Geo 1030 Quiz 10

Which of the following objects has a size similar to that of lapilli?

A marble (15 mm)

Lo'ihi

A new shield volcano called ________ is being formed just south of the island of Hawaii. It is still 3000 feet below the surface.

dome

A new volcanic _________ within the modified crater was produced during the 2004 Mt. St. Helens eruption.

How does the viscosity of the magma fed to volcanoes affect nearby life and property?

A volcano that expels highly viscous magma is a greater threat to life and property because it is more explosive and thus is more difficult or impossible to predict.

Yellowstone is best described as what?

An active volcano that has erupted in the last 1 million years

Yellowstone is best described as which of the following

An active volcano that has erupted in the last 1 million years

When Eyjafjallajökull erupted in March 2010, ash plumes drifted southeast over Europe and, as a result, the controlled airspaces over many European countries were closed to air traffic, stranding thousands of people worldwide. Why would flying a commercial jet through a cloud of volcanic ash be dangerous?

Ash impairs visibility, clogs engines, and abrades engine parts.

Philippine, Eurasian

At the Manila Trench, the _________ Plate is being subducted under the __________ Plate.

What kind(s) of lava generate a cinder cone?

Basalt

Shield volcanoes are generally made of ?

Basaltic flows

Massive pulton

Batholith

Batholiths are known to form the coves of mountain ranges such as Sierra Nevada implication of this observation

Because batholiths form deep in the Earth, the occurence of one at the surface implies that it has been uplifted and/or the rocks above have been removed

cinder cones

Black Rock Desert has smaller volcanoes called __________ _________.

Pyroclastic material ejected during a volcanic eruption composed of incandescent lava that is greater than 64 millimeters in diameter

Bombs

The majoruty of volcanoes are associated with which type pf tectoni plate boundary

COnvergent boundary

Which state has the greatest earthquake hazard

California

Which of the following is an extreme igneous feature associated with very violent eruptions? -Composite volcano -Cinder cone volcano -Shield volcano -Pahoehoe lava flow

Composite volcano

Types of volcanoes

Composite volcanoes. Cinder cone. Shield volcanoes.

What is the volcanic feature in which magma rises through before it is released at the surface?

Conduit

Which would best describe the shape and composition of a volcano in the cascade range

Cone shaped volcano with alternating layers of lava and pyroclastic materials

East African

Continental rifting is occurring in the __________ __________ Rift Valley, on the African continent. The region includes Mt. Kilimanjaro.

Convergent boundaries

Crater lake. Mt. st. Helens. Mt. Etnna, Italy.

Which stage in formation of yellowstone caldera

Crust bows upward above a magma chamber

Which of the following was a stage in the formation of Yellowstone caldera? -Crust bows upward above a magma chamber. -Material exploded from the center of the caldera. -The magma chamber emptied completely during the eruption. -Pyroclastic material erupted from a single vent.

Crust bows upward above a magma chamber.

Divergent boundaries

East african rift. Interplate volcanism. Killauea, HI. Deccan plateau.

What type of magma erupts out of dome complexes

Felsic magma

Dike cutting across sedimentary rock, grain sized, youd find in plutons

Fine-grained

shield

Fumarole Butte in Juab County, Utah is a baslatic andesitic _________ volcano.

27.7 million years

Hot spots are stationary features and can be used to measure both direction and rate of tectonic plate motion. How many years ago was Midway Island over the Hawaiian hot spot?

Development of pahoenoe

In basaltic

subduction

Island arcs are commonly associated with __________ zones.

Which type volcanic hazard consists of saturated volcanic material moving rapidly down a slope? -Volcanic ash -Lahar -Pyroclastic flow -Lava flow

Lahar

Which of the following volcanic materials flows out of a volcanic vent?

Lava

Evidence of past volcanic eruptions are present at yellowstone park

Lava flow. A caladera rim. Pyroclastic material.

topographic bulge in north flank, crater formation, earthquake swarms

List the precursor evidence (hint: 3 pieces of evidence) documented for the Mt. St. Helens eruption.

Convergent plate boundary, divergent plate boundary, intraplate

List the three volcanic zones.

What kind of viscosity would flood basalts have?

Low viscosity

Which of the following scenarios best describes how the Hawaiian Islands formed in the Pacific Ocean?

Magma generated from a hot spot burned through the overlying plate to create volcanoes.

At which of the following tectoni settings would you expect to find volcanoes producing significant amounts of very fluid, high temperature lava

Mantle plumes

Volcanic ash is best described as which of the following?

Microscopic pieces of rock ejected by a volcano

Whcih of the following best represents the relationship between earthquakes and tectonic plates

More earthquakes are found along tectonic plate boundaries that within a single tectonic plate

How often do most cinder cones erupt?

Most erupt once

Ring of Fire

Most of the world's explosive volcanoes are associated with the Pacific Ocean basin, commonly called the "__________ of __________".

Which of the following volcanoes is associated with the ring of fire

Mt. Pinatubo

Pinatubo

Mt. __________ is a stratovolcano that is the site of the second largest eruption in the 20th Century.

Cinder cones are made of?

Pyroclastic deposits

Composite volcanoes are made of

Pyroclastic deposits. Basalt flows.

Which of the following bodies of water is associated with seafloor spreading

Red sea

Greatest percentage of gases found

Rhyolitic

Greatest production of pyroclastic materials

Rhyoltic

Which of the following describes the process of the formation of the Cascade mountain range

Rising of magma to the surface. Eruption of material at the surface. Partial melting due to the presence of water.

What is scoria, and how does it differ from pumice?

Scoria is a vesicular ejecta that is produced from mafic magma. Although pumice is also vesicular, it differs from scoria in that pumice is felsic.

How to classify volcanoes?

Shape and type of deposits

What type of volcanoes are the tallest

Shiled volcanoes

Physical features associated with greatest earthquake hazard

Sierra Nevada

Tubular igneous pluton that occurs in an orientation that is cordanesnt with the bedding surface of adjacent sedimentary rocks

Sill

In which of the following regions does the greatest number of people live in areas exposed to the risk of earthquakes

Southeastern Asia

At which of the following tectonic settings would you expect to find volcanoes producing the highest columes of pyroclastic materials

Subduction of oceanic plate under continental plate

magma chamber

The Bingham Canyon Mine is an old __________ _________ with a concentration of ores that formed millions of years ago.

continental volcanic

The Cascade Range forms a __________ _________ arc that is associated with convergent plate volcanism.

True

(True/False) Most volcanoes are located within or near ocean basins at subduction zones and are composite cones.

False

(True/False) Mt. Pinatubo had only one eruption associated with volcanic activity between June and September 1991.

Which of the following would decrease the viscosity of magma? -An increase in the slope of the volcanic flank -A decrease in silica content -A decrease in temperature -An increase in dissolved gases

-A decrease in silica content

Which of Hawaii's five volcanoes are still considered to be active? -Kohala -Mauna Kea -Kilauea -Mauna Loa -Hualala

-Kilauea -Mauna Loa

Which of the following pieces of evidence for a past volcanic eruption are present at Yellowstone National Park? -Lava flows -Human documentation -Pyroclastic material -A cone shaped volcano -A caldera rim

-Lava flows -Pyroclastic material -A caldera rim

Which of the following features at Yellowstone National Park is evidence for a magma chamber beneath the park? -Welded tuff -Actively flowing lava -Rising (or bowing upward) ground near Yellowstone River -Geysers and hot springs (steam) -A thin, recent layer of volcanic ash

-Welded tuff -Rising (or bowing upward) ground near Yellowstone River -Geysers and hot springs (steam)

The following pyroclastic materials are in order from smallest to largest.

-ash -lapilli -volcanic bombs

What three factors do volcanologists monitor in order to determine whether magma is migrating toward the Earth's surface?

-changes in the patterns of earthquakes caused by the movement of magma -inflation of the volcano -the gases released from the volcano

Which materials in Hawaii's lava help to keep it fluid for longer at the surface (as opposed to cooling and solidifying quickly), thus allowing extensive lava flows to develop? -silica -iron -sulfur -water -magnesium

-iron -magnesium

The range of shield volcanoes height

300-10000 meters

Range of dome complex height

500-2000 meters

Divergent

The greatest volume of volcanic rock is produced along the oceanic ridge system, which is associated with _________ plate boundaries.

Why are shiled volcanoes wider than composite volcanoes

The lava that flows out of the shiled volcanoes is more fluid than the lava that flows out of composite volcanoes

continental crust

The magma source for Mt. St. Helens is oceanic crust, ocean sediments, and __________ __________.

mantle plumes

The main mechanism for volcanic activity within tectonic plates are __________ _________. A large head of hot magma initially rises from near the core/mantle boundary where decompression melting produces large quantities of fluid magma that progress to the surface through conduits and produce very large basaltic eruptions. Narrow, cylindrical jets of hot material continue to supply magma for continued eruptions at active volcanoes. Shield volcanoes and flood basalt deposits are the result of eruptions.

Nonexplosive eruption

Volcano fed by mafic (basaltic) magma. Volcan fed by magma with low amounts of dissolved gasses. Volcanos fed by high temperatures (1000c) magma.

Explosive Eruption

Volcano fed by silica-rich maga. Volcano fed by water rich magma.

Which of the following gases is most abundant in basaltic lava

Water vapor

Yellowstone park magma chamber beneath the park

Welded tuff. Rising ground near Yellowstone river. Geysers and hot springs (streams).

North

What general direction (i.e., north, northwest, south, southeast, etc.) was the Pacific Plate moving 55 million years ago.

25mm/year

What is the rate of movement of the North American Plate over the last 16 million years (based on the progressively older calderas associated with the hot spot)?

David Johnston

What was the name of the U.S. Geological Survey scientist killed on the north flank of Mt. St. Helens?

600,000 years

When was the last major eruption of the hot spot in Wyoming?

Yellowstone

__________ is a supervolcano found in Wyoming that is still active today.

Intraplate

__________ volcanism occurs within a tectonic plate. Form volcanic regions in the plate called hot spots.

How does the composition of a typical lava dome differ from that of a typical fissure eruption?

a lava dome's flow is silica-rich and has a high viscosity, whereas a fissure eruption is basaltic and has a low viscosity.

Which of the following would decrease the viscosity of magma?

an increase in temperature

large volumes of ash precipitating from eruption cloud.

ash falls

When contrasting lava from composite volcanoes to lava from shield volcanoes,

composite volcanoes most often produce silica-rich lavas with high viscosities, whereas shield volcanoes produce basaltic lavas with low viscosities.

Which type of plate boundary generates the greatest quantity of magma?

divergent

The volcanoes in the Ring of Fire are generally described as

having violent eruptions, as most of these volcanoes are composite cones which eject andesitic lava.

fluid mudflow of volcanic debris.

lahar

hot, fast-moving body of expanding gas and ash that hugs the flanks of the volcano.

pyroclastic flow

Which of the following has the single most immediate effect on lava's ability to solidify?

temperature

A hypothetical diagram shows a chain of four islands that extend from west to east. The westernmost island is 15 million years old, the island to the east of this island is 12 million years old, the next island to the east is 8 million years old, and the most eastern island in the chain is 4 million years old. The volcanic islands in the above figure were created as the tectonic plate passed over a hot spot in the mantle. Based on the ages of the volcanic islands, in what direction was the tectonic plate moving toward?

toward the west

destructive sea wave triggered by powerful explosions or landslides into large bodies of water.

tsunami

substances like CO2, SO2, Cl, and F that can result in climate change and be hazardous to human health.

volcanic gases