Earth's outer core

outer corecoreEarth's coreouterouter core of the Earthcore of the EarthEarth's outerliquid coremolten coreplanetary core
Earth's outer core is a fluid layer about 2400 km thick and composed of mostly iron and nickel that lies above Earth's solid inner core and below its mantle.wikipedia
78 Related Articles

Iron

FeFe 2+ Fe(III)
Earth's outer core is a fluid layer about 2400 km thick and composed of mostly iron and nickel that lies above Earth's solid inner core and below its mantle.
It is by mass the most common element on Earth, forming much of Earth's outer and inner core.

Nickel

NiNi 2+ Nickel (Ni)
Earth's outer core is a fluid layer about 2400 km thick and composed of mostly iron and nickel that lies above Earth's solid inner core and below its mantle.
An iron–nickel mixture is thought to compose Earth's outer and inner cores.

Earth's inner core

inner coreEarth's corecenter of the Earth
Earth's outer core is a fluid layer about 2400 km thick and composed of mostly iron and nickel that lies above Earth's solid inner core and below its mantle.
The Earth was discovered to have a solid inner core distinct from its molten outer core in 1936, by the Danish seismologist Inge Lehmann, who deduced its presence by studying seismograms from earthquakes in New Zealand.

Mantle (geology)

mantleEarth's mantlemantles
Earth's outer core is a fluid layer about 2400 km thick and composed of mostly iron and nickel that lies above Earth's solid inner core and below its mantle.
The Earth's mantle is a layer of silicate rock between the crust and the outer core.

Seismic wave

seismic wavesseismic velocitybody wave
Seismic inversions of body waves and normal modes constrain the radius of the outer core to be 3483 km with an uncertainty of 5 km, while that of the inner core is 1220±10 km. Evidence for a fluid outer core includes from seismology which shows that seismic shear-waves are not transmitted through the outer core.
Velocity tends to increase with depth through Earth's crust and mantle, but drops sharply going from the mantle to the outer core.

S-wave

shear waveS-wavesshear
Evidence for a fluid outer core includes from seismology which shows that seismic shear-waves are not transmitted through the outer core.
Unlike the P-wave, the S-wave cannot travel through the molten outer core of the Earth, and this causes a shadow zone for S-waves opposite to where they originate.

Earth's magnetic field

geomagnetismgeomagneticgeomagnetic field
The Dynamo theory sees eddy currents in the nickel–iron fluid of the outer core as principal source of the Earth's magnetic field.
The magnetic field is generated by electric currents due to the motion of convection currents of molten iron in the Earth's outer core: these convection currents are caused by heat escaping from the core, a natural process called a geodynamo.

Seismology

seismicseismologistseismologists
Evidence for a fluid outer core includes from seismology which shows that seismic shear-waves are not transmitted through the outer core.
One of the earliest important discoveries (suggested by Richard Dixon Oldham in 1906 and definitively shown by Harold Jeffreys in 1926) was that the outer core of the earth is liquid.

Magnetic field

magnetic fieldsmagneticmagnetic flux density
The average magnetic field strength in the Earth's outer core was estimated to be 2.5 millitesla, 50 times stronger than the magnetic field at the surface.
The Earth's magnetic field is produced by convection of a liquid iron alloy in the outer core.

Liquid

liquidsliquid phaseliquid state
Unlike the inner (or solid ) core, the outer core is liquid.

Viscosity

viscouskinematic viscositydynamic viscosity
Because of its high temperature, modeling work has shown that the outer core is a low-viscosity fluid that convects turbulently.

Turbulence

turbulentturbulent flowatmospheric turbulence
Because of its high temperature, modeling work has shown that the outer core is a low-viscosity fluid that convects turbulently.

Dynamo theory

dynamogeodynamogeodynamo effect
The Dynamo theory sees eddy currents in the nickel–iron fluid of the outer core as principal source of the Earth's magnetic field.

Eddy current

eddy currentseddyeddy-current
The Dynamo theory sees eddy currents in the nickel–iron fluid of the outer core as principal source of the Earth's magnetic field.

Tesla (unit)

teslaTteslas
The average magnetic field strength in the Earth's outer core was estimated to be 2.5 millitesla, 50 times stronger than the magnetic field at the surface.

Sulfur

sulphurSbrimstone
Sulfur and oxygen could be present in the outer core.

Oxygen

OO 2 molecular oxygen
Sulfur and oxygen could be present in the outer core.

Earth's mantle

mantleEarth mantle
The Earth's mantle is a layer of silicate rock between the crust and the outer core.

Earth

Earth's surfaceterrestrialworld
Earth's interior remains active with a solid iron inner core, a liquid outer core that generates the Earth's magnetic field and a convecting mantle that drives plate tectonics.

Structure of the Earth

Earth's coreEarth's interiorcore
The internal structure of the Earth is layered in spherical shells: an outer silicate solid crust, a highly viscous asthenosphere and mantle, a liquid outer core that is much less viscous than the mantle, and a solid inner core.

Large low-shear-velocity provinces

superplumeLarge Low Shear-wave Velocity Provinceslarge low-shear-velocity province
Large low-shear-velocity provinces, LLSVPs, also called LLVPs or superplumes, are characteristic structures of parts of the lowermost mantle (the region surrounding the outer core) of the Earth.

Deep water cycle

whole-Earth water cycle
Some of the water makes it all the way to the lower mantle and may even reach the outer core.

North Magnetic Pole

magnetic northMagnetic North PoleNorth
The North Magnetic Pole moves over time due to magnetic changes in Earth's core.

Lower mantle (Earth)

lower mantlelower part
The lower mantle represents approximately 56% of the Earth's total volume, and is the region from 660 to 2900 km below the Earth's surface; between the transition zone and the outer core.