Earth and Geological changes

1. The circulation of particles within a material caused by differences in thermal energy and and density.
4. A German scientist that proposed the continental drift hypothesis.
5. The process that results when a dense oceanic plate sinks beneath a more buoyant plate along a subduction zone, pulling the rest of the plate that trails behind it.
10. The process by which new oceanic crust forms along a mid-ocean ridge and older oceanic crust moves away from the ridge.
11. The boundary between two plates that move toward each other.
12. Name given to a supercontinent that began to break apart approximately 200 million years ago.
13. When the magnetic field reverses direction.
17. A type of rock that forms when lava cools.
20. The boundary between two plates that move away from each other.

2. A state in which magnetized objects will orient themselves to point north.
3. The process that results when magma rises at a mid-ocean ridge and pushes oceanic plates in two different directions away from the ridge.
6. Wegener's hypothesis which suggested that the continents are in constant motion on Earth's surface.
7. The boundary between two plates that slide past each other.
8. Magma on Earth's surface.
9. A state in which magnetized objects will orient themselves to point south.
14. The rigid outermost layer of Earth that includes the uppermost mantle and crust.
15. Mountain ranges in the middle of the ocean.
16. Used to measure and record the magnetic signature of rocks.
18. The layer of sediment that becomes thick enough to make the seafloor smooth.
19. The process that occurs when one tectonic plate moves under another tectonic plate.