UNIT 2. RELIEF

VEO, PIENSO, ME PREGUNTO 

SEE, THINK, WONDER

 

1. LOOKING INSIDE THE EARTH



First, let’s clarify what we’re studying here: the geosphere. To sum up, the geosphere is the solid part of the Earth where living things live.

What’s the point in knowing the inner structure of the Earth?
Well, only by knowing it, we can understand how the relief is created. So, take a look at this video








This animations with will make it clearer for you.





A BRIEF HISTORY OF GEOLOGIC TIME
 
 

 


2. THE SURFACE OF THE EARTH IS MOVING! HOW THE RELIEF IS FORMED

TECTONIC PLATES AND CONTINENTAL DRIFT


Yes, that’s right. The lithosphere (crust and upper mantle) is cracked.
There are several pieces called plates which slowly move due to inner forces of the Earth. The plates collide or separate creating new relief forms and other phenomena. We call this plate tectonics.

Here's how it works

























LA DERIVA CONTINENTAL Y LAS CÉLULAS DE CONVECCIÓN DEL MANTO





Want more visual help?
 
This animation shows the different plates in the world. You can set the options and watch the movements.  
        





THE THREE BASIC MOVEMENTS OF THE PLATES. PLATES BOUNDARIES

 

 

 

 


You can learn the basics by watching this animation:

 

 

 
 

 
 

 
 
 
 
 


 


Let’s explain everything a bit more

a.  COLLISION (convergent boundaries)


The first thing we need to have into account is that some plates are thinner and some are thicker. Ocean plates are thinner than continental plates. Knowing this, the collision can occur in different ways:


-     Collision between an oceanic and a continental plate


  


The ocean plate, thinner, slides under the continental Pate. This process in called subduction. There are lots of earthquakes and volcanic eruptions. 
The oceanic plate melts as it re-enters the mantle. The magma rises and erupts. This creates a volcanic mountain range near the coast of the continent. This range is called a continental or volcanic arc.

 


Did you know that The Andes Mountains are a volcanic arc created by the collision of the Nazca plate and the South American Plate?







-     Collision between an oceanic and another oceanic plate




 
When two oceanic plates collide, one usually slides under the other, and in the process a trench is formed. Also, a lot of volcanoes are erupt.


Over millions of years, the erupted lava and volcanic debris pile up on the ocean floor until a submarine volcano rises above sea level to form an island volcano or even a volcanic arc.



As an example, the Marianas islands and Marianas Trench

 



Japan


 FIND OUT!

Another wonderful example are the Aleutian Islands next to Alaska. Can you find them using Google Earth?  Explore the area and locate the trench.


- Collision between a continental and another continental plate.







When two continental plates collide, neither is subducted. Instead, the crust usually folds upwards creating mountain ranges.



The Himalayas is a good example of this case.




 





  b.  Separation (divergent boundaries)

We find divergent boundaries where plates are moving apart and new crust is created by magma pushing up from the mantle.

Perhaps the best known of the divergent boundaries is the Mid-Atlantic Ridge. Seafloor spreading over the past 100 to 200 million years has caused the Atlantic Ocean to grow from a tiny inlet of water between the continents of Europe, Africa, and the Americas into the vast ocean that exists today. 

Iceland is in its way and it’s cracking in two.



 



FIND OUT!

Can you find the Md-Atlantic Ridge using Google Earth? 


c.  Transform boundaries


When two plates slide horizontally. Also called transform faultS.
 

  
Most transform faults are on the ocean floor. They move in a zig zag way and produce earthquakes.

There are a few on land. For example, the San Andreas Fault zone in California.






 

HOT SPOTS 

What are hot spots?

In geology, hot spots are volcanic regions where the mantle is particularly hot compared with the surrounding mantle.



 
Plates on the move game
  



FOLDS AND FAULTS

 


Deformaciones de la Corteza: Fallas Geológicas


FOLDS

 cytisan [licensed for non-commercial use only] / Pliegues y fallas

 

Archivo:Agiospavlos DM 2004 IMG002 Felsenformation.JPG - Wikipedia, la  enciclopedia libre



FAULTS

Faults and Folds Flashcards | Quizlet
GeoPicture of the Week: Geologic Faults


78 ideas de _GEO / EARTH TECTÓNICA | geología, tectonica de placas,  ciencias de la tierra




THE SHAPING OF RELIEF

Wall picture discussion:

¿how was it shaped?

Turismo de naturaleza en Navarra | Visit Navarra - Web Oficial de Turismo  de Navarra

AGENTES PROTAGONISTAS DEL MODELADO DEL RELIEVE


 

 

¿CÓMO SE PRODUCEN ESTOS CAMBIOS?

 

 


MAIN LANDSCAPE FORMS

 


COASTAL RELIEF


 

 

OCEAN FLOOR RELIEF

 

 


RELIEVE CONTINENTAL, COSTERO Y SUBMARINO


https://geografiaehistoriapabloserranozaragoza.files.wordpress.com/2012/10/relieve1.jpg 

1. Ría     2. Cabo   3. Península   4. Isla   5. Golfo   6. Dorsal Oceánica    7. Fosa marina    
8. Llanura abisal    9. Plataforma continental   10. Talud continental   11. Montaña
12. Depresión o cuenca   13. Valle   14. Meseta    15. Llanura



GEOLOGICAL HAZARDS


VOLCANOES

 

 

Pincha en la siguiente imagen  para interactuar con las partes de un volcán


 

 

 volcan al completo

  Evolución del volcán de la Palma: vídeo

  Explicación del volcán de la Palma: vídeo

 

EARTHQUAKES


 
 

Types Of Seismic Activity

 

 What Causes an Earthquake, and What Happens During a Quake? | Caltech  Science Exchange

 

Earthquake-prone Regions Of The World

The Pacific Ring of Fire



Measurement Of Earthquakes




Asismet on Twitter: "La profundidad se refiere a la distancia entre el  epicentro y el lugar donde se origina el sismo (foco sísmico o hipocentro).  Tenga en cuenta que el epicentro no

 

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