Different types of plate boundaries Changes in the position of continents
• Some plates are moving closer to each other – • All continents were once joined together – Pangaea.
convergent plate boundaries. • The continents moved apart due to continental drift.
• Some plates are moving further apart – divergent • Pangaea split into Laurasia and Gondwanaland.
plate boundaries. • Evidence – fossils, mountain ranges and ocean floor spreading.
• Some plates slide past each other at plate
boundaries – passive/transverse plate boundaries.
Plate tectonics
Landforms associated with • Heat rises from the mantle and breaks the crust into
different plate boundaries C2: Plate sections (tectonic plates) that move on the mantle.
Sample
• Folded mountain ranges - involves 2 continental
plates that collide and fold up which lifts the layers
of sedimentary rock which forms fold mountains.
tectonics • The currents form convection cells – at the top of
the cell, heat moves sideways and downwards.
• Ocean floor spreading and mid-oceanic ridges -
Summaries after sample
•
when 2 plates pull apart, magma rises and solidifies
at the surface.
Ocean trenches - occur along convergent plate
The world's volcanic and earthquake zones
boundaries where an oceanic plate converges with
a continental plate.
GR10 GEO T2-T3 Mind Map Focus Copyright © www.summariessa.co.za (DO NOT COPY)
, Structure of volcanoes Different kinds of volcanoes
Cinder cone volcano • Active volcanoes – still erupt.
• Dormant volcanoes – resting and haven’t erupted
• Built of fragments of cinders ejected from a single vent. for many years.
• Sends gas-charged lava into the air – breaks up and • Extinct volcanoes – haven’t erupted for very long
cools and falls to the ground as cinders and ash. and likely won’t ever again.
• .
Calderas
• When a volcano hasn’t erupted in a while, lava
builds up and solidifies in the crater.
C5: • When the volcano does erupt, an explosion occurs
Sample Volcanoes which pushes the lava ‘plug’ out and blows off the
top of the volcano – forms a caldera.
Summaries after sample
Shield volcano
• Lava flows from many vents.
•
Lava dome
Form from a small mass of viscous lava.
•
Composite volcano
Consists of alternating layers of ash,
cinders and lava.
• The lava doesn’t move far from the vent – • When the magma can’t reach the surface
• Lava cools into volcanic rock and more layers through the main crater, it’s forced
creates a bulbous shape.
form over it. through fissures (cracks) in the sides of the
volcano.
GR10 GEO T2-T3 Mind Map Focus Copyright © www.summariessa.co.za (DO NOT COPY)
,Sample
Summaries after sample
• Some plates are moving closer to each other – • All continents were once joined together – Pangaea.
convergent plate boundaries. • The continents moved apart due to continental drift.
• Some plates are moving further apart – divergent • Pangaea split into Laurasia and Gondwanaland.
plate boundaries. • Evidence – fossils, mountain ranges and ocean floor spreading.
• Some plates slide past each other at plate
boundaries – passive/transverse plate boundaries.
Plate tectonics
Landforms associated with • Heat rises from the mantle and breaks the crust into
different plate boundaries C2: Plate sections (tectonic plates) that move on the mantle.
Sample
• Folded mountain ranges - involves 2 continental
plates that collide and fold up which lifts the layers
of sedimentary rock which forms fold mountains.
tectonics • The currents form convection cells – at the top of
the cell, heat moves sideways and downwards.
• Ocean floor spreading and mid-oceanic ridges -
Summaries after sample
•
when 2 plates pull apart, magma rises and solidifies
at the surface.
Ocean trenches - occur along convergent plate
The world's volcanic and earthquake zones
boundaries where an oceanic plate converges with
a continental plate.
GR10 GEO T2-T3 Mind Map Focus Copyright © www.summariessa.co.za (DO NOT COPY)
, Structure of volcanoes Different kinds of volcanoes
Cinder cone volcano • Active volcanoes – still erupt.
• Dormant volcanoes – resting and haven’t erupted
• Built of fragments of cinders ejected from a single vent. for many years.
• Sends gas-charged lava into the air – breaks up and • Extinct volcanoes – haven’t erupted for very long
cools and falls to the ground as cinders and ash. and likely won’t ever again.
• .
Calderas
• When a volcano hasn’t erupted in a while, lava
builds up and solidifies in the crater.
C5: • When the volcano does erupt, an explosion occurs
Sample Volcanoes which pushes the lava ‘plug’ out and blows off the
top of the volcano – forms a caldera.
Summaries after sample
Shield volcano
• Lava flows from many vents.
•
Lava dome
Form from a small mass of viscous lava.
•
Composite volcano
Consists of alternating layers of ash,
cinders and lava.
• The lava doesn’t move far from the vent – • When the magma can’t reach the surface
• Lava cools into volcanic rock and more layers through the main crater, it’s forced
creates a bulbous shape.
form over it. through fissures (cracks) in the sides of the
volcano.
GR10 GEO T2-T3 Mind Map Focus Copyright © www.summariessa.co.za (DO NOT COPY)
,Sample
Summaries after sample
