationship between constructive and destructive processes?
Constructive processes have an internal heat engine and creates or builds new land. Destructive processes have an external heat engine and tears down or destroys land.
What’s the difference between weathering and erosion?
Weathering does not involve movement or transportation but erosion does
What’s mechanical weathering?
The disintegration of rocks or minerals through direct contact with atmospheric conditions, such as heat, water, ice, pressure, and biological agents
What’s another name for mechanical weathering?
Physical weathering
What’s chemical weathering?
The decomposition (decay) of rock or minerals resulting in chemical changes through the direct effects of atmospheric or biological chemicals.
What’s a joint?
A fracture or break in a rock where there has been no movemen`t in the plane of the fracture
How is a joint different than a fault?
A joint haves no movement in the plane of the fracture but a fault does.
What’s the difference between disintegration and decay (decomposition)?
Disintegration is the process of losing cohesion or strength. Decomposition is the state or process of rotting or decay.
What’s the influence of joints on weathering?
They form free space in rocks by which other agents of chemical or physical weathering can enter
What’s root wedging?
Is where plant roots can extend into fractures and grow, causing expansion of the fracture
Which type of weathering does root wedging occur?
Mechanical
How do joints form?
As a result of expanison due to cooling or relief of pressure as overlying rocks are removed by erosion
What are exfoliation (sheeting)?
A type of rock weathering where the rock’s layers peel off in whole sheets instead of grain by grain
What are the types of mechanical weathering?
Ice wedging, thermal stress, exfoliation, salt, and abrasion
What’s ice wedging?
The increase in volume of the water and as the water freezes it expands and exerts a force on its surroundings.
What’s a talus cone?
Scree debris formed to make a scree slope
How is a talus cone formed?
By the dry accumulation of loose scree material
What’s a felsenmeer?
An exposed rock surface that have been quickly broken up by most frost action so that much rock is buried under a cover of angular shattered boulders.
What’s thermal stress?
Is the expansion and contraction of rock due to daily temperature changes or fires. Is effective in deserts or fires.
What’s salt weathering?
The result of physical disintegration of rocks or minerals due to the growth and expansion of various salt crystals that confine to the pores and fissures of rocks or clasts.
What’s biological activity?
Where living organisms contribute to the weathering process in many ways.
What’s the importance of mechanical weathering?
To increase the surface area of rock exposed to chemical weathering
Why is increased surface area of a rock or mineral important?
Because more weathering will occur resulting in a direct relationship, moves more rapidly, and chemical change
What is the importance of physical weathering for increasing surface area?
To allow chemical weathering to increase
What’s the difference between mechanical and chemical weathering?
Mechanical weathering involves physically breaking rocks into fragments without changing the chemical make-up.
Chemical weathering involves a chemical change in at least some of the minerals within a rock.
Why is water such an effective chemical-weathering agent?
Water is a polar molecule, releases H+ ions, is abundant, and carries chemically active ions that attach rock constituents
What’s a polar molecule?
A molecule that can get drawn into rocks that form weak bonds with unsatisfied ones
What do polar molecules move?
By capilarity
What’s oxidation?
The breakdown of rock by oxygen and water, often giving iron-rich rocks a rusty-colored weathered surface.
What’s a weathering rind?
A discolored, chemically altered, outer zone or later of a discrete rock fragment formed by the processes of weathering.
What’s carbonation?
Is the mixing of water with carbon dioxide to make carbonic acid and makes rocks dissolve
What’s the poly-atomic statement of carbonate calcite?
CaCO3
What are the effects of hydration plus oxygen?
Acidic solutions transform feldspar to clays and dissolves carbonates
What are the roles of carbon dioxide in weathering?
It forms carbonic acid which produces calcium carbonate or limestone
What’s hydrolysis?
Where acid rain reacts with rock-forming minerals such as feldspar to produce clay and salts that are removed in solution. Attack by water breakdowns ions -H+
How do everyday chemical agents, like water, oxygen, and carbon dioxide, cause rocks (and our creations) to decompose?
Through oxidation, carbonation, hydration, hydrolysis, and organic acids
What are the types of chemical weathering.
Through oxidation, carbonation, hydration, hydrolysis, and organic acids
What is a soil?
A natural layered mixture of abiotic and biotic material, plus air and water, that forms the interface between the lithosphere and atmosphere
what’s a regolith?
A layer of loose, heterogeneous material covering solid rock and lacks substantial organic matter
What is the formation of soil?
ground state -> A horizon -> B horizon
-> C horizon (Soil)
What does the ground state carry?
Organic matter
Is iron being carried up from the soil or down to the soil?
Down
How does weathering effect soils?
The rocks and minerals are broken down to form soils and give soils its’ texture
Differential weathering (why do different substances weather differently)
The mineral and structure of a rock affects its’ susceptibility to weathering., solubility, planes of weakness, rainfall, temperature
What’s the relationship with spheroidal weathering and joints?
The results in the formation of concentric or spherical layers of highly decayed rock with weathered bedrock that’s known as saprolite.
What are the steps for spheroidal weathering and joints?
- Joints erode
- water penetrates the rock
- The fragments that are left will be weathered forming onion-like weathering
How is soil related to weathering?
Different rocks and minerals affect the different types of soils
How is weathering the key to life?
It releases nutrients and minerals to the soil and allow new rocks to form due to the rock cycle.
How do streams erode or transport Earth materials?
Through abrasion, hydraulicaction, and solution. Hydrologic cycle
What are the types of stream erosion?
Downcutting, lateral erosion, and headward erosion.
What is it called when sediments are deposited by a stream?
Alluvium
Name two areas where off stream deposition occurs?
Floodplain and delta
Where are deltas found?
Where a stream enters a standing body of water
How does a stream transport sediments?
Through a bedload, suspended load, and dissolved load
From where do streams derive their energy?
A slope
What are the agents of erosion?
Streams, groundwater, wind, mass movement, glaciers, waves and tides
What are the three task the agents of erosion perform?
Erosion, transport, and deposit
How much of the Earth’s surface is covered with water?
70%
How much of Earth’s water is in the oceans?
96.5%
How much water does the Earth contain?
less than 1%
How long would Earth’s water be if we can fit it in a spherical bubble?
860 miles in diameter
What’s the hydrologic cycle?
The continuous cyclic movement of water on, above, and below the Earth’s surface.
Which of the agents of erosion is indirectly influenced in the hydrologic cycle?
Wind and mass movement
What is the equation to determine the potential energy in waves?
M * g* h
Where is the low and high discharge located on a slope?
The low discharge is located on top of the slope and the high discharge is located at the bottom of the slope
What’s the longitudinal profile?
Is a diagram of how streams get it’s energy. Slope, headwater, and mouth
What does discharge describe?
How much water is being deposited
Is there high or low discharge if the gradient is low?
high
Gradient is used to define what?
The slope that allows a lot of water to go through
What’s Abrasion?
Where streams carry material in it’s bed, break down rocks, and transport it
What’s a bed load?
Clasts that bounce or roll along the stream bed
What’s a suspended load?
Very fine grains (clay or silt) that mix with the water and don’t sink back to the river bed
What’s a dissolved load?
Ions in a solution
How are suspended loads carried?
Through muddy streams in turbulent water and motion
How are dissolved loads carried?
Through streams that contain chemical solutions and may end up in the ocean
How are bed loads carried?
On the stream bed by traction (rolling, sliding, dragging, or bounding (saltation))
What’s a floodplain?
The drop of loads on adjacent areas
When does a stream lose it’s energy?
When it hits the flat area (low gradient)
What’s hydraulic actions?
The force and pressure of water that breaks up bug boulders of rocks and transport them
What’s solution?
Where rocks are dissolved by the slightly acidic water of streams then the sediments are feed and transported
What’s lateral cutting?
Streams cutting in the floodplain horizontally to slow down itself
What’s headward cutting?
Streams cutting in the floodplain vertically to slow down itself
What’s down cutting?
When it rains an area fills with water and move the boulders down
What’s alluvium?
Sediments deposited by a stream
What’s a delta?
Layers of sediments that are dropped at the mouth of the river
What are levees and what are they used for?
A natural or artificial wall that blocks water from going where we don’t want it to go
What’s the base level of a stream?
The lowest points to which it can flow, often referred as the mouth of the river
What’s a runoff?
Movement of water over land via streams
What’s a headwater?
Place where streams start
What’s an example of a headwater?
A V-shaped stream valley
What’s a stream?
Any body of running water confined to a channel, often starting in mountains and ending at the sea
What’s a drainage basin?
The total area of land drained by a stream and all of its branches or tributaries/ feeders
What’s another word for drainage basin?
Watershed
What’s a stream meandering?
A stream that is sinuous and develop in areas with low gradients. (Have a lot of curves)
What are the hazards with loving along a stream?
Floods
