Tectonic Plates

Question 1

When two tectonic plates are moving away from eachpther what plate boundry is that? e.g <———->

Answer 1

Divergent plate boundry

Question 2

What is the crust?

Answer 2

Thinnest layer, 5-70Km, thinner under ocean than land, coldest layer, solid rock brockwn up into peices called tectonic plates

Question 3

What is the mantle?

Answer 3

Thickest layer, moves in slow big circles caused by convectional currents, aprrox 1000°C near crust and 3700°C near core, semi molten

Question 4

What is the outer core?

Answer 4

Semi liquid iron, temp between 3700° and 5000°C

Question 5

What is inner core?

Answer 5

Most inner part of earth, aprrox 1250km, hottest part of earth- temp over 5000°C, material very dense, rock solid

Question 6

What is Wegners theory?

Answer 6

Continents fit togther like a puzzle, believed continents used to be connected and called PANGAE, 200million years ago. Shifted away because of continental drfit

Question 7

What is the plate tectonic theory about convection currents?

Answer 7

Movements of volcanic rock in mantle rises to crust and sinks. As repeats scientists believe powerful enough to move earths plates

Question 8

When one tectonic plate slips under another one what is this called and what type of plate boundry is it?

Answer 8

This is called convergent plate boundry. The less dense continental plate moves towards denser oceanic plate and forced below this is called subduction. Subduction zone where earthquakes occur

Question 9

What is a conservative plate boundry?

Answer 9

Plates slide past eachother. Plates rub rock breakes causing earthquakes

Question 10

What is epicentre?

Answer 10

Point on ground above where an earthquake happens

Question 11

What is the fault line?

Answer 11

Line on earths surface that traces a geological fault

Question 12

What is stress and release?

Answer 12

Pressure builds up between two plateson fault line. Too much pressure is released

Question 13

What is primary shockwave?

Answer 13

Travel fowards, backwards and move quickly

Question 14

What are secondary shockwaves?

Answer 14

Slower and move sideways and up and down

Question 15

What is the richter scale?

Answer 15

Measures magnitude

Question 16

What is the mercalli scale?

Answer 16

Measures intenisy, visually

Question 17

What is richter scale measures in?

Answer 17

1-10

Question 18

What is the mercalli scale measured in?

Answer 18

1-12 in roman numerals

Question 19

How are volcanous and earthquakes formed?

Answer 19

By tectonic plates making large amount of pressure and it being released causing an earthquake. Volcanous are formed by lava seeping through cracks in earths surface

Question 20

what are convection currents and why are they important?

Answer 20

In mantle, lava/magma rises and it is able to go through the crust and find an entrance through the crust and make a volcano and an eruption.

Question 21

What happens at convergent boundries?

Answer 21

At Convergent boundries the curst is destroyed as one plate lives under another

Question 22

What happens at divergent boundries?

Answer 22

Where new crust is generated as the plates pull away from eachother?

Question 23

What happens at conservative plate boundries?

Answer 23

The crust is neither produced nor destroyed as the plates slide horizontally past eachother

Question 24

Primary impacts from Haiti earthquakes?

Answer 24

220,000 people killed, 2million Haitians left without food and water, Hospitals and goverment buildings destroyed,100,000 houses destroyed, 4,000 inmates escaped prison1.3mill homeless

Question 25

Secondary impacts of Haiti earthquake?

Answer 25

Poverty levels risen 80%, frequent power cuts, bodies stuck under buildings and disease spread, many roads blocked

Question 26

Physical factors on why Haiti earthquake was so bad?

Answer 26

Epicentre middle of city, focus near surface, magnitude high(6.9), itensity 9

Question 27

Human factors on why haiti earthquake

Answer 27

Level of development low, low life expenctancy, low internet uses, high level of poverty, buildings standards low, high unemployment, goverment debt (4.5bill), population 10m

Question 28

How are tsunamis triggered?

Answer 28

By earthquakes under sea.

Question 29

Example of tsunami and what plates and what happened

Answer 29

2004 26th Decemeber- Indian Ocean Tsunami
1)Indo-Australlian plate subducts and Euroaisan plate stuck
2) earthquake occurs and water displaced vertically from epicentre
3) Waves low and fast (500mph) as approch shallow water slow down and grow taller and converge togther, called wave amplication.
4) Affected 12 countries
5) Waves 20-30m

Question 30

How do you make a building earthquake proof?

Answer 30

Cross bracing, steel frames, controlled eights kn roof to reduce movement, fire-resistant building materials, automatic window shutters, rubbber shock absorbers

Question 31

How do you prepare for an earthquake?

Answer 31

Drop to the floor,conver yourself with table or desk, hold on to it firmly