Download ROCK CYCLE and IG RX

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GEOL 1101 LAB #2 ROCK CYCLE AND IGNEOUS ROCKS
1. List the type of rock that would form under the following situations. Types of rocks may be: plutonic
igneous rocks; volcanic igneous rocks; clastic (detrital) sedimentary rocks;
chemical sedimentary rocks; biochemical sedimentary rocks; metamorphic rocks
a magma rises to a depth of 3 km below the surface and crystallizes at depth
ROCK THAT FORMS = ______________________
a metamorphic rock is exposed at the surface, weathers, and the resulting broken up rock
pieces are transported by a stream, then deposited and cemented together
ROCK THAT FORMS = ______________________
a small desert lake evaporates and forms a rock
ROCK THAT FORMS = ______________________
a magma migrates along fractures in the crust and erupts at the surface
ROCK THAT FORMS = ______________________
rocks at the boundary of two colliding plates get subjected to very high pressures and
but remain solid
temperatures
ROCK THAT FORMS = ______________________
microscopic plankton in the ocean make shells of calcite that accumulates on the ocean floor
the plankton die
when
ROCK THAT FORMS = ______________________
2. Define ROCK TEXTURE:
3. What is the difference in the way in which plutonic (intrusive) igneous rocks form and the formation of
volcanic (extrusive) igneous rocks?
4. Explain what has to occur before plutonic rocks can be exposed at the surface so that we can see them.
5. Using the Lecture Notes and your text, describe two ways rocks can melt WITHOUT increasing the
temperature.
6. For EACH of the two ways of melting described in question 5, list the geologic environment (tectonic setting)
where this melting method can occur.
QUESTION 7 is optional, and can be completed for up to 3 pts extra credit on Lab Exam 1
7. Use Bowen’s reaction series (in text, Lecture Notes, and Identification Charts) and the Igneous rock
identification chart to determine the compositions A, B, C, and D; then name the rocks that form (P = plutonic;
V = volcanic) below the chart.
8. What type of texture do plutonic (intrusive) igneous rocks have?
EXPLAIN how this plutonic rock texture forms.
9. What are the four types of textures that volcanic (extrusive) igneous rocks may show?
For EACH volcanic rock texture, EXPLAIN how the texture will form.
10. Using the Lecture Notes and your text, name the plutonic bodies shown on the picture below.
(A is > 100 km2 and E is < 100 km2)
A=
B=
C=
D=
E=
F=
11. The plutonic body labeled “F” in question 10 forms when magmas are very viscous. Describe what is
meant by a viscous magma, and explain the composition of magma that will be viscous.
12. The plutonic body “A” in question 11 is felsic in composition. Name the rock that composes plutonic body
“A”. (hint: see Igneous Rock Identification Chart and optional question 7 above)
13. If the magma forming “A” erupted, what would be the name of the rock that forms?
From the Lecture Notes and class discussions, answer questions 14 – 21.
14. What is the relationship between the Red Bluff Granite and the Thunderbird Rhyolite? How old are they?
15. What is a pegmatite? Why do they have such large crystals?
16. What is a maar crater? Name one of the maar craters near El Paso.
17. What type of plutonic body is Mt. Cristo Rey? (see picture of plutonic bodies in question 10)
18. What type of plutonic body is the Campus Andesite?
19. Name the 3 main types of volcanoes discussed in class and describe the characteristics of each type.
20. Which type of volcano is Black Mountain? Approximately how old is Black Mountain and the volcanic areas
like the Potrillo Volcanic Field? What type of volcanic rock is erupted in these areas?
21. Match the samples A – E to the correct name.
Red Bluff Granite: _______
Thunderbird Rhyolite: _____
Campus Andesite: __________
Volcanic rocks from Black Mountain and Potrillo Volcanic field: __________________
22. Use the IGNEOUS ROCK IDENTIFICATION CHART and the MINERAL IDENTIFICATION CHART to
complete the chart below:
IGNEOUS
ROCK OR
MINERAL
1
2
TEXTURE, IF
SAMPLE IS
IGNEOUS ROCK
MODE OF
ORIGIN, IF
SAMPLE IS
IGNEOUS ROCK
NAME VISIBLE MINERALS, OR
COLOR FOR IGNEOUS ROCK
SAMPLE NAME
3
4
5
6
7
8
9
IGNEOUS
ROCK OR
MINERAL
10
11
12
13
14
15
16
17
18
19
20
TEXTURE, IF
SAMPLE IS
IGNEOUS ROCK
MODE OF ORIGIN,
IF SAMPLE IS
IGNEOUS ROCK
NAME VISIBLE MINERALS, OR
COLOR FOR IGNEOUS ROCK
SAMPLE NAME