Sedimentary Rock Identification Lab

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Sedimentary Rock Identification Lab
Sandstone Arches
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How is a sedimentary Rock formed???
Why is the earths surface 75 sedimentary
rocks?????????
Erosion
Sediment
Pre-existing Rock
Water, Wind, Ice
Breaks down Pre-existing rock
Rivers
Deposited
Transported
Lakes
Compacted Cemented
Lithified
Sedimentary Rock
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Three major categories of Sedimentary
Rocks Clastic Sedimentary rocks Chemical
Sedimentary rocks Bio-chemical (bio-clastic)
Sedimentary rocks
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Clastic (inorganic-detrital) rocks are composed
of particles or grains. Rock name is dependent
on grain size.
Decreasing grain size
2 mm
2 mm
1/16 mm
1/256 mm
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Chemical Rocks Inorganic, non-clastic rocks
that are commonly the result of
evaporation and precipitation Chemical rocks
contain no fossils, or biological material but
may react with HCl
The Great Salt Lake, Utah halite (salt) crystals
Carbonate- chemical rocks stalagmites
Chemically precipitated SiO2
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Bio-chemical (bio-clastic) rocks Result from
animal and plant secretions. The term
clastic indicates that these rocks contain
fossils or parts of plants shells, compacted
plat material
Animal parts
Cemented shell fragments
Lithified plant material
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Classification Procedure
Step 1 Determine if the rock is clastic or
non-clastic
Step 2 If the rock is clastic, determine the
grain size and diagnostic
properties. Make the ID.
Step 3 If the rock is not clastic, determine
if the rock is either chemical or
bioclastic chemical will not contain particles
such as grains and
organic material. Test rock to observe
fizzing (carbonates) Match
diagnostic properties
on chart for ID bio-clastic- rock will be
composed of particles that are
organic- animal parts, plant secretions.
Test rock to observe fizzing
(carbonate) Match diagnostic properties
on chart for ID