Hazardous Earth - Plate Boundaries and hotspots

Question 1

What are the 3 types of plate boundaries

Answer 1

(1) Convergent
(2) Divergent
(3) Conservative

Question 2

How do plates move in convergent - give examples and name the hazards

Answer 2

they collide - one plate flows beneath another (subduction)
Nazca and South American plates
Many earthquakes and volcanoes

Question 3

How do plates move in divergent - name the hazards

Answer 3

Rising convection currents pull crust apart forming volcano ridge - e.g. mid-Atlantic ridge
Eurasian and North American plates
- Volcanos

Question 4

How do plates move in conservative

Answer 4

Two plates slide past each other
San Andreas Fault
Earthquakes

Question 5

What are hotspots

Answer 5

Points on the earth’s crust with very high heat flow, which is linked to volcanic activity.
Not all are linked to plate boundaries eg Lanzarote

Question 6

Which of the plates would you not find volcanoes

Answer 6

Conservative

Question 7

Which of the plates would you not find earthquakes

Answer 7

Divergent

Question 8

what are the key differences between compositive vs shield volcanoes

Answer 8

(1) What they are made of - Andestitic magma (lower in temp, has more silica and lots of gases so will explode) vs Basaltic (high temp, low silica and low gas content - produces runny magma with little explosive activity
(2) Type of lava (Compositive - acidic lava - very sticky; Shield = basic lava which is non-acidic and very runny
(3) Shape (compositive steep sides; Shield gentle sides
(4) eruptions - Compositive - violent but infrequent; Shield = non violent but frequent
(5) Layers? Compositive - alternative layers of ash and lava - also called stratovolcaones - strat means layers ; Shield = no layers