LITHOSPHERE

Patterns & Processes

PATTERNSEarthquakes, Volcanoes and Tectonic Plates

Distribution of EarthquakesDistribution of EarthquakesDistribution of Volcanoes

So, what is going on?So, what is going on?

Can you mark out a distinct Can you mark out a distinct pattern from the distribution pattern from the distribution

of earthquakes and of earthquakes and volcanoes?volcanoes?

Distribution of Tectonic PlatesDistribution of Tectonic Plates

So what if we have the plates So what if we have the plates in place?in place?

What must happen to the What must happen to the plates?plates?

What can cause this to What can cause this to happen to the plates?happen to the plates?

Where would it come from?Where would it come from?

Tada! You have just guessed Tada! You have just guessed the structure of the Earth!the structure of the Earth!

STRUCTURE OF THE EARTH

Ferrero Rocher Earth

Structure of the EarthStructure of the Earth

CoreCoreLayer rich in iron and nickelLayer rich in iron and nickelSize of Mars!Size of Mars!Inner and outerInner and outer– Inner: Solid, density of 13g/cm3, radius of Inner: Solid, density of 13g/cm3, radius of

1220km1220km– Outer core: Liquid, density of 11g/cm3, Outer core: Liquid, density of 11g/cm3,

average thickness of 2250kmaverage thickness of 2250km

Temperature is about 6200 degrees Temperature is about 6200 degrees Celsius, hotter than the surface of the Celsius, hotter than the surface of the Sun!!!Sun!!!

MantleMantleAlmost 2900 km thick, comprises about Almost 2900 km thick, comprises about 83% Earth’s volume83% Earth’s volumeUpper mantle: Upper mantle: – From crust downward to a depth of about 670 km From crust downward to a depth of about 670 km – Asthenosphere: top layer of the upper mantle, 100 to Asthenosphere: top layer of the upper mantle, 100 to

200 km200 kmMore rigid and brittle because of cooler More rigid and brittle because of cooler temperatures and lower pressurestemperatures and lower pressures

Lower mantle:Lower mantle:– From 670 to 2900 km below the Earth's surface. From 670 to 2900 km below the Earth's surface. – Hot and plasticHot and plastic– Higher pressure causes the formation of minerals Higher pressure causes the formation of minerals

different from those of the upper mantledifferent from those of the upper mantle

CrustCrustAs thin as a sheet of paper if earth As thin as a sheet of paper if earth were a basketball were a basketball Cool, rigid, and brittleCool, rigid, and brittleTwo types of crust can be Two types of crust can be identified: oceanic and continentalidentified: oceanic and continental– Oceanic (sima)Oceanic (sima)

Mainly basalt, averaging 6 to 10 kmMainly basalt, averaging 6 to 10 kmAt its deepest has a temperature of At its deepest has a temperature of 1200 degrees Celsius1200 degrees Celsius

– Continental (sial)Continental (sial)GraniticGraniticCan be up to 70 km thickCan be up to 70 km thick

LithosphereLithosphereIncludes the crust and the upper most portion of the Includes the crust and the upper most portion of the asthenosphere asthenosphere About 100 km thick About 100 km thick Has the ability to glide over the rest of the upper mantleHas the ability to glide over the rest of the upper mantleZone of earthquakes, mountain building, volcanoes and Zone of earthquakes, mountain building, volcanoes and continental driftcontinental drift

But how did we find out what But how did we find out what the structure of the Earth is like?the structure of the Earth is like?