THE CORE Flashcards
very hot, very dense center of our planet
ball-shaped core lies beneath the cool, brittle crust and the mostly solid mantle
THE CORE
is the furnace of the geothermal gradient.
geothermal gradient measures the increase of heat and pressure in Earth’s interior
THE CORE
primary contributors to heat in the core are the decay of radioactive elements, leftover heat from planetary
formation, and heat released as the liquid outer core solidifies near its boundary with the inner core
THE CORE
LAYERS OF THE CORE
OUTER CORE
INNER CORE
mostly composed of liquid iron and nickel
THE OUTER CORE
NiFe alloy of the outer core is very hot, between
4,500° and 5,500° Celsius (8,132° and 9,932° Fahrenheit)
liquid metal of the outer core has very low viscosity, meaning it is easily deformed and malleable
site of violent convection
churning metal of the outer core creates and sustains Earth’s magnetic field
THE OUTER CORE
The hottest part of the core is actually the
Bullen discontinuity,
Bullen discontinuity,
where temperatures reach
6,000° Celsius (10,800°
Fahrenheit)—
its as hot as the surface of the sun.
Bullen discontinuity
is a hot, dense ball of (mostly) iron
THE INNER CORE
THE INNER CORE temperature
about 5,200° Celsius (9,392° Fahrenheit)
The pressure is nearly 3.6 million atmosphere (atm).
the inner core is not liquid or even molten
inner core’s intense pressure prevents the iron from melting
THE INNER CORE
THE INNER CORE pressure
3.6 million atmosphere (atm).
pressure and density are simply too great for the iron atoms to move into a liquid state
some geophysicists prefer to interpret the inner core not as a solid, but as a plasma behaving as a solid
THE INNER CORE
