geology final study guide

The most common volcanic rock that found in lava flows would be on composite volcanoes is

Andesite

The downfall of which ancient civilization in the Mediterranean closely followed the caldera-forming eruption at Santorini?

Minoan

Which of the following factors indicate high risk for volcanic mudflows or lahars?

a volcano with a thick covering of snow or ice

Composite volcanoes are so called because they:

are composed of lava flows, pyroclastic material and mudflows

Which of the following is the correct relationship between stream velocity and sediment load?

as velocity increases so does the streams capacity to carry a larger load

Which of the following is not a volcanic hazard made worse by being located along a river valley directly downhill from a volcano?

burial by falling ash

Eruptions on the islands of Santorini in Greece and Krakatau in Indonesia resulted in:

collapse of a huge caldera, huge ash column and pyroclastic flows, destructive waves

The relatively large symmetrical volcano contains interlayered lava flow pyroclastic deposists and volcanic mudflows. What kind of volcano is it?

composite volcano

Prior to an eruption, the surface of a volcano may rise centimeters to hundreds of meters as a result of:

injecting magma inflating mountain

Volcanic mudflows (lahars) are common on composite volcanoes because:

large amounts of ash and snowmelt mix with loose ash on steep slopes

The downfall of which ancient civilization in the Mediterranean closely followed the caldera-forming eruption at Santorini?

minoan

Which tectonic setting is interpreted to be the cause of volcanism at Yellowstone?

movement of North America over a mantle plume

The volume of water flowing through any part of a river per unit time is calculated by:

multiplying the velocity by cross sectional area of the river

A volcano has a Plinian eruption with an eruption column 9 km high. What is the overall climatic effect of that ash cloud?

regional warming

Which of the following is NOT a hazard associated with ash cloud and ash fall?

structures catching on fire

Some scientist think that yellowstone could cause a future disaster because:

the area is part of a caldera, scientists think that magma is still present, past eruptions have carried ash over, land is yellowstone is uplifting in places and subsiding in others.

What does it mean when the amount of SO2 emitted from the vent of a composite cone or caldera quickly decrease?

the volcano has stopped degassing because of an obstruction at the vent (gas trapped in the magma)

Which of the following are ways that viscosity affects gasses in magma?

viscous magma prevents gas from escaping easily

All of the following are lines of evidence written by Plato that support the hypothesis that Santorini is the location of the lost city of Atlantis except:

zeus the god of sky and thunder sent "lightening and thunder" onto the city