Processes of Lithosphere

Lithosphere Rigid outermost shell of a rocky planet – On earth, comprises the crust and the upper mantle

The Rock Cycle Thinking about relationships among the major rock groups

5 Major Rock Groups Igneous – Formed from a melt (molten rock) – Plutonic (intrusive):slow cooling and crystallization – Volcanic (extrusion): quick cooling at the surface Sedimentary – Formed at the Earth ’ s surface Metamorphic – Changed by pressure, temperature and fluids.

Fig. 2.9 MAGMA

7 Crystallization IGNEOUS

8 MAGMA IGNEOUS Plutonic Crystallization

9 MAGMA Volcanic IGNEOUS Plutonic Crystallization

10 MAGMA Volcanic IGNEOUS Plutonic Uplift Crystallization Weathering

Chemical – changing composition (acid rain) Physical – Breaking apart rocks, moving soils, etc Soil is result of weathering of rocks and includes weathered particles

12 MAGMA Volcanic IGNEOUS Plutonic SEDIMENT Uplift Crystallization Weathering SEDIMENT

13 MAGMA Volcanic IGNEOUS Plutonic SEDIMENT SEDIMENTARY Uplift Crystallization Weathering Erosion Transport Deposition

14 MAGMA Volcanic IGNEOUS Plutonic SEDIMENT SEDIMENTARY Uplift Crystallization Weathering Erosion Transport Deposition

15 MAGMA Volcanic IGNEOUS Plutonic SEDIMENT SEDIMENTARY METAMORPHIC Uplift Burial Increased P&T Crystallization Weathering Erosion Transport Deposition

16 MAGMA Volcanic IGNEOUS Plutonic SEDIMENT SEDIMENTARY METAMORPHIC Uplift Burial Increased P&T Melting Crystallization Weathering Erosion Transport Deposition Can you see any shortcuts?

17 MAGMA Volcanic IGNEOUS Plutonic SEDIMENT SEDIMENTARY METAMORPHIC Uplift Burial Increased P&T Melting Crystallization Weathering Erosion Transport Deposition

The rock cycle demonstrates the relationships among the three major rock groups It is powered by the interior heat of the Earth The energy from the sun It involves processes on the Earth ’ s surface as well as the Earth ’ s interior. In Conclusion…

The Structure of the Earth and Plate Tectonics

Structure of the Earth The Earth is made up of 3 main layers: – Core – Mantle – Crust Inner core Outer core Mantle Crust

The Crust This is where we live! The Earth’s crust is made of: Continental Crust - buoyant (less dense than oceanic crust) Oceanic Crust - dense (sinks under continental crust)

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 12 major plates which are moved in various directions. This plate motion causes them to collide, pull apart, or scrape against each other. Each type of interaction causes a characteristic set of Earth structures or “tectonic” features. The word, tectonic, refers to the deformation of the crust as a consequence of plate interaction.

World Plates

What are tectonic plates made of? Plates are made of rigid lithosphere. The lithosphere is made up of the crust and the upper part of the mantle.

Plate Movement “Plates” of lithosphere are moved around by the underlying hot mantle convection cells

Divergent Convergent Transform Three types of plate boundary

Spreading ridges – As plates move apart new material is erupted to fill the gap Divergent Boundaries

Iceland has a divergent plate boundary running through its middle Iceland: An example of continental rifting

There are three styles of convergent plate boundaries – Continent-continent collision – Continent-oceanic crust collision – Ocean-ocean collision Convergent Boundaries

Forms mountains, e.g. European Alps, Himalayas Continent-Continent Collision

Himalayas

Called SUBDUCTION Area is called the subduction zone Continent-Oceanic Crust Collision

Where plates slide past each other Transform Boundaries Above: View of the San Andreas transform fault

…what’s the connection? Volcanoes and Plate Tectonics…

Volcanism is mostly focused at plate margins Pacific Ring of Fire

- Subduction - Rifting - Hotspots Volcanoes are formed by:

Subduction Form new melt that will rise through the crust to be erupted at the surface

Rifting Form new melt that will rise through the crust to be erupted at the surface

Hot Spots Does not occur along a plate boundary. Form in the middle of tectonic plates

Volcanic Eruptions Pyroclastic Flow – cloud of ash and debris – Travel at hundreds of mph – Hundreds of degrees

Volcanic Eruptions Lahar – mud flows which are very destructive to landscape

Volcanic Eruptions “Ash” emitted includes small stones Very dense Chokes life Blots out sunlight Causes wide range temperature drops om/watch?v=UK-- hvgP2uY

…what’s the connection? Earthquakes and Plate Tectonics…

As with volcanoes, earthquakes are not randomly distributed over the globe At the boundaries between plates, friction causes them to stick together. When built up energy causes them to break, earthquakes occur. Figure showing the distribution of earthquakes around the globe

Where do earthquakes form? Figure showing the tectonic setting of earthquakes

Fault Lines Strike – slip Reverse Normal

Earthquake Anatomy Focal point – where the actual earth quake originated underground Epicenter – location of earth quake on earth’s surface – Above the focal point

Earthquake Anatomy P Waves (primary) – waves which travel fastest, first, and moves through any material – Reach seismographs – Moves land back and forth S Waves (secondary) – actual surface waves which travel slower and only moves through solids – Moves land up and down /primary-and-secondary-waves

Results.. Land destruction/alteration Fire (breaking of gas and power lines) Buildings destroyed Tsunami’s

Tsunami “Harbor Wave”