Plate Tectonics & the Earth's structure Flashcards
1
Q
what was Wegener’s theory?
A
- though that the contents would fit together like a jigsaw if put together
- believed the continents previously had been one continent which then split up
2
Q
why wasn’t Wegener’s theory accepted for years?
A
- ## scientists thought that it was impossible that continents and their movement was caused by tidal forces
3
Q
why was Wegener’s theory convinced to be true by the 1960’s?
A
- several chunks called tectonic plates that move about
- colliding chunks move about and push up land to create mountains
4
Q
what are the features of the earth from the outside in?
A
- crust
- mantle
- outer core
- inner core
5
Q
what happens in the mantle?
A
radioactive decay take places. makes heat which causes convection currents
6
Q
what do we think the core of the earth is made of?
A
nickel and iron
7
Q
what is the earth’s surface made up of?
A
tectonic plates
8
Q
what causes the plates to drift?
A
convection currents
9
Q
how do earthquakes occur?
A
when the plates move suddenly
10
Q
where do volcanoes and earthquakes take place?
A
occur at the boundaries between 2 tectonic plates
11
Q
are we able to predict earthquakes and volcanic eruptions?
A
no
