Paper 1- Tectonic hazards

Question 1

where are volcanos found?

Answer 1

Wherever magma rises to the surface: conservative margins, subduction zones and hot spots

Question 2

What three substances do volcanos emit

Answer 2

Lava, pyroclastic material, Gases

Question 3

While magma is molten rock beneath the surface, lava is…

Answer 3

magma running over the surfcae

Question 4

Acid lava characteristics

Answer 4

High silica content

temp around 700 degrees

very viscous, sticky

forms rhyolite or andesite rock

associated with destructive plate margins

Question 5

Basic lava characteristics

Answer 5

Low silica content

Temp around 1200 degrees

non-viscous, runny

forms basalt rock

associated with tensional margins and hot spots

Question 6

why are acid eruptions more dangerous?

Answer 6

Pockets of gas - when exploding its sticky

Question 7

Example of a shield volcano

Answer 7

Mauna Hoa in Hawaii

Question 8

Example of a composite cone (strato volcano

Answer 8

Mt Fuji

Mt Rainier

Question 9

Lava flow primary impact

Answer 9

Eruption of Eldfell, at Haimaey, Iceland 1973

lava destroyed over 300 buildings.

But town and fishing port were saved by spraying water

Question 10

Pyroclastic flow primary impact

Answer 10

E.g. Eruptionn of mt. Pelée, Martinique in 1902

A hot ash cloud wiped out St Pierre, over 25,000 deaths

Question 11

Ash and ash fal primary impact

Answer 11

E.g. Eyjafallajokull, Iceland 2010

Glacier ice on top of the erupting volcano cause a huge ash cloud that caused over 100,000 flight cancelations and around 1bn dollars

Question 12

Volcanic gases primary impact

Answer 12

E.g. Lake Nyos volcano, Cameroon in 1986

A large cloud of CO2 was released from the lake within the crater, this travelled downhill 15 miles, killing 1700 people

Question 13

Volcanic mudflows (lahars) secondary impact

Answer 13

Eruption of Nevado del Ruiz, Colombia in 19985

Volcanic ash and rocks mixed with snow and ice on mountaintop to produce lahar

Swept across the town of Armero killing 23,000 people

Question 14

Tsunamis secondary impact

Answer 14

E.g. Eruption of Krakatau, Indonesia in 1883

caused the collapse of the island producing large tsunamis that killed 36,000 people

Question 15

VEI - Volcanic Explosive index

Answer 15

from 0 to 8

Each step up from 2 is a 10x increase in the volume of solid material produced by the eruption

E.g. 1km^3 Mt St Helens

Super volcano 10,000km^3

Question 16

Earthquake definition

Answer 16

Sudden ground movements/ Earth tremors

Occurs, when crystal rock accumulates strain the suddenly moves or breaks along a fault

Energy is released in the form of Seismic waves

Question 17

“focus” of an earthquake

Answer 17

The point within the crust where the earthquake rupture starts

Question 18

Epicentre

Answer 18

The point on the ground directly above the focus

Question 19

The Richter scale

Answer 19

Measures magnitude of earthquake

Determined using seismographs

Scale is logarithmic

Tectonic forces capable of generating earthquakes no stronger than al little over nine on the richter scale

Earthquakes low on R scale are more frequent

Question 20

What is the Mercalli scale

Answer 20

Measures the devastation of an earthquake on a 12 point scale

A subjective assesment of damage done

Question 21

Primary impacts of a strong earthquake

Answer 21

Fault scarps/ surface ruptures

collapsed buildings

damaged infrastructure

Question 22

secondary impacts of an earthquake

Answer 22

fire

landslides

tsunamis

Liquefaction - makes water more liquid than solid

Disease and famine

Question 23

What is meant by primary and secondary effects of tectonic events?

Answer 23

Primary refers to direct effects on people + infrastructure

e.g. casualties and building damage

Secondary effects are triggered by the initial event

e.g lanslides due to slopes made unstable

+ Economic factors

Question 24

Immediate and long term responses to tectonic events meaning

Answer 24

Immediate refers to rapid emergency response

Long term = delayed and long duration responses

e.g. Government stratergies to rebuild

Question 25

Why do HICs fare better than LICs countries in disasters

Answer 25

HICs have more awareness HICs have better methods of mapping and monitoring the hazards Often corruption in LICS HICs have more money to spend on emergency services E.g. Mount St. Helens USA 1998 careful monitoring and evacuation resulted in less causualties (57 deaths) E.g Nevado del Ruiz, Colombia (1985) lack of careful monitoring lead to 23,00 casualties

Question 26

Haiti background information earhtquake

Answer 26

Took place on 13th Jan 2010 Struck a local time of 16:50 Magnitude was 7.0 on richter scale Haiti lies between Caribbean + North American plate Arose at a fault which runs through Haiti

Question 27

Christchurch NZ background information earthquake

Answer 27

Suffered from its previous earthquake that year Situated in South Island Home to around 400,000 people Hit on 22nd Feb 2011 6.3 on the Richter scale Epicentre was around 6km from Christchurch

Question 28

Primary Haiti impacts

Answer 28

Primary: 230,000 people died, 300,000 injured, 1 million left homeless, 250,000 residential buildings + 30,000 commercial buildings were destroyed, their buildings were made cheaply, could be due to corruption

Question 29

Secondary Hait impacts

Answer 29

Secondary: impact on industry, main production was clothing. 17th largest supplier of clothing products sold to USA in 2008, left economy poorer and prices raised due to demand, tourism effected e.g Cruise ships, airlines and hotels were in demand - quake destroyed this Farming 5 - 6 million lived in rural areas 85% of those people framed accounts for 26% of Haiti's economic output ruined crops, cattle + roads - slowed operation down before the earthquake priorities were focused on feeding pop.

Question 30

Christchurch primary impacts

Answer 30

loss of buildings old city centre was destroyed this cost round 10$ billion to redevelop the city the other $10 billion was for other areas 185 people killed 6000 injured

Question 31

Christchurch secondary impacts

Answer 31

Landslides glacial falling into the seas Rugby world cup had to be moved- effecting the local economy

Question 32

Haiti responses

Answer 32

Rescue those trapped in rubble Main hospital was destroyed Health needs were addressed by 6 international + 8 haitian medical teams People desperately needed basics UK disaster comittee donated £23 million US sent aid by sending planes full of rescue workers and ships with thousands of soldiers Long term respones = charities--> infrastructure + medical resources

Question 33

Christchurch response

Answer 33

needs of the local people Plans to demolish the old city centre core Long term responses came two years late: Job creation, innovation, well being for the locals other support was fundraised (8.8 billion dollars) Provided sewage, road and transport needs Some say good came from it = oppertunity to redevelop Planned stratergies fro Christchurch 1 = government to redevelop the town (20 billion $) e.g. economic growth, leadership, awareness 2="Christchurch central development plan" Aim was for a new central core, significant points to show strength of city, local people got involved, brought community closer