NAME
DATE
CLASS
Chapter 6
Use with Section 2
REINFORCEMENT
Igneous Rocks
Complete the crossword puzzle using the clues below.
1
3
2
4
5
6
7
8
9
10
Across
1. Lava that cooled quickly and entrapped
air and other gases, similar to scoria
Down
2. Rock formed when magma cools slowly
beneath Earth’s surface
4. One of two conditions needed to melt
minerals into magma
3. Molten material below Earth’s surface
7. Light-colored igneous rocks
5. Igneous rock formed when lava cools at
or near Earth’s surface
8. Dark-colored igneous rocks rich in iron
and magnesium
6. Another name for the mineral crystals in
cooling magma or lava
9. An extrusive igneous rock that is
actually glass
10. Molten materials that flow from
volcanoes
26
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
Chapter 6 Rocks Review
Name
Date
Period
Use the words in the box to fill in the blanks.
FINE
DENSE
FORMATION
RADIOACTIVE
MINERALS
IRON
MAGMA
SURFACE
CRYSTALS
MAGNIFICATION
SLOW
COARSE
IGNEOUS
PRESSURE
PORPHYRY
LAVA
SILICON
FELSIC
INTRUSIVE
VESICLES
Rocks formed from molten Earth materials are
LIGHTER
ABUNDANT
MAFIC
EXTRUSIVE
SCORIA
rocks. There are two kinds
of molten materials: magma and
. Heat and
caused by overlying rocks and soil and
elements produce magma. When magma cools below Earth’s surface, it forms
igneous rocks. The
-grained,
of these rocks grow large
rate of cooling. When magma moves to Earth’s
because of their
, it is called lava. When lava cools on Earth’s surface it forms
- grained,
igneous rocks. Mineral crystals of
extrusive rocks are so small,
is needed for identification. Igneous
rocks that are fine grained with a few larger crystals in them are called
igneous rocks like pumice and
. Some
have escaping gases in them called
. Igneous rocks can be classified by their
also can be identified by the type of
. They
in them.
igneous rocks are dark colored, heavy and
magnesium.
. They contain
igneous rocks are
less dense. They contain a lot of oxygen and
on Earth.
and
in color and
Igneous rocks are the most