| A | B |
|---|
| geologist | scientist who studies the earth's structure |
| bedrock | solid, unmovable rock below the earth's crust |
| magma | melted or molten rock |
| lava | magna that has erupted from the earth |
| weathering | process of breaking down rock |
| natural resource | any useful material found on earth |
| humus | decaying plant and animal material |
| mineral | building blocks of crystals |
| crystal | a shapely formation with flat surfaces and sharp edges |
| geode | rock-like object made of crystal formations |
| gemstone | rare, beautiful minerals |
| mineralogist | scientist who studies minerals |
| stalactite | rock formations on the ceiling of caves |
| stalagmite | rock formations on the floor of caves |
| petroleum | oil in its natural state (crude oil) |
| coal | rock-like substance used for fuel |
| fossil | plant and animal remains preserved in stone |
| paleontologist | scientist who studies fossils |
| geyser | underground spring that shoots water and steam into the air |
| spelunker | a cave exxplorer |
