Earth Flashcards
Describe the composition of the geosphere.
Crust- a thin layer of light surface rock, which covers one third of the surface and forms the continents.
Mantle- solid rock but intensely hot. It is under such high pressure that hotter parts may actually flow as cove toon currents.
The central core- is thought to be mainly metals, very dense and extremely high temperatures. The inner part is solid and outer molten liquid.
Name the spheres of the earth and what the are?
Atmosphere- extends up from the earths surface for several hundred kilometers. The lower part has our weather.
Geosphere- includes all minerals, rocks, sediments and soil.
Hydrosphere- includes all the ocean, rivers, lakes, streams, snow, glaciers and ice.
Biosphere- all living things on earth.
Name the 8 main plates. And the to that nz sit on.
North American South American Nazca Pacific Eurasian African Indo-Australian Antarctica Nz sits on both indo-Australian and pacific
Volcanoes happen because…
Hot molten rises and splits an area of the tectonic plate causing molten lava to explode through the earth
Earthquakes happen because…
Plates moving past each other cause immense pressure, when the stress is greater than what the rock can handle it splits and slides past each other causing an earthquake.
What causes mountain ranges?
Where two continental plates crash into each other causing it to push up into a mountain
What are p-waves
S-waves and L-waves?
P-waves are the primary waves which compress and stretch rock.
Damage level minor.
S-waves are secondary waves which shake rock up down and sideways. Damage level moderate.
L-waves can make the ground roll in waves. Damage level is major.
What is a subduction zone?
Area where one plate moves under an overriding plate
New Zealand landmarks
Marlborough sounds- drowned river valleys
Mountain alpine range
Terraces
Red hills/ Dunn hills
What are river valleys and how are they formed?
The are v shaped valleys, caused by erosion and weathering.
What is a fiord and how is it formed?
A fiord is a u shaped valley and is caused by glaciers.
What is physical weathering?
Solid Rick is vulnerable to physical weathering. Hot days and freezing nights cause rock to expand. Then contract and eventually crack. When water enters cracks and freezes it expands and cracks.
What is chemical weathering?
When water enters cracks and starts to react with the minerals in the rock, chemical weathering occurs, the new chemical may be soluble which will help speed up the disintegration of the rock.
What is erosion?
The final process of the final deposition(settling) of the debris on the sea floor.
What is the 3 ways tectonic plates move?
Collision zone- when the plates push into each other.
spreading zone - when the plates move apart and creating new material.
transform fault - moving sideways past each other.
