Exam II

Question 1

aa (type of lava)

Answer 1

Consists of angular chunks of lava

Question 2

caldera

Answer 2

A large crater typically formed by a large volcanic eruption at the mouth of the volcano.

Question 3

cinder cone

Answer 3

Cinder cones are the simplest type of volcano. They are built from particles and blobs of congealed lava ejected from a single vent. As the gas-charged lava is blown violently into the air, it breaks into small fragments that solidify and fall as cinders around the vent to form a circular or oval cone.

Question 4

crater

Answer 4

You know what a crater is

Question 5

diatreme

Answer 5

a long vertical pipe or plug formed when gas-filled magma forced its way up through overlying strata.

Question 6

fissure

Answer 6

a long, narrow opening or line of breakage made by cracking or splitting, especially in rock or earth.

Question 7

flank collapse

Answer 7

Caused by magma trying to push out of an already weakened, steep volcanic wall. Extremely destructive.

Question 8

flood basalt

Answer 8

A flood basalt is the result of a giant volcanic eruption or series of eruptions that covers large stretches of land or the ocean floor with basalt lava.

Question 9

basalt lava

Answer 9

molten rock enriched in iron and magnesium and depleted in silica

Question 10

fumarole

Answer 10

an opening in or near a volcano, through which hot sulfurous gases emerge.

Question 11

Geyser

Answer 11

a hot spring in which water intermittently boils, sending a tall column of water and steam into the air.

Question 12

hydrothermal activity

Answer 12

Hydrothermal activity simply refers to the movement of heated water, usually beneath the surface of the earth

Question 13

lahar

Answer 13

a destructive mudflow on the slopes of a volcano. Can occur when pryoclastic flow meets a river or a snow bank. very dangerous. very bad.

Question 14

large igneous province

Answer 14

A large igneous province (LIP) is an extremely large accumulation of igneous rocks, including intrusive (sills, dikes) and extrusive (lava flows, tephra deposits), arising when magma travels through the crust towards the surface.

Question 15

lava dome

Answer 15

a lava dome is a circular mound-shaped protrusion resulting from the slow extrusion of viscous lava from a volcano

Question 16

pahoehoe

Answer 16

basaltic lava forming smooth undulating or ropy masses.

Question 17

pillow basalt

Answer 17

pillow-like rocky masses formed by lava

Question 18

pyroclast

Answer 18

sedimentary rock formed primarily by volcanoes

Question 19

pyroclastic flow

Answer 19

a dense, destructive mass of very hot ash, lava fragments, and gases ejected explosively from a volcano and typically flowing downslope at great speed.

Question 20

shield volcano

Answer 20

a broad domed volcano with gently sloping sides, characteristic of the eruption of fluid, basaltic lava

Question 21

stratovolcano

Answer 21

A stratovolcano, also known as a composite volcano, is a conical volcano built up by many layers of hardened lava, tephra, pumice and ash

Question 22

vent

Answer 22

an opening, as in a wall, serving as an outlet for air, smoke, fumes, or the like. an opening at the earth’s surface from which volcanic material, as lava, steam, or gas, is emitted.

Question 23

volcanic ash

Answer 23

Volcanic ash consists of fragments of rock, minerals, and volcanic glass, created during volcanic eruptions and measuring less than 2 mm (0.079 inches) in diameter

Question 24

volcanic bomb

Answer 24

A volcanic bomb is a mass of molten rock (tephra) larger than 64 mm (2.5 inches) in diameter, formed when a volcano ejects viscous fragments of lava during an eruption. They cool into solid fragments before they reach the ground.

Question 25

volcano

Answer 25

A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. Earth's volcanoes occur because its crust is broken into 17 major, rigid tectonic plates that float on a hotter, softer layer in its mantle.

Question 26

If the sample has more daughter, it is

Answer 26

younger

Question 27

If the sample has more father, it is

Answer 27

older

Question 28

Time scale

Answer 28

Eons > Eras > Periods > Epochs

Question 29

First 3 Eons

Answer 29

Precamprian time First: Hadean Eon Second: Archean (Arche=beginning) Third: Proterozoic (proteros=first, zoion=animal)

Question 30

4th Eon

Answer 30

Phanerozoic

Question 31

Describe the nature and location of magma chambers.

Answer 31

Typically in shallow depths in the crust, empties through a feeder and into a central vent causing eruptions.

Question 32

andesitic lava

Answer 32

higher silica content than basaltic lava, lower, and flows slowly in clumps.

Question 33

rhyolitic lava

Answer 33

richest in silica, most viscous lava type, typically erupts in pretty pink color. high in sodium and potassium.

Question 34

Spatter cone volcano

Answer 34

Steep sided and low mounds formed of lava fragments that form a linear fissure. Very irregular shapes.

Question 35

Complex volcano (compound)

Answer 35

formed when there is a change in the eruptive nature of the volcano or a main vent aarea.

Question 36

Fissure eruption location

Answer 36

typically along mid-ocean ridges

Question 37

Abrasion

Answer 37

physical erosion caused by water movement and particles inside the water.

Question 38

Frost wedging

Answer 38

freezing and thawing

Question 39

Volcanic gases

Answer 39

vapor (H2O), carbon dioxide (CO2), sulfur either as sulfur dioxide (SO2) (high-temperature volcanic gases) or hydrogen sulfide (H2S) (low-temperature volcanic gases), nitrogen, argon, helium, neon, methane, carbon monoxide and hydrogen.

Question 40

How do volcanoes affect the climate

Answer 40

Most of the particles spewed from volcanoes cool the planet by shading incoming solar radiation. The cooling effect can last for months to years depending on the characteristics of the eruption.

Question 41

Benefit of volcanoes

Answer 41

provides nutrients for nearby soil.