GEOGRAPHICAL PHENOMENA

PLATE TECTONICS

BRIEF INSIGHT

• MODULE:1• Section-5• Objectives • (a)- What is plate tectonics?• (b)- Location and movement of the Caribbean plate and it’s interaction

with other plates• (c)- Earthquakes and volcanoes: threat of tsunami, social development

EXTERNAL VIDEO

https://m.youtube.com/?#/watch?v=JGXi_9A__Vc

WHAT IS PLATE TECTONICS?

• Basic definition of plate tectonics;

Plate tectonics is an explanation of how plates move in relation to each other, thereby, creating certain tectonic activities at their margin.

• Geographical definition of plate tectonics;

Plate tectonics refers to the theory that the Earth’s surface(lithosphere), which holds landmass especially and oceans, is moving relatively over a dense semi-liquid area below the surface (asthenosphere). Motion is influenced by friction between the asthenosphere and lithosphere, causing the rigid surface to fracture and move as individual plates.

PLATE MOVEMENT Transform (conservative) plate margins

These are plates that slide past each other. They generate earthquakes.

e.g:

• Trinidad

• Jamaica

• Haiti

• Puerto rico

Divergent(constructive) plate margins;

It is a linear feauture which moves away from each other. These movements usually generate volcanoes.

e.g;

• Grenada- Kick ‘em Jenny

• Martinique- Mt. Pele

• Monsterrat- Soufriére

• St. Lucia – Pitons

PLATE MOVEMENT

Picture showing the various volcanoes in the caribbean

Mt soufrieire in Monsterrat before eruption The Soufrière Hills volcano is an active, complex stratovolcano with many lava domes forming its summit, on the Caribbean island of Montserrat. After a long period of dormancy, the Soufrière Hills volcano became active in 1995, and has continued to erupt ever since. Its eruptions have rendered more than half of Montserrat uninhabitable, destroying the capital city, Plymouth, and causing widespread evacuations: about two thirds of the population have left the island.

After eruption in 2012

PLATE MOVEMENT

Convergent(destructive) plate margin;

This is occurs when plates collides and one is forced downwards, hence pushing upward the other plate.as a result there are volcanoes, earthquakes and mountains being formed in these areas.

e.g; volcanoes (repeated)

• Grenada- Kick ‘em Jenny

• Martinique- Mt. Pele

• Monsterrat- Soufriére.

e.g: mountains

• Trinidad- northern range

• Jamaica- Blue Mountains

• Grenada- Saint Catherine

CARIBBEAN PLATE The Caribbean Plate is centered amidst the Cocos, Panama, North Andes, South American, and North American Plates.

The Caribbean Plate lies in a complex area with two major plates and two minor plates bordering it. The plate includes oceanic and continental crust. The Caribbean Sea covers most of the plate with Central America and volcanic islands covering the rest. The edges of the plate have intense seismic activity, frequent earthquakes and volcanic eruptions.

DISASTERS CAUSED BY PLATE TECTONICS

• Earthquakes are sudden tremors in the earth cause by plate movements, hey are sudden, striking and comes with little movements.

The violent seismic waves destroy buildings an kill and injure people buried under the rubble. They may trigger landslides and damage dams. However, they are most common along the northern and western fringes of the caribbean society.

e.G

Jamaica (1907)

The capital city, Kingston was flatten secondary impact of fires caused further damage.

Haiti (2010)

The impact of the massive earthquake has been one of the most devastating. It occurred on the 12th of January with a magnitude of 7.0. Today, Haiti still has not recovered leaving hundreds in abject poverty, others homeless and much more facing economical problems.

RELATIVE TERMS

firstly, the term natural hazards can be defined as events that occur on the earth’s surface and cause a threat to human lives and property.

Natural disaster- events that occur on the earth’s crust and affects human lives and property causing a detrimental effect.

EXTERNAL VIDEO

DISASTERS CAUSED BY PLATE TECTONICS

• A tsunami is a large sea wave, travelling at great speed, triggered by oceanic earthquakes and volcanoes.

Tsunamis are not familiar to the caribbean, however there have been minor impacts on recent history. These includes;

• Jamaica (1907)

• Puerto Rico (1918)

• Mosterrat (1997)

• Dominican Republic (1946)

DISASTERS CAUSED BY PLATE TECTONICS

• Volcanoes are perhaps the most dramatic extreme natural event. Hot lava spewing out of the vent, Ash and gases exploding into the air.the impact can be devastating, obliterating large areas, with people and buildings buried.

There are two types of volcano: composite, cinder and shield.

EXTERNAL VIDEO

ADDITIONAL READYING INFORMATION IS PLACED ON THE HANDOUT

• These include the impact of earthquakes and volcanoes

• Also more detailed information on plate tectonics.

THE END PRESENTATION BY:

GABRIELLE RAMROD

SUDESH BE HARRYLAL

KEVIN RAMRATTAN