earthquakes

What is the 2 plates New Zealand sits on?

Indo-Australian plate and the pacific plate.

What is an Epicenter?

An epicenter is the point on Earth's surface directly above where an earthquake begins.

What is a Hypocenter?

A hypocenter is the exact point underground where an earthquake begins.

What does propagate mean in geography terms?

How seismic energy travels through the layers of the Earth from the focus.

What are convection currents?

The driving force of plate movement caused by heat rising from the core.

What are Primary waves

Primary waves (or P-waves) are the fastest seismic waves produced by an earthquake, moving through the Earth by compressing and expanding the ground.

What are Secondary waves

Secondary waves (or S-waves) are the second type of seismic wave to arrive during an earthquake, moving the ground side-to-side (transverse waves)

What is the lithosphere?

the rigid outer part of the earth, consisting of the crust and upper mantle.

What is subduction?

Subduction is the process where one tectonic plate sinks beneath another into the mantle.

What happens when continental plates collide?

When continental plates collide they form fold mountains (eg. the Himalayas).

What happens when an oceanic plate and a continental plate collide?

Subduction. The oceanic plate is heavier so it sinks beneath the continental plate into the mantle.

What happens when two oceanic plates collide?

the older plate (more dense) sinks beneath the younger plate (less dense).

What is a transform boundary?

When to plates meet and one moves one direction and the other plate moves the opposite direction. This builds up pressure and then releases powerful earthquakes.

What is a convergent boundary?

the place where two plates come together, or converge, the result of a collision

What is a divergent boundary?

the place where two plates move apart, or diverge.

What is the order of waves that occur during an earthquake? (S waves, P wave, Surface waves)

(P) waves, (S) waves, Surface waves.

What are surface waves?

Earthquake waves that travel along the surface of the earth not through the Earth (rolling type wave). These are the last waves to arrive.

What is a person called that studies earthquakes?

Seismologist

What is used to measure the magnitude of an earthquake?

Seismograph or a Moment Magnitude Scale

What scale is used to measure the intensity of an earthquake?

The Mercalli scale

What are the two different types of plates?

continental and oceanic

What can P waves travel through?

solids and liquids

What can S waves travel through?

only solids

What can surface waves travel through?

only the surface

what do P waves do as they travel through earth

They compress and stretch the earth like a slinky.

What do S waves do as they travel through the earth

Secondary (S) waves shake the ground side-to-side or up-and-down

What do surface waves do as they travel through the earth?

Surface waves are earthquake vibrations that roll across the surface.

What does SPENT stand for?

S - Social factors

P - Political factors

E - Economic factors

N - Natural events

T - Technological factors

Date and time it happened?

Tuesday 22nd February 2011 at 12:51pm

Location?

Christchurch and Lyttelton.

magnitude?

6.3

Depth?

5km below the surface

Two immediate impacts?

Loss of lives (185) and Structural failure (CTV building, Pyne Gould Corporation building, Christchurch cathedral)

cause?

The earthquake was caused by the sudden rupture of a hidden fault line and was a delayed aftershock of the Darfield earthquake.

Proper name of the earthquake?

February 2011 Christchurch earthquake

Two longer term impacts?

Suburban Red Zoning (because of liquefaction) and Building & Insurance Reforms

two social impacts?

psychological distress and grief from the loss of lives.

two economic impacts?

$40 billion rebuilding cost and lack of tourists bringing money in after the earthquake.

Two environmental impacts?

Widespread land damage from liquefaction, which permanently altered Christchurch's geography, waterways, and soil structure.

immediate responses?

The immediate response to the earthquake was rescue, restoring critical infrastructure under a national state of emergency.

long term responses/ recovery?

The long-term response to the earthquake was a multi-decade focus on rebuilding infrastructure and trying to relieve the multi-decade mental health trauma in the community.

Tectonic setting?

The earthquake occurred 100km away from the boundary of the Pacific and Indo-Australian plates.