Structure of the Earth The Earth is made up of 3 main layers: ______________

The Crust This is where we live! The Earth’s crust is made of: _________________ - thick (10-70km) - buoyant (_____ _______ than oceanic crust) - mostly old __________________ - thin (~7 km) - dense (_______ under continental crust) - young

What is Plate Tectonics?

If you look at a map of the world, you may notice that some of the continents could fit together like pieces of a puzzle.

Plate Tectonics The Earth’s crust is divided into ___ major plates which are moved in various directions. This plate motion causes them to __________, ______ _______, or __________ against each other. Each type of interaction causes a characteristic set of Earth structures or “tectonic” features. The word, tectonic, refers to the ___________ of the crust as a consequence of plate interaction.

World Plates

What are tectonic plates made of? Plates are made of rigid ____________. The lithosphere is made up of the _________and the upper part of the __________.

What lies beneath the tectonic plates? Below the lithosphere (which makes up the tectonic plates) is the ____________.

Plate Movement “Plates” of lithosphere are moved around by the underlying hot mantle ___________ cells. Source: Your Planet Earth

The Action Is At The Plate Boundaries!

____________ Three types of plate boundaries Source: Your Planet Earth

Spreading ridges  _______________________________________ _______________________________________ Divergent Boundaries Source: Your Planet Earth

Age of Oceanic Crust Courtesy of

Iceland has a ___________ plate boundary running through its middle Iceland: An example of _______________ __________ Source: Your Planet Earth

There are three styles of convergent plate boundaries  __________________________________ Convergent Boundaries

Forms mountains, e.g. ________________ and _____________________ Continent-Continent Collision

Himalayas

Called __________________ Continent-Oceanic Crust Collision Source: Your Planet Earth

_________ ___________ subducts underneath the continental lithosphere Oceanic lithosphere heats and dehydrates as it subsides The melt rises forming ___________ E.g. _____ _________ Subduction Source: Your Planet Earth

When two oceanic plates collide, one runs over the other which causes it to _________ into the mantle forming a _____________ _________. The subducting plate is bent downward to form a _____ ________ depression in the ocean floor called a __________. The worlds deepest parts of the ocean are found along trenches.  E.g. The Mariana Trench is _____ ________! Ocean-Ocean Plate Collision

Where plates _______ ______ each other Transform Boundaries Above: View of the San Andreas transform fault Source: Your Planet Earth