Name: ____________________________________ Date: __________________ Period: ______
Chapter 10.2: Igneous Rocks
1. Igneous Rocks
a. Igneous ______________ form when ________________ cools and
___________________.
b. _______________ rocks are ___________________ into two groups:
________________________ & __________________________
i. __________________ igneous rocks form when ____________
from __________ below the earth’s ________ cool and harden.
1. We _______ them intrusive because the _____________
that forms them ________________, or enters, into other
rock ______________ beneath the earth’s ____________
and slowly cools.
ii. _________________ igneous rocks are ________________ the
rapid cooling of __________, or melted rock on the earth’s
__________________.
c. Intrusive and extrusive _______________ rocks differ mainly in the
___________ of their crystalline ________________ masses or grains
which is called _________________.
d. The texture of igneous ____________ is determined by the
______________ rate of the ____________ or _________ that formed
the rock.
2. Texture of Igneous Rocks
a. Since _______________ igneous rocks are formed by ____________
cooling and ________________ of magma ________________, there
is plenty of ____________ to form large, well developed
_________________________ grains.
i. These _____________ are formed of large mineral __________
and have a _____________ grained texture.
ii. An example is _________________.
b. When ____________________ igneous rocks _________ and harden
________________ on the surface of the ________ there is not much
time for ____________ crystalline grains to _________, and therefore
produce ____________ grained rock.
i. An example of this type of rock is _________________.
c. Sometimes ________________ rocks form from magma that cools
____________ at first and then _____________ as it nears the earth’s
__________________.
Name: ____________________________________ Date: __________________ Period: ______
i. This type of _______________ produces large _____________
embedded within a ____________ of smaller crystals.
ii. ______________________ texture is described by __________
and _______________ crystals.
d. When highly ______________, silica rich __________ cools rapidly,
the resulting rock has no _______________.
i. An example of this type of rock is ______________ or volcanic
___________.
e. When _______________ that contains a ____________ proportion of
dissolved _____________ cools rapidly, the gases may become
________________ in the rock and produce a rock full of _________.
i. An example of this type of rock is ________________.
3. Composition of Igneous Rocks
a. The mineral ___________________ of an igneous rock is determined
by the __________________ composition of the ____________ from
which the rock ____________________.
b. ________________ rocks have been divided into _________ families
based on mineral composition: ______________, _______________,
and ____________.
i. Felsic ___________ form from ____________ that are high in
______________.
1. Examples of rocks in the ___________ family include
____________, ______________, and ______________.
ii. ____________ rocks form from _____________ that are low in
_________ but rich in iron and __________________.
1. Examples of rocks in the mafic family include
_________________ and _________________.
iii. ___________________ igneous rocks contain less __________
than rocks in the ____________ family and have a color that
falls ________________ felsic and mafic _________________.
1. Examples of rocks in the intermediate family include
________________ and _____________________.
4. Igneous Rock Structures
a. Igneous rock __________________ that form ___________________
are called ____________________.
i. _____________________ are the _________________ of all
intrusions and have at least _______ square kilometers of
surface ___________________.
Name: ____________________________________ Date: __________________ Period: ______
1. The word batholith means “___________ __________.”
2. Batholiths form the _________ of many major mountain
_________________.
ii. A ___________ is an intrusion similar to a ________________
but covers _______ than 100 square kilometers.
iii. A _________________ forms when magma ________ between
rock _______________ and spreads upward _______________
the overlying rock into an _______.
1. Laccoliths can sometimes be identified by _________
dome shaped ______________.
iv. A ________ is formed when a ___________ of magma flows
between the ______________ of rock and _______________.
1. A sill will lie ______________ to the rock ___________
surrounding it, even if the layers are ________________.
v. A ____________ is formed when ____________ forces its way
through ___________ layers by following _________________
vertical ________________ or by creating new ones and
___________________.
b. Igneous rock _______________ that form on the _____________ are
called ___________________.
i. A volcanic _________ forms when a ______________ volcano
weathers down to only the _________, solidified rock in the
__________.
ii. A lava _________________ forms from lava that ________ out
of long ______________ in the earth’s surface, ____________
out over a _______ area, and fills in __________ covering hills.
1. Once the _________ is ________________ it forms a
_______________________.