Page 175 - Laboratory Manual in Physical Geology

ACTIVITY ACTIVITY

6.1 Sedimentary Rock Inquiry 6.2 Mount Rainier Sediment
Analysis
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THINK What do sedimentary rocks look like?
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About It How can they be classified into groups?
THINK What are sedimentary rocks made of,
About It and how are they formed?

OBJECTIVE Analyze and describe samples of
sedimentary rocks, then infer how they can be

OBJECTIVE Investigate sediment forming on and
classified into groups.

near Mount Rainier, WA.
PROCEDURES
PROCEDURES
1. Before you begin , do not look up defi nitions and
1. Before you begin , read about Sedimentary
information. Use your current knowledge, and
Processes, Composition, and Textures of
complete the worksheet with your current level of
Sediments and Sedimentary Rocks below. Also,
ability. Also, this is what you will need to do the
this is what you will need :
activity:
___ Activity 6.2 Worksheet (p. 172 ) and pencil
____ Activity 6.1 Worksheet (p. 171 ) and pencil
___ optional: computer with access to Google
____ optional: a set of sedimentary rock samples
Earth™
(obtained as directed by your instructor)
2. Then follow your instructor’s directions for
2. Analyze the rocks, and complete the worksheet
completing the worksheets.
in a way that makes sense to you.
3. After you complete the worksheet , read the
Introduction below, and be prepared to discuss
your observations, interpretations, and inferences
with others.
ACTIVITY
6.3 Clastic and Detrital
Sediment
Introduction
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Sedimentary rocks form when sediments are THINK What are sedimentary rocks made of,
compressed, cemented, or otherwise hardened together. About It and how are they formed?
Some sedimentary rocks form by a process similar to
mud hardening in the Sun to form adobe . Others form OBJECTIVE Analyze clastic and detrital sediment
when masses of intergrown mineral crystals precipitate and infer the environment in which sedimentary
from aqueous (water-based) solutions and lock together grains formed.
to form crystalline rock, like rock salt that remains PROCEDURES
when ocean water is evaporated.
Sediments are loose grains and chemical residues 1. Before you begin, read about Sedimentary
of Earth materials, including rock fragments, mineral Processes and Composition and Textures of
grains, parts of plants or animals like seashells and Sediments and Sedimentary Rocks below. Also,
twigs, and chemical residues like rust (hydrated iron this is what you will need:
oxide residue). Grains of sediment are affected by ___ Activity 6.3 Worksheet (p. 174 ) and pencil
chemical and physical weathering processes until they ___ hand lens or stereo zoom microscope
are buried in a sedimentary deposit or else disintegrate ___ grain size scale cut from GeoTools Sheet 1 or 2
to invisible atoms and molecules dissolved in water ___ small piece of shale
(aqueous solutions), like groundwater (water beneath ___ medium quartz sandpaper
Earth’s surface), lakes, streams, and the ocean. The ___ 2 small pieces of granite or diorite
salty taste of ocean water or salty lake water (e.g., Great ___ optional: computer with access to Google
Salt Lake or the Dead Sea) is a clue that many Earth Earth™
materials are dissolved into it, but even fresh water has 2. Then follow your instructor’s directions for
some materials dissolved in it (just not as many). Only completing the worksheets.
distilled water has no materials dissolved in it.

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