Ch 6. Geomorphic Processes - Exogenic and Endogenic Processes Flashcards
What is Gradation ?
The wearing down of relief features is called Gradation
What is a Geomorphic process ?
Geomorphical processes - Natural erosion, weathering and depositional mechanisms. They result in the alteration of the earth’s surface materials and landforms
What are exogenic geomorphic processes ?
Processes that act on the surface of the earth.
Weatheing, mass wasting, deposition and erosion are called exogenic geomorphic processes
What are endogenic geomorphic processes ?
Geomorphic processes that act in the earth’s interior.
Volcanism and diastrophism are endogenic geomorphic processes
What is a geomorphic agent ?
Any exogenic element of nature such as water, wind and ice; that is capable of collecting and carrying earth materials is called as geomorphic agent
What is Diastrophism ?
All processes that involve elevating, moving or building up components of the earth’s crust are called Diastrophism (slow movement)
What are Orogenic processes ?
Endogenic processes which lead to mountain building by the way of folding
What are Epeirogenic processes ?
Endogenic processes which lead to Continent building
What is Weathering ?
The breaking of rocks on the earth’s surface by different agents like rivers, wind, sea waves and glaciers
What is Erosion ?
The carrying of broken rocks from one place to another by natural agents like wind, water and glaciers
What is Mass movement ?
Mass movements are defined as processes of transport and accumulation of material that occur on both gentle and steep slopes mainly owing to gravitational forces. Mass movement is a subset of Erosion
What is the difference between Geomorphic processes and agents ?
Geomorphic process is a force applied on the earth materials affecting the same. While geomorphic agent is a mobile medium (like running water, moving ice masses, the waves and currents, wind, etc.) that weathers, erodes and deposits earth materials
How is Physical / Mechanical Weathering caused ?
- Gravitation force
- Water pressure
- Expansion forces
- Freezing, thawing and frost wedging
- Salt weathering
What is a Tor ?
A smoothly surfaced and rounded boulder formed due to exfoliation
How is Chemical Weathering caused ?
- Solution
- Carbonation
- Hydration
- Oxidation
- Reduction
What is Biological Weathering ?
Removal or contribution of minerals to the environment due to biological activity is called Biological Weathering
What is a Creep (Mass movement) ?
It occurs on moderate, steep, soil-covered slopes. It dosen’t need to be lubricated with water like in soliflucation
Under this, the movement is extremely slow and less visible except when it is observed over the long period of time
What is Solifluction
It is the process of slow flowing of soil mass or fine-grained rock debris downslope which is saturated or lubricated with water
It can be considered as a type of creep where lubricated water influences the soil movement. It primarly occurs in permafrost region
What is a Mudflow ?
With heavy rainfall and in the absence of vegetation cover, huge amount of soil and other material get saturated with water and either slow or rapidly flow down along definite channels is called as mudflow
What is an Earthflow ?
Movement of water-saturated clayey or silty earth materials downward through low angle terraces or hillslides is called earthflow
What is an Avalanche ?
An Avalanche is a type of landslide that occurs in snowy regions
What is a Landslide ?
A Landslide is a form of mass wasting that includes the movement of a large area of land under the force of gravity. It is made of soil, rocks or mud
What is a Slump ?
a landslide consisting of a mass of material moving downslope as a unit, usually along a curved plane of failure.
What is Abrasion ?
Abrasion is a process of erosion which occurs when material being transported wears away at a surface over time. It is the process of friction caused by scuffing, scratching, wearing down, marring and rubbing away of materials
What are different events in Erosion ?
Detachment, entrainment and transportation
What is Entrainment in Erosion ?
entrainment is the process by which surface sediment is incorporated into a fluid flow (such as air, water or even ice) as part of the operation of erosion.
What is Suspension in Erosion ?
Suspension is where, without coming in contact of their origin, the particles are held by the medium
What is Saltation in Erosion ?
Saltation is where the particle travels in fast, repetitive cycles from the surface to the medium. Usually the action of returning to the surface has enough force to allow new particles to be entrained
What is Traction in Erosion ?
It is the displacement of the particles around the eroded surface by rolling, slipping and shuffling
What is Flocculation in Deposition ?
It is chemical process in which salt allows minute claly particles to be aggregated into larger masses which are too heavy to remain suspended
Which factors are responsible for soil formation ?
- Parent material
- Climate
- Precipitation
- Temperature
- Biota
- Topography
- Time
