L1 Flashcards
Describe the structure of the earth
Inner core (solid), outer core (liquid), Mantle (molten rock, liquid), Upper mantle/ Lithosphere (semi-solid),Crust (solid)
What the device used to measure radiation?
Geiger Counter
What feature of volcanos builds pressure leading to a more violent eruption?
A plug
What waves are used to measure how large each section of the earth is?
S waves and P waves.
What is the crust?
Top layer of Earth is a dry brittle surface of recently cooled lava
What are the two types of tectonic plates?
Oceanic and continental
What is the lithosphere?
The top of the mantle and all of the crust, together form the mantle.
What is the asthenosphere?
Then sticky, viscous, dense rock – slowly starts to move. This causes plate tectonics (The movement of plates)
What causes convection currents?
The temperature gradient in the mantle, as you get closer to the core, its hotter.
What is the Magnetosphere caused by?
Its produced by the spinning nickel and iron inner core, which produce a magnetic shield protecting the earth from solar radiation.
What are the 3 types of plate margins
Constructive, destructive, transform
What process usually causes the formation of a trench?
Subduction
Where and how is new land formed?
New land is formed at a divergent, constructive plate boundary, as the 2 plates move apart, the magma from below seeps up and dries to fill the gap.
What natural disaster often occurs at a transform plate margin?
Earthquakes
What is the asthenosphere?
The asthenosphere lies beneath the lithosphere and consists of partially molten rock. S waves passing through this layer are significantly slowed.
Name a constructive plate margin
The mid atlantic ridge
What landscape features are often found at convergent plate margins?
Trenches, Mountain Ranges
What happens to the subducted plate at a convergent plate margin?
The plate is driven down into the mantle where it melts into magama, then that magma fises up and will force its way out of a volcano.
Name a mountain range found at a convergent plate boundary.
The Andes mountains, the Himalayas
What substances change the viscosity of lava
Silica rich lava is erupted from more active volcanos and is a runny consistency
While granite rich is thick, causing violent eruptions from dormant volcanos
