Cavs geography blog 2.2

What is a landslide? Describe the main causes of landslides. In what way can human actions contribute to landslides?

A landslide is movement in the earth's crust that triggers large amounts of earth to suddenly shift destroying everything in its path. Human cause landslides when they build upon weak founadtion and put severe pressure upon the earth until eventually it gives way.

Corrosion, terrential rain, human action, earthquakes, volcanic action are all causes of landslides.

Building of roads and railways as well as devegetation can all cause landslides.

What are earthquakes and how are they measured?

Earth quakes are the movement of tech-tonics plates and are measued on the ricta scale

What is the main cause of earthquakes in Australia?

Tech tonic movement.

How frequently does Australia experience earthquakes of 5.5 on the Richter scale and why do they usually have minimal impacts on communities?

Every 15 months one hits Australia but they cause miniaml damage due to communities having lower population ratios to higher land occupation. 

List the impacts of the 1989 earthquake on the Newcastle community.

It killed 13 people and injured 113 as well as destroyed thousands of homes

Describe the difference between a landslide and an earthquake.

Lanslides are caused by weather most often and are not as large as earthquakes. Earthquakes are caused by tech-tonic movement and can effect far larger communities of people.

What is a tsunami?

A tsunami is a wave caused by movement of the earth's crust.

Name three events that will cause a tsunami.

Earthqaukes, landslides and volcanic eruptions all cause tsunamis

With the aid of a diagram, explain how a tsunami is formed.

When an earthquake hits it creates the crust to suddenly uplift causing millions of tonnes of water to suddenly rise above the ocean surface and travel out form epicentre 

Describe three tsunami warning signs.

Waves suddenly grow, suddenly retreat of water, sea life is revealed, wave resembles violent flood of water.  

What caused the Indian Ocean tsunami of 2004?

The tsunami was caused by an earthquake suddenlly displacing millions of tonnes of water that raced out from the epicentre at unimaginable speeds caused incredible damage to the beach communities throughout the Indian Ocean.
There are 23 Erathquake moniter stations in Australia and only took one of these stations 20 minutes to pick up the 2004 Indian Ocean earthqauke.

Describe how a tsunami changes as it enters shallow water.

As it enters the shallow water it compresses rising far above the ocean surface and resembles a huge wall of water racing towards you.  

What steps has the United Nations taken to safeguard Indian cean communities from the tsunami hazard?
They have taken extra precautions in placing numerous moniters in the Indain Ocean so in the event of a tsunami they can be notified immediatley of the incoming wave and evacuate the sea side communities.  
Who is Ted Bryant? What warning does he issue in regard to tsunamis for Australia?

He is a geoscience professor and warned that qaukes on New Zealends Alpine fault line could hit Australia once every 500 years.