| A | B |
|---|
| seamount | underwater volcano |
| surface waves | combination of up and down and back and forth motion |
| destruction | surface waves cause more of this than other waves |
| ring of fire | zone of volcanic activity in Pacific |
| mantle plumes | mushroom shaped trails of hot magma |
| longitudinal wave | compresses earth's crust in front and stretches crust in back of it |
| tectonic plate boundaries | where earthquakes occur |
| three | number of seismograph stations needed to determine the earthquake's epicenter |
| seismograph | measures how much of the earth moves during an earthquake |
| seismic | when rocks break along a fault line they release energy in the form of these waves |
| volcano | opening in earth's crust through which magma has reached the earth's surface |
| seamount | underwater volcano |
| shield volcano | mild eruption produce a gently sloping mountain, magma rich in iron and magnesium |
| composite volcano | alternating layers of ash, cinders and lava |
| cinder cone | smallest, most abundant volcanoes |
| minerals | what rocks are composed of |
| igneous | rocks formed from cooled molten rock |
| weathering | process by which rocks are broken down |
| sedimentary | rocks formed from compressed layers of sediment |
| igneous | type of rock granite is |
| metamorphic | rocks changed by heat and/or pressure without melting |
| principle of superposition | oldest rocks on the bottom, younger rocks on top |
| age | what we learn from position of rock in layers |
| physical weathering | breaks rocks into smaller pieces |
| chemical weathering | when rocks react with other materials, such as acid rain |
| acid rain | formed when carbon dioxide dissolves in rainwater |
| deposition | process of depositing sediment |
| erosion | process of loosening and moving sediments |
| water | Main agent of physical weathering and erosion |
| marble | metamorphic rock that was limestone |
| slate | metamorphic rock that was shale |
