1. Outline Alfred Wegener’s hypothesis of Continental Drift
Alfred Wegener believed all Earth’s continents were once joined together but gradually moved apart for millions of years by cracking and dividing due to slow currents of magna beneath it.
2. Cut out the attached Gondwana Jigsaw along the dotted lines. Fit the continents together and glue them in position. Hint, refer to other sheets for map.
3. Describe the evidence for Continental drift.
All the continents fit together much like puzzle pieces that have drifted apart. The same types of fossilised animals and plants can be found in both South America and Africa. Matching rock formations and mountain chains can be found in both South America and Africa.
4. Explain why Wegener’s hypothesis …show more content…
It makes up 40% of the Earth’s surface and has a density of 2.6 grams per centimetre cubed. It has a thickness of 35-70 kilometres.
Oceanic crust consists of dark coloured rocks made up of basalt known as mafic. Mafic is an igneous rock made of mainly magnesium and iron. Oceanic rock is also 7-10 kilometres thick. It has a density of 3 grams per centimetre cubed.
9. Define the terms subduction, mid-ocean ridge, and ocean trench and island arc.
Subduction is when two tectonic plate’s convergent boundaries come crashing together resulting in one going below the other. This results in the bottom plate to sink into the mantle.
Mid-ocean ridge is an underwater mountain ridge that forms when convection currents causes magma to rise where two tectonic plates meet at a divergent boundary.
Ocean trench are long narrow depressions on the sea floor as a result most ocean trenches form as a result of subduction but sometimes form because of asymmetry between the continental and oceanic boundaries
Island arc is a set of curved oceanic islands all with intense volcanic and seismic activities. It is formed by
Alfred Wegener believed all Earth’s continents were once joined together but gradually moved apart for millions of years by cracking and dividing due to slow currents of magna beneath it.
2. Cut out the attached Gondwana Jigsaw along the dotted lines. Fit the continents together and glue them in position. Hint, refer to other sheets for map.
3. Describe the evidence for Continental drift.
All the continents fit together much like puzzle pieces that have drifted apart. The same types of fossilised animals and plants can be found in both South America and Africa. Matching rock formations and mountain chains can be found in both South America and Africa.
4. Explain why Wegener’s hypothesis …show more content…
It makes up 40% of the Earth’s surface and has a density of 2.6 grams per centimetre cubed. It has a thickness of 35-70 kilometres.
Oceanic crust consists of dark coloured rocks made up of basalt known as mafic. Mafic is an igneous rock made of mainly magnesium and iron. Oceanic rock is also 7-10 kilometres thick. It has a density of 3 grams per centimetre cubed.
9. Define the terms subduction, mid-ocean ridge, and ocean trench and island arc.
Subduction is when two tectonic plate’s convergent boundaries come crashing together resulting in one going below the other. This results in the bottom plate to sink into the mantle.
Mid-ocean ridge is an underwater mountain ridge that forms when convection currents causes magma to rise where two tectonic plates meet at a divergent boundary.
Ocean trench are long narrow depressions on the sea floor as a result most ocean trenches form as a result of subduction but sometimes form because of asymmetry between the continental and oceanic boundaries
Island arc is a set of curved oceanic islands all with intense volcanic and seismic activities. It is formed by