earthquake/volcano vocabulary

Question 1

Ring of Fire

Answer 1

The Ring of Fire is a region around much of the rim of the Pacific Ocean where many volcanic eruptions and earthquakes occur.

Question 2

Strike-slip fault

Answer 2

A fault on which the two blocks slide past one another. The San Andreas Fault is an example of a right lateral fault.

Question 3

Normal fault

Answer 3

A dip-slip fault in which the block above the fault has moved downward relative to the block below.

Question 4

Reverse fault

Answer 4

In a reverse fault, the block above the fault moves up relative to the block below the fault.

Question 5

P-waves

Answer 5

A P wave, or compressional wave, is a seismic body wave that shakes the ground back and forth in the same direction and the opposite direction as the direction the wave is moving.

Question 6

S-waves

Answer 6

An S wave, or shear wave, is a seismic body wave that shakes the ground back and forth perpendicular to the direction the wave is moving.

Question 7

Epicenter

Answer 7

The central point of an earthquake is an example of an epicenter.

Question 8

Focus

Answer 8

The definition of a focus is the central point of attention. An example of focus is a newborn baby in a family.

Question 9

Richter magnitude scale

Answer 9

The Richter magnitude scale, also known as the local magnitude (M) scale, assigns a number to quantify the amount of seismic energy released by an earthquake.

Question 10

Explosive volcano

Answer 10

A Pelean eruption is associated with explosive outbursts that generate pyroclastic flows, dense mixtures of hot volcanic fragments and gas described in the section Lava, gas, and other hazards.

Question 11

Nonexplosive volcano

Answer 11

Nonexplosive eruptions are the most common type of volcanic eruptions.

Question 12

Krakatoa

Answer 12

Krakatoa is a small volcanic island in Indonesia, located about 100 miles west of Jakarta. In August 1883, the eruption of the main island of Krakatoa (or Krakatau) killed more than 36,000 people, making it one of the most devastating volcanic eruptions in human history.

Question 13

Yellowstone supervolcano

Answer 13

The Yellowstone Caldera, sometimes referred to as the Yellowstone Supervolcano, is a volcanic caldera and supervolcano in Yellowstone National Park in the Western United States.

Question 14

San Andreas fault

Answer 14

The San Andreas Fault is a continental transform fault that extends roughly 1,200 kilometers through California.

Question 15

Mid-oceanic ridge

Answer 15

The mid-ocean ridge is a continuous range of undersea volcanic mountains that encircles the globe almost entirely underwater.

Question 16

Shield volcano

Answer 16

Where a volcano produces low viscosity, runny lava, it spreads far from the source and forms a volcano with gentle slopes: a shield volcano. Most shield volcanoes are formed from fluid, basaltic lava flows. Mauna Kea and Mauna Loa are shield volcanoes.

Question 17

Cinder cone volcano

Answer 17

A cinder cone (or scoria cone) is a steep conical hill of loose pyroclastic fragments, such as volcanic clinkers, volcanic ash, or cinder that has been built around a volcanic vent.

Question 18

Composite volcano

Answer 18

They form when different types of eruptions deposit different materials around the sides of a volcano.

Question 19

Hot spot

Answer 19

A hot spot is an area on Earth over a mantle plume or an area under the rocky outer layer of Earth, called the crust, where magma is hotter than surrounding magma.

Question 20

Mt. Vesuvius

Answer 20

Mount Vesuvius is a somma-stratovolcano located on the Gulf of Naples in Campania, Italy, about 9 km east of Naples and a short distance from the shore.