EARTH´S SYSTEM Flashcards
- Any portion of the universe that can be isolated from the rest of the universe for the purpose of observing and measuring changes.
- Each system of the earth interacts with one another that allows it to support life.
System
A self- contained system (in which the boundary permits the exchange of energy, but not matter, with surroundings).
Closed System
Energy and matter flow in and out of the system.
Open System
The earth after its formation, differentiated into: crust, mantle, and core
Geosphere
- The process that created the earth´s layered structure
- the denser material sinks to the center )forming the core)
- the less denser amterial floated to the top forming the crust.
Planetary Differentiation
The thinnest layer rangign from 5 to 80 km thick and occupies greater than 1% of the Earth´s volume.
Crust
What is the two types of crust?
- Oceanic crust
2. Continental crust
- mostly composed of granitic rocks
- thicker with an average thickness of 35 km
- less dense (2.7 g/cm3
- older (some are 4 billion years old)
Continental Crust
- mostly composed of basaltic rocks
- the denser and thinner crust (3.0 g/cm3)
- roughly 7 km thick
Younger (180 million years old or less)
Oceanic Crust
The thickest layer occupying 83% of the Earth´s volume
Mantle
The boundary between the crust and the mantle which was named after the seismologist, Andrija Mohorovicic.
Mohorovicic Discontinuity
How thick is the mantle?
2900 km thick
What´s the estimated temperature of the mantle
1000 celcius to 3700 celcius
What is the top part of the mantle primarliy composed of?
Peridotite (rock)— made up of olivine (Mg, Fe)2 SiO4
The composition is thought to be the most iron and nickel with some oxygen, sulfur, and silicon.
Core
This refers to the boundary between the mantle and the core named after the seismologist Beno Gutenburg.
Gutenburg Discontinuity
This is the denset portion of the Earth with an average density of 11g/cm^3 to nearly 14 the times the density of water.
Core
This is defined based on the mechanical properties and is observed using the behavior of seismic waves as it travels through the interior of the earth.
Layeing by Physical or Mechanical properties
- primary wave
- passes thorugh solid and liquid
P Wave
- Shear Wave
- Does not pass through liquid
S Wave
This is the upper mantle + the crust. This is also relatively rigid and is known to break due to stress and the site of most earthquakes.
Litosphere
This is what you call the litosphere when its broken down into large fragments
Litospheric Plates
¨Weak¨(asthenos) sphere which lies below the litosphere from ~100 km until a depth of 660 km. Also, the litosphere floats above this layer and convection is also thought to occur here.
Asthenosphere
Due to the small amounts of melting present, it flows like the flow of honey, being very slow.
Ductile Behavior
