| A | B |
|---|
| analyze | to examine in detail for a purpose |
| continent | any of Earth’s main continuous areas of land, such as Africa, Asia, and North America |
| convergent | moving toward the same place |
| cross section | a diagram that shows what the inside of something looks like |
| divergent | moving apart in different directions |
| earth quake | a sudden shaking of Earth’s surface |
| eruption | the sudden pushing out of something, such as lava from a volcano |
| fossil | evidence of life from the past, such as fossilized bones, footprints, or leaf prints |
| geyser | a natural spring that sends hot water and steam suddenly into the air from a hole in the ground |
| landform | a feature that forms on the surface of a planet, such as a mountain, channel, or sand dune |
| lava | hot liquid rock on the surface of Earth |
| magma | hot liquid rock below the surface of Earth |
| mantle | the layer of soft, solid rock underneath Earth’s plates |
| Mesosaurus | an extinct reptile that lived about 300 million years ago |
| mid-ocean ridge | an underwater mountain range formed when two plates move apart |
| model | an object, diagram, or computer program that helps us understand something by making it simpler or easier to see |
| outer layer | Earth’s outermost layer of hard, solid rock that is underneath the soil, vegetation, and water |
| pattern | something we observe to be similar over and over again |
| plate | one of the very large sections of hard, solid rock that make up Earth’s outer layer |
| plate boundary | the place where two plates meet |
| rate | how often or fast something happens |
| rifting | the slow pulling apart of land that is caused by plate movement |
| surface | the outside or top layer of something |
| system | a set of interacting parts forming a complex whole |
| trench | a long, deep indentation in the ocean floor formed when two plates move together |
| volcanic activity | any of the many processes (such as eruptions and lava flows) in which gas, lava, and ash are pushed out on the surface of Earth |
