| Question | Answer |
| Elastic rebound | the sudden return of elastically deformed rock to its undeformed shape. |
| viscosity | the resistance to flow of a fluid. describes how sticky or runny magma is. |
| Understand how the Modified Mercalli scale is used to measure an earthquake’s intensity. | The Modified Mercalli scale expresses intensity in Roman numerals from I (one) to XII (twelve). The bigger the value, the more damage that was caused by the earthquake. |
| caldera | a large, circular depression that forms when the magma chamber below a volcano partially empties and causes the ground above to sink |
| subduction zones | form at a convergent plate boundary when the more dense oceanic crust slides beneath the less dense continental crust |
| Seismogram | A tracing of earthquake motion that is recorded by a seismograph. |
| Seismograph | The machine that records vibrations (seismic waves) during an earthquake. |
| evidence of the boundries | earthquakes and volcanoes |
| cinder cone | very small, steep volcanoes made from small eruptions of pyroclastic material |
| Intensity | a measure of the damage caused by an earthquake |
| formation of the hawaiian islands | pacific plate moving over a stationary mantle plume. as the plates slide magma comes up through the ocean floor and conditionally builds a volcano until it breaches the oceans surface and becomes an island |
| pyroclastic material | fragments that form an explosive volcanic eruption |
| lava | magma that flows onto earths surface; the rock that forms when lava cools and solidifies |
| Understand how earthquake warnings and forecasts can be developed. | Scientists study past earthquakes in a region to make approximate forecasts about future earthquakes. Instruments along fault zones can detect small changes in rock movement and an increase in stress. |
| Understand how an earthquake can affect buildings and property | Earthquakes can cause buildings to sway and topple over, or to collapse. Things like roads and bridges can be torn apart. Buildings constructed in earthquake-prone areas are usually built with features that make them better able to withstand the shaking. |
| Magnitude | a measure of the strength of an earthquake. |
| ring of fire | a zone of active volcanoes surrounded the Pacific Plates |
| characteristics of mid ocean ridge | sediment was thinner closer to the center of the ridge, rocks were younger closer to the center of the ridge |
| Understand how the depth of focus affects an earthquake’s intensity. | With all other factors being equal, the deeper the focus (farther below ground), the lower the intensity, and the shallower the focus (closer to the surface), the greater the intensity. |
| mid-ocean ridge | A long undersea mountain chain that has a steep narrow valley at its center that forms as magma rises from the asthenosphere and that creates new oceanic lithosphere as tectonic plates move apart. |
| felsic | describes magma or igneous rock that is rich in feldspar and silica and that is generally light in color. comes from melted continental crust |
| magma | liquid rock produced under earth´s surface |
| vent | the opening of a valcano |
| transform boundary | the boundary between tectonic plates that are sliding past each other horizontally |
| Tsunami | a giant ocean wave that forms after a volcanic eruption, submarine (under water) earthquake, or landslide. |
| shield volcanoes | broad at the base with gently sloping side |
| Fault zone | a region of numerous, closely spaced faults. (Ex: North Anatolian fault zone in Turkey.) |
| examples of plate boundaries | divergent, convergent, and transform |
| seismic gap | an area along a fault where relatively few earthquakes have occurred recently, but where strong earthquakes are known to have occurred in the past. |
| composite volcanoes | alternating layers of lava and pyroclastic material |
| Understand how stress builds up along a fault and gets released. | When tectonic plates push up against each other, or try to slide past each other, stress builds up along the fault. Friction keeps the plates from moving until that force is overcome and the plates spring into their new position through elastic rebound |
| evidence for continental drift | fossil plant in Antarctica, mountain matched, similar coastlines |
| Who proposed hypothesis of continental drift | Albert Wegener |
| fissure | a crack through which lava flows to earths surface |
| Understand the difference between the Richter scale and the Moment Magnitude scale for measuring an earthquake’s magnitude. | Richer scale is base on ground motion only. The Moment Magnitude scale is based on the area of the fault that moved, the distance the fault blocks moved, and the rigidity of the rocks in the fault zone. |
| Seismic waves | energy released in the form of vibrations as rocks along a fault slip into new positions. |
| asthenophere | the solid plastic layer of the mantle beneath the lithosphere |
| convergent boundary | the boundary between two plates that are colliding |
| Know where earthquakes are most likely to happen. | Earthquakes are most likely to happen along a transform plate boundary. Earthquakes are very common around the Ring of Fire |
| number of major tectonic plates worldwide; name of our tectonic plate | 15; north american plate |
| lithosphere | the solid outer layer of earth that consists of the crust and the ridge upper part of the mantle |
| which events may signal an impending eruption | swarm of small earthquakes, increased gasses or small plumes of ash, ground inflation, changes in the slope of the volcanoes flank |
| sea-floor spreading | the process which new oceanic lithosphere forms when magma rises to earths surface at mid ocean ridges and solidifies as older existing sea-floor moves away from the ridge |
| divergent boundary | the boundary between tectonic plates that are moving away from each other |
| mafic | describes magma or igneous rock that is rich in magnesium and iron that is generally dark in color. comes from melted oceanic crust |
| Understand what people should do before, during and after an earthquake to be safe | If a person lives in an earthquake prone area, they should keep on hand a supply of canned food, bottled water, flashlights, batteries and a portable radio. |
| Focus | the location within the Earth along a fault at which the first motion of an earthquake occurs. |
| Continental drift | The hypothesis that a single large landmass broke up into smaller landmasses to form the continents which then drifted to there present locations. |
| hot spot | a volcanically active area of earths surface, commonly far from a tectonic plate boundary |
| Epicenter | the point on Earth’s surface directly above an earthquake’s starting point, or focus. |
