EQ 1

Question 1

What percentage of eq’s are found in the ring of Fire , Pacific Ocean?

Answer 1

70%

Question 2

Describe one area of active volcanoes that are associated with plumes from hotspots rather than inter-plate boundaries?

Answer 2

The Hawaiian islands are formed as a result of a tectonic plate moving over a stationary hotspot. the volcanoes are rafted away and new ones form in their place producing a chain of volcanoes

Question 3

what is a divergent plate boundary ?

Answer 3

also known as a constructive PB; two plates move away from each other , frequent in the ocean ‘spreading ridges’ and so it is seen as typically low risk
- creating rift volcanoes - less explosive and less effusive and under ocean

Question 4

what is a convergent plate boundary ?

Answer 4

also known as a destructive plate boundary where an oceanic and continental plate move towards each other, forming a subduction zone or continental collision depending on the type of plate . causing frequent earthquakes and volcanoes

Question 5

what is a conservative plate boundary?

Answer 5

where one plate slides against another, movement is either sinistral , dextral or horizontal
cons. plate boundaries do result in volcanic activity however they are the site of extensive shallow focus earthquakes - sometimes of considerable mag.

Question 6

How is a subduction zone formed?

Answer 6

A dense oceanic plate collides with a less dense continental plate and the ocean plate is typically thrust underneath because of greater buoyancy of the continental lithosphere, forming a subduction zone

Question 7

explain the process of a hotspot volcano formation

Answer 7

anomalous volcanism;
heat rises from the mantle as a hot thermal plume
high heat and low pressure at the base of the lithosphere enable the melting of the rock.
This molten magma material rises through cracks and erupts to from active volcanoes on the Earth’s surface

Question 8

Nepal earthquake 2015 how many killed via landslides ?

Answer 8

8000 out of 9000

Question 9

Nepal earthquake 2015;

magnitude of EQ?

Answer 9

7.8

Question 10

Nepal earthquake 2015;

GDP of nepal ?

Answer 10

$24.4 bln USD

Question 11

Nepal earthquake 2015;

How many houses collapsed?

Answer 11

1/2 mln , 92% owner built in rural areas , 82% in urban areas

Question 12

Nepal earthquake 2015;

effects of secondary effects ; liquefaction?

Answer 12

• mass burials of villages in the East of Nepal , mountainous regions with unconsolidated sediment = Landslides
• Especially villages in the langtang region , still under recovery

Question 13

Christchurch earthquake 2011;

Deaths?

Answer 13

185 , none directly via liquefaction

Question 14

Christchurch earthquake 2011;

Mag. ?

Answer 14

6.2

Question 15

Christchurch earthquake 2011;

GDP of New zealand and how much Christchurch makes up for it?

Answer 15

nearly $170 bln , Christchurch makes up for 10% of GDP

Question 16

Christchurch earthquake 2011;

primary effects of EQ?

Answer 16

• 185 deaths
• 100,000 houses damaged by ground shaking
• sewerage and water pipes also damaged , taking 5 months to be restored
• within those 5 months 1/5 of pop. migrated out of the city
• closure of businesses = negative effect on econ.

Question 17

conclusion for primary and secondary hazard effects?

Answer 17

Vary according to the countries GDP and governance, ultimately effects the mitigation , preparation and response process.

Question 18

define liquefaction

Answer 18

when a saturated/ partially saturated soil loses strength and stiffness in response to an applied stress such as shaking during an earthquake , material thats ordinarily like solid behaves like liquid.