4. The supercontinent which formed at the end of the Paleozoic Era and began breaking up about 200 million years ago to form today's continents.
5. A dating method that uses measurements of certain radioactive isotopes to calculate the ages in years (absolute age) of rocks and minerals.
7. An upward-curving (convex) fold in rock that resembles an arch. (The central part contains the oldest section of rock)
10. The theory that the Earth's outer shell is made up of about a dozen lithospheric plates that move about and interact at their boundaries.
14. A fracture in the Earth along which one side has moved in relative to the other. Sudden movements along these features cause earthquakes.
15. General term for folding, faulting, and other processes resulting from shear, compression, and extension of rocks
16. Rock that has undergone chemical or structural changes produced by increase in heat or pressure, or by replacement of elements by hot, chemically active fluids.
17. A usually asymmetrical hill of wind-deposited sand.
18. Any break in rock along which no significant movement has occurred.
20. A mineral deposit that can be mined at a profit
1. A dating method that places rocks and geologic structures in the correct chronological order.
2. Rocks that are formed from preexisting rocks or pieces of once-living organisms.
3. The innermost layer of the Earth, made up of mostly of iron and nickel.
6. The rocky, relatively low density, outermost layer of the Earth.
8. An area of concentrated heat in the mantle that produces magma that rises to the Earth's surface to form volcanic islands. The volcanic activity of the Hawaiian Islands is one example.
9. Rock formed when molten rock (magma) has cooled and solidified (crystallized).
11. The conversion of loose sediment into solid sedimentary rock.
12. Removal of material by water, wind, or ice.
13. A natural opening in the ground extending beyond the zone of light and large enough to permit the entry of an average human.
19. The solid rock that lies beneath soil and other loose surface materials.