Download Geology: Inside the Earth Chapter 1 Notes and Vocabulary

GEOLOGY: INSIDE
THE
EARTH CHAPTER 3 VOLCANOES
Chapter 3: Volcanoes
See pp. 80-111
Big Idea: Forces Inside Earth
Essential Question: What causes volcanoes and how do they affect Earth’s surface?
As tectonic plates move due to _____________ ___________ in Earth’s _________, __________ builds up
along the lithosphere’s ________________ and weak areas in Earth’s crust called ________ _____.
__________________ rises through the __________ in these stressed places to form a _______________.
Most volcanoes form due to the forces built up from ________________ (at ____________ boundaries) and
_______________ (at ____________ boundaries). The Earth’s surface is affected when _____________ to
form new landforms like ____________________, _________________, and _______________.
_______________ from erupting volcanoes covers the surface and eventually becomes part of the
__________________.
Section 1: Volcanoes and Plate Tectonics
____________: A vent (opening) in the Earth's surface through which magma erupts; it is also the landform
that is constructed by the eruptive material.
___________: Molten rock containing liquids, crystals, and dissolved gases that forms within the upper part
of the Earth's mantle and crust. When erupted onto the Earth's surface, it is called lava.
____________: The term used for magma once it has erupted onto the Earth's surface
___________ ____ _________: a major belt of volcanoes that rims the Pacific Ocean
__________ __________: An area in the middle of a lithospheric plate where magma rises from the mantle
and erupts at the Earth's surface.
___________ _________: a string of islands formed by the volcanoes along a deep-ocean trench

Most volcanoes are found along the ____________ of Earth’s plates and over ________ _______.
Section 2: Properties of Magma
____________: a substance that cannot be broken down into other substances by ordinary chemical or
physical means
____________: a substance made of two or more different elements that have been chemically combined
____________ _________: any characteristic of a substance that can be observed or measured without
changing the composition of the substance
____________ __________: any property that produces a change in the composition of matter
__________: the major ingredient of magma; made of the elements oxygen and silicon; silica content ranges
from 50 to 70% and affects viscosity.
_____________: Measure of the fluidity of a substance. Lower viscosity magma flows quickly and cools to
form basalt. Higher viscosity magma flows poorly and cools to form rhyolite (like granite).
____________: relatively hotter, faster flowing lava that has a smooth, hummocky or ropey surface
____: relatively cooler, slower flowing lava that has a rough, rubbly surface composed of broken lava blocks

Each substance has a particular set of physical and chemical properties that can be used to _________ a
substance or to ___________ how it will ______________.
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
Viscosity is the ___________to flowing. Some liquids flow more easily than others (low viscosity).

The viscosity of magma depends upon the __________ ___ _________ and _______________.
__________ silica increase viscosity. __________ temperature increases viscosity.
Section 3: Volcanic Eruptions
________: the main opening in a volcano
through which magma and gas escape
_______: the bowl shaped
area around the central vent
______: molten rock flowing
over Earth’s surface
______ ______: a conduit on the side of
the volcano through which magma escapes
______ _____: the area covered
by lava as it flows out of a vent
_______: the long tube underground
that connects the magma chamber to
the surface
_________ ________: the
pocket of magma beneath
the surface
________:
molten rock underneath
Earth’s surface
__________ _______: a ground hugging avalanche of hot ash, pumice, rock fragments and hot, toxic gas that rushes
down the side of a volcano as fast as 100 km/hr. Temperatures can exceed 500° C.
__________________: A volcano that is currently erupting, or has erupted during recorded history.
_______________________: An active volcano that is in repose (quiescence) but is expected to erupt in the future.
_____________________: A volcano that is not expected to erupt again.
 The forces in ___________, expanding __________ push magma from the magma chamber through the pipe and out of
the vent during a volcanic eruption.
 Eruptions can be either ______ or __________, depending on the ______________________.
 ______ eruptions result from ____ _______, ___________ magma, and can result in ____ and ___________.
 ___________ eruptions result from _________, _____________ magma, which can plug the vent and cause a _______
___ __ ________. Explosive eruptions feature ________and pyroclastic flow, and can result in rocks like __________
and ____________.
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 Geologists monitor volcanoes for ___________, changes in ________________, __________________,
________________________ and ____________________.
Section 4: Volcanic Landforms
___________ Volcano
__________ _________ Volcano
____________ or Stratovolcano
A volcano that has long
gentle slopes produced by
repeated eruptions of runny
lava flows. Galapagos Isl.
A steep-sided volcano formed
by the explosive eruption of
cinders that form around a vent.
Cinders are lava fragments
about 1 cm. Paricutin
A steep-sided volcano built by
alternating eruptions of lava
flows and tephra (rocky debris)
deposits.
Mt. Saint Helens & Mt. Shasta
_____________:
the hole left by the collapse of
a volcanic mountain
_____________ __________:
a landform that results from magma
hardening in a volcano’s pipe
______________:
A massive rock that forms when
magma hardens inside the crust
________ _________:
a landform built from
repeated lava eruptions
http://core.ecu.edu/geology/woods/NewIgRxQuesAnsw2008_files/image004.gif
_______: hardened rock formed
when magma squeezes between
horizontal layers of rock
______: hardened rock formed
when magma forces itself
across vertical layers of rock
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__________: a fountain of
geothermally-heated water and
steam that erupts from the ground
(see also hot springs)
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