Everything Flashcards
(35 cards)
What is the order of the stucture of the Earth?
Crust, mantle, outer core, inner core
What was wengers plate tectonic theory?
Alfred Wegener proposed that countries were once joined together and had then moved apart. In fact he believed that all the continents were once joined together as one big land mass called Pangaea
What are two pices of evidence to supports wengers theory
One: jigsaw fit two: convection currents
What are the names and locations of major plates and plate boundaries?
Antaritic plate- Antartica African plate- Antartica Eurasian plate- most of Europe ans a bit of Russia
why earthquakes and volcanoes are often found at plate boundries?
The movement of faults at plate boundaries can provide a convenient pathway for magma to reach the surface.
What are convection currents?
Convection currents are heat-driven cycles that occur in the air, ocean, and mantle. They are caused by a difference in temperature
How are earthquakes meausred?
Ritcher scale and Mercallie scale
What happens at convergent boundires?
At convergent plate boundaries where an oceanic plate meets a continental plate, oceanic crust is forced down into the Earth’s mantle and begins to melt
What happens at a divergent plate?
earthquakes are common and magma (molten rock) rises from the Earth’s mantle to the surface, solidifying to create new oceanic crust.
How are earthqukes formed?
Two plate move towards each other as a reslut of convenction current. The oceanic plate is more dense than the continetal plate so the oceanic sinks below. Huges amount of pressure occurs at the subdction zone and when the pressure is realsed a earthquake happens
How does volcanos happen?
Deep within the Earth it is so hot that some rocks slowly melt and become a thick flowing substance called magma. Since it is lighter than the solid rock around it, magma rises and collects in magma chambers. Eventually, some of the magma pushes through vents and fissures to the Earth’s surface.
What is the foucs of the earthquake?
the point in the earths crust where earthqukaes happen
What is the epicenter of the earthquake?
The point on the surface directly above the foucs
What boundries do earthqukes normmally happen on?
Earthsquakes normally happen on consevrstive and convergent plate boundires
What are continental plates?
theses are thicker and older and lighter so they dont subducts
What are ocenaic plate boundries?
theses are thinner and younger and more dense so they subdct when two meet
What happens at constructive plate boundires?
here the plates are moving apart from each other magma is fills the gap they made
What happens at destructive plate boundries?
the oceanic plate boundry subdcts under the continetal plate (the floor might shake)
What happens at conserative plate boundires?
At conserative plate margins plates slide past each other
In what year did Haiti earthquake happen
2010
What was a phycial feature of the Haiti earthquake?
There was a cinserative plate boundry running over Haiti
What were some the worst effects if the Haiti earthquake?
220,000 people died, 2 million people left without food and water and looting became a serious probelm
What are some human factors that made the Haiti earthquake so destructive?
buliding were not built properly and they didnt have enough funds for protection .
What is a active volcano?
A volcano which is liable to erupt
