| A | B |
|---|
| How do volcanoes form at converging boundaries? | One plate moves under the other and melts, forming magma. The magma is less dense than rock, and rises to the surface. |
| Where do we find volcanoes formed at converging boundaries? | Pacific NW United States |
| How do volcanoes form at diverging boundaries? | Ocean plates pull apart, magma flows out of the cracks in the ocean floor. |
| How do "hot spots" form volcanoes? | Magma formed in the mantle rises and breaks through the crust. |
| Give an example of a hot spot volcano. | Hawaiian Islands |
| The long tube in the ground that connects the magma chamber to Earth's surface | pipe |
| Volcano made of many layers of thin, runny lava that has built up a high, level area | shield |
| lava that has not yet reached the surface | magma |
| magma that has reached the surface | lava |
| What does the force of stress add to rock? | Energy |
| Stress that pushes a mass of rock in two opposite directions | tension |
| A fold in rock that bends upward into an arch (think "angel") | anticline |
| A fold in rock that bends downward (think "sinner") | syncline |
| speed of surface waves, compared to P and S waves | slower |
| P waves move ________ than S waves | faster |
| The scale used to rate the amount of damage done by an earthquake in a given place. | Mercalli scale |
| A device that uses wire stretched across a fault to measure horizontal movement of the ground | creep meter |
| A device that measures vertical movement of the ground, like a carpenter's level | tilt meter |
| measures both horizontal and vertical movement along a fault | GPS |
| rating system that estimates the total energy released by an earthquake | moment magnitude scale |
| A large area of flat land elevated high above sea level | plateau |
| A pyroclastic flow typically occurs during this type of eruption. | explosive |
| A volcano that is erupting or about to erupt | active |
| a volcano that hasn't erupted for a while, but may in the distant future | dormant |
| a place in the side of a volcano where magma may force its way out | vent |
| The first seismic waves to arrive | P waves |
| rocks on either side of this fault slip past each other sideways | strike-slip |
| type of boundary found along a mid-ocean ridge | diverging |
| what a seismograph records | ground movements caused by seismic waves |
| volcano formed by ash, cinders and bombs building up in a steep pile around the vent | cinder cone |
| main hazard of a quiet volcanic eruption | lava flows |
| rocky particles about the size of a grain of sand | volcanic ash |
| location of volcanic belts | boundaries of Earth's plates |
| pumice is most likely formed in what kind of eruption? | explosive |
| What does the upward flow of magma before a volcanic eruption often trigger? | earthquakes |
| direction of seismic waves | away from the focus |
| earthquake waves that can travel through both liquids and solids | P waves |
| a force that acts on rock to change its shape or volume | stress |
| What will likely happen wherever plate movements store energy in the rock along faults? | earthquakes |
| point beneath Earth's surface where rock breaks and triggers and earthquake | focus |
| point on Earth's surface directly above the focus of an earthquake | epicenter |
| The land between two normal faults moves upward to form a | fault-block mountain |
