Chapter 2- Center If The Earth Flashcards
Mars earth Venus and Mercury
Terrestrial planets
Saturn and Jupiter
Gas giant planets
Neptune and Uranus
Outer ice giant planets
Asteroids
Small bodies of rock or metal orbiting the sun.
Planetesimals that were never part of a larger planet
Most occur between Jupiter and mad
Comets
Icy planetesimals that orbit the sun.
When approaching the sun they develop a long coma (tail)
Tail= comprised of evaporating gas and dust and points away from sun
Dirty snowballs
H20 CO2 CH4 NH3
Other volatiles
Organic compounds
Dust
Our atmosphere
Mostly N2 and O2.
- other gases argon, carbon dioxide, neon
- less common hades ( helium, methane and krypton
Atmospheric layers
Troposphere - the lower mixing layer, weather is confined to this layer, temperature decreases upward
Stratosphere- no mixing occurs temp increases upward. Ozone area
Mesosphere- temp decreases upward
Thermosphere- outermost layer, temp increase upward farthest from earth
Earth is comprised of
Iron- 32.1%
Oxygen- 30.1%
Silicon- 15.1%
Magnesium- 13.9%
91.2%
Organic compounds
Carbon- containing compounds
Most are residue from once living creatures
These include wood, pear, liginite, coal and oil.
Earth minerals
Crystal- a single coherent mineral with geometric structure
Grain- an irregularly shaped fragment of a larger Crystal
Minerals- comprise rocks and therefore most of the earth
Glasses
Non crystalline soldiers
Rapid cooling- too fast for Crystal growth.
Rocks
Aggregates of minerals, grains and/or glass
- igneous- cooked from a liquid (melt).
- sedimentary- debris cemented from preexisting Rock grains
- metamorphic- rock altered by pressure and temperature
- rocks may be made of a single mineral
Volatiles
Materials that turn into gas at the surface. H2O CO2 CH4 and SO2
There are four fundamental silicate igneous rock types
Vary by silica (SiO4) to iron and magnesium.
- Felsic- Si rich poor in Fe and Mg, granite: Felsic rock with large grains
- Intermediate
- Mafic- Si poor but Fe and Mg rich, gabbro large grains and basalt small grains
- Ultramafic mostly Fe and mg ex: peridotite: small grains
Earth layers
Crust, |upper, transitional and lower mantle | liquid outer and solid inner cores
The crust
- thickest under mountain ranges thinnest under mid ocean ridges.
- continental crust: Felsic, granitic, low Fe-Mg, to intermediate in composition.
- oceanic crust: Mafic basalt and gabbro, high in Fe and mg.
- overlain by sediments
The mantle
- upper, transitional and lower
- Ultramafic rock peridotite
- solid rock, 2,885 km thick 82% of earths volume
- convection aids tectonic plate motion, lava lamp
The core
-Iron rich sphere with a radius of 3,471 km.
-Outer core is liquid iron nickel and sulfur
- inner circle is solid iron nickel alloy
-
Lithosphere
The outermost 100-150 km of earth
- behaves rigidly as a no flowing material
- compromised of two components: crust and upper mantle
- this is what the tectonic plates are made of
Asthenosphere
- upper mantle below the lithosphere
- shallow under oceanic lithosphere; deeper under continental
- flows as a “soft” solid (ductile, malleable, capable of being easily deformed)
One AU
Astronomical unit, the distance between the earth and the sun 93 million miles
