Who proposed continental drift?
Alfred Wegener
Who mapped the ocean floor using sonar?
Harry Hess
Which layer is rigid and broken into plates?
Lithosphere
What boundary forms deep ocean trenches?
Convergent
Point directly above an earthquake focus?
Focus
What was the supercontinent called? What two continents were formed millions of years later?
Pangaea
Gondwana and Laurasia
What underwater feature marks the site of new crust formation?
Ocean ridge
What layer allows plates to glide?
Asthenosphere
What crust type always subducts?
Oceanic
What scale measures earthquake magnitude?
Richter scale
What mineral records magnetic polarity?
Magnetite
What symmetrical pattern forms beside ocean ridges?
Magnetic stripes/ stripping
What causes hot mantle material to rise?
Heat from the Earth's core
What feature forms when two continental plates collide?
Creates mountain ranges
What is indicated by the letter B?
Lag time
What matched outlines supported continental drift?
Continents coast lines
On a topographical map, the mid-Atlantic ridge is indicated by what colour? Blue, green or red?
Green
What mechanism ultimately moves tectonic plates?
Convection currents
What is the name given to the volcanic ash and rock that comes out of a volcano during an eruption?
Pyroclastic flow
Which part of the seismogram pictured above can travel through liquids and solids?
A
What geological process begins when the crust stretches and cracks apart?
Rifting
What term describes the uplifted volcanic region at spreading centres?
Ridging
How many major continental plates are there?
7
Where do most volcanoes occur, and around which tectonic plate
Ring of fire - Pacific plate
Where was the largest ever recorded earthquake in history and what was its magnitude?
Chile - 9.5