Planet Earth and Processes Flashcards
How is the earths magnetic field generated?
The liquid metal outercore flows over the earths inner core, this interaction generates earth’s magnetic field.
What is the magnetosphere and why is it important?
The magnetosphere is the earth’s magnetic field sheilding earth, it deflects solar wind from, the sun away from the earth - stops huge radiation from affecting the earth.
What’s earths atmosphere made out of?
78% Nitrogen and 21% Oxygen
What’s the stratosphere?
This is where the ozone is located.
What are volitiles?
These are materials which turn in to gas at the surface - these are released during volcanic eruptions.
What is the moho effect?
This is how we know the earth has layers, this is when seismic waves change their velocities with density. As the earths interier layers change with density, we can determine the earth’s layers via studying the changes in velocity.
What’s oceanic crust made from and how is this made?
The balsic oceanic crust is made through a process called sea floor spreading.
What’s the mantle made from?
It’s made entirely of peridotite.
What is the continental crust made from in compostion?
It’s made from granite in composition.
What is the composition of the earth’s layers?
Crust - solid
Mantle - Solid rock, hot rises, cold sinks - here is where we have convection currents.
The Outer Core - liquid (iron and nickel) the covection of this causes the earth’s magnetic field.
The inner Core- It’s made from iron and nickel - Solid.
What is the Lithosphere?
This is the outermost 100km - 150km of earth - this is the crust and upper mantle, it also makes up the tectonic plates.
What is the asphenosphere?
This makes up the upper mantle below the lithosphere, flows like a soft solid and it’s shallow under the oceanic lithosphere, deeper under the continental.
