Download Extrusive rocks form when lava cools at the surface.

Name:_________________________________________
Date:_______________
Pre-Test: Outcome 3 – Rocks and Minerals
1. What is the difference between extrusive and intrusive igneous rocks?
- Extrusive rocks form when lava cools at the surface. The lava cools quickly so you do not see
large crystals in the rocks. Extrusive rocks often have glassy textures and can form gas pockets.
Intrusive rocks form when magma cools underneath the surface. The magma cools slowly so it
allows large crystals to grow. If large crystals grow, we describe the texture as course.
2. What are the properties of identifying minerals? (Name at least 3)
-Streak
-Fracture/Cleavage
-Hardness
3. How do mineral crystals grow?
-Mineral crystals grow when magma cools at a slow rate. We commonly see large crystals in
intrusive igneous rocks that were cooling underneath the surface.
4. What type of rocks are formed from by intense heat and pressure deep inside Earth's crust?
(1) igneous rocks
(2) metamorphic rocks
(3) sedimentary rocks
5. Obsidian’s glassy texture indicates that it formed
(1) slowly, deep below Earth’s surface
(2) slowly, on Earth’s surface
(3) quickly, deep below Earth’s surface
(4) quickly, on Earth’s surface
6. The most abundant metallic element by mass in Earth’s crust makes up 8.23% of the crust.
Which group of minerals all normally contain this metallic element in their compositions?
(1) garnet, calcite, pyrite, and galena
(2) biotite mica, muscovite mica, fluorite, and halite
(3) talc, quartz, graphite, and olivine
(4) plagioclase feldspar, amphibole, pyroxene, and potassium feldspar
7. Which processes lead directly to the formation of igneous rock?
(1) weathering and erosion
(2) compaction and cementation
(3) heat and pressure
(4) melting and solidification
Base your answer to the question on the data table below and on your knowledge of Earth
science. The table provides information about four minerals, A through D.
The diagram on the right represents a sample of mineral A.
8. Mineral A is most likely
(1) garnet
(2) galena
(3) olivine
(4) halite
Base your answer to the question on the table and photograph below and on your
knowledge of Earth science. The table shows the approximate mineral percent
composition of an igneous rock. The photograph shows the true-scale crystal sizes in this
igneous rock.
9. Identify two elements that are commonly found in all three minerals in the data table.
-Silicon (Si), Aluminum (Al) and Oxygen (O)
Base your answer to the question on the diagram below, which represents a rock composed of
cemented pebbles and sand.
10. This rock should be classified as
(1) an intrusive igneous rock
(2) an extrusive igneous rock
(3) a bioclastic sedimentary rock
(4) a clastic sedimentary rock
11. Which change would most likely occur if this rock became buried deep within Earth’s crust
and was subjected to intense heat and pressure, but did not melt?
(1) The density of the pebbles and sand would decrease.
(2) The rock would become a plutonic rock composed mostly of quartz.
(3) The rock would become more felsic with a higher concentration of magnesium.
(4) The pebbles would become distorted and the sand would be recrystallized
12. Base your answer to the question on the geologic cross section below, which shows rock
units 1 through 7 that have not been overturned. Some of the rock units contain New York State
index fossils. An unconformity exists between rock units 5 and 6.
Identify one metamorphic rock that could have been formed by the contact metamorphism within
rock unit 1.
-Marble or hornfels
13. The geologic cross section below shows several rock units of Earth’s crust. Some rock units
are labeled A through E.
Which two rock units formed from sediments deposited in horizontal layers?
(1) A and B
(2) B and C
(3) C and D
(4) D and E
14. A nonvesicular rock is made entirely of green 2-millimeter-diameter crystals that have a
hardness of 6.5 and show fracture, but not cleavage. The rock is most likely
(1) shale
(2) phyllite
(3) dunite
(4) schist
15. Which texture best describes an igneous rock that formed deep underground?
(1) glassy
(2) vesicular
(3) fine grained
(4) coarse grained
16. Mineral crystals of quartz, biotite mica, and amphibole are produced primarily by the
(1) chemical reaction of elements in seawater
(2) cooling and solidification of magma
(3) deposition of sediments by a glacier
(4) metamorphism of bituminous coal
17. Which mineral will scratch fluorite, galena, and pyroxene?
(1) graphite
(2) calcite
(3) olivine
(4) dolomite
18. Which element, found in both biotite mica and muscovite mica, makes up the greatest
percent by volume of Earth’s crust?
(1) nitrogen
(3) potassium
(2) oxygen
(4) silicon
19. The bedrock of the Adirondack Mountains was formed mainly by the
(1) cementation of clastic sediments and precipitates from seawater
(2) compaction and recrystallization of volcanic material
(3) regional metamorphism of sedimentary and igneous rocks
(4) contact metamorphism of unconsolidated gravels
20. What is the color and type of rock that forms oceanic crust at mid-ocean ridges?
(1) light colored and igneous
(2) light colored and sedimentary
(3) dark colored and igneous
(4) dark colored and sedimentary
21. Base your answer to the question on the diagram below, which shows several different
landscape features. Points X and Y indicate locations on the stream bank.
The beach consists of particles with diameters from 0.01 cm to 0.1 cm. Identify the sedimentary
rock that will form when burial and cementation of these sediments occur.
-Sandstone