Terms : Hide Images
| 12219664609 | geologic time scale | scale used by paleontologists to represent evolutionary time |  | 0 |
| 12219674726 | core | Center of the earth (inner and outer) |  | 1 |
| 12219728233 | mantle | the layer of the earth between the crust and the core | 2 | |
| 12219728410 | athenosphere | The soft layer of the mantle on which the tectonic plates move | 3 | |
| 12219728683 | lithosphere | A rigid layer made up of the uppermost part of the mantle and the crust. |  | 4 |
| 12219729320 | crust | Earth's outermost layer (also part of the lithosphere) |  | 5 |
| 12225965671 | pangaea | large, ancient landmass that was composed of all the continents joined together |  | 6 |
| 12225971566 | tectonic plates | Large movable plates under the Earth's surface (~12 plates, and plates are made out of mantle/crust) |  | 7 |
| 12225988637 | plate boundaries | the edges of tectonic plates | 8 | |
| 12225995861 | convergent boundary | A tectonic plate boundary where two plates collide, come together, or crash into each other |  | 9 |
| 12225999395 | divergent boundary | The boundary between two tectonic plates that are moving away from each other |  | 10 |
| 12225999789 | magma | Molten rock beneath the earth's surface |  | 11 |
| 12226064297 | basaltic | Igneous rock composed mostly of dark colored, dense, minerals containing compounds of iron and magnesium |  | 12 |
| 12226067781 | rhyolitic | high silica composition, high gas content, result of explosions |  | 13 |
| 12226084067 | pyroclastic flow | The expulsion of ash, cinders, bombs, and gases during an explosive volcanic eruption |  | 14 |
| 12226120185 | transform fault boundary | an area where tectonic plates move sideways past each other |  | 15 |
| 12226121131 | volcanoes | an opening in the Earth's crust through which molten lava, ash, and gases are ejected (magma = volcano) |  | 16 |
| 12226121949 | active volcanoes | Are currently erupting or show sign of erupting in the near future |  | 17 |
| 12226122522 | dormant volcano | A volcano that has not erupted for a long time, but may erupt again one day |  | 18 |
| 12226122806 | extinct volcano | A volcano that has not erupted for thousands of years and probably will not erupt again |  | 19 |
| 12226123950 | rift valley | a valley formed by the separation of tectonic plates |  | 20 |
| 12226125001 | subduction zones | places where plates are pushed down into the upper mantle |  | 21 |
| 12226125418 | hot spots | places where molten material from the mantle reaches the lithosphere |  | 22 |
| 12226126014 | shield volcanoes | broad base, gentle slopes, oceanic hot spot, mild eruption, slow lava flow. if contact w h20 occurs then it can lead to a pyroclastic flow |  | 23 |
| 12226127607 | composite volcanoes | broad base, steeper slope, subduction zones, violent eruptions, lava, water, gases, super heated ash and stones |  | 24 |
| 12226129138 | cider volcano | a volcano that formed when molten lava erupts and cools quickly in the air (hardening into rock) |  | 25 |
| 12226132082 | earthquakes | a sudden and violent shaking of the ground, sometimes causing great destruction, as a result of movements within the earth's crust or volcanic action. |  | 26 |
| 12226133260 | focus | Point at the depth where the rocks ruptured to produce earthquakes; place where quake waves originate |  | 27 |
| 12226133467 | epicenter | Point on Earth's surface directly above an earthquake's focus |  | 28 |
| 12226133847 | seismograph | A device that records ground movements caused by seismic waves as they move through Earth |  | 29 |
| 12226134399 | S waves | A type of seismic wave that moves the ground up and down or side to side |  | 30 |
| 12226134837 | richter scale | A scale that rates an earthquake's magnitude based on the size of its seismic waves. |  | 31 |
