Download Sedimentary rock - Grand Canyon School

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Sedimentary Rock usually layered, that results from the consolidation or
lithification of sediment, for example a clastic rock like sandstone or a
chemical rock like rock salt, or an organic rock like coal.
• Sedimentary Rock are either Marine (deposited in the ocean) or nonmarine
(deposited on the continents). If marine sedimentary rock are present, the area
must have been below sea level.
Sedimentary Rock
• Clastic – fragments of rocks and minerals that have been physically
transported and deposited and then converted into rock
• Chemical – Direct precipitation of minerals from a solution. Only
chemical sedimentary rocks are affected by chemicals (vinegar/acid),
all others are not affected by moderate acids.
• Biochemical/Organic- Remains of plants and animals that have been
converted into rock
Clastic Sedimentary Rock
• made up of mostly of fragments derived from preexisting rocks and transported mechanically to
their places of deposition.
• made up mostly of fragments, called clasts (means
broken) that are eroded from other rocks.
• Everything discussed in S-2-W
Clastic Sedimentary Rock
These rocks are further classified by the sizes of their
particles
• Coarse-grained; Gravel (pebbles to boulders, bigger than
2mm) Photo ?
• Medium-grained; Sand (1/16 to 2 mm) Photo ?
• Fine-grained; Clay or Mud (Smallest 1/16 mm or smaller
Photo ?
Photo A
Photo B
Photo C
Chemical Sedimentary
• Rocks consist of materials that
have precipitated from the
ocean water or lake
• Precipitation: the process of
forming solid mineral
constituents from a solution by
evaporation
Organic Sedimentary Rock
• a sedimentary rock consisting
mainly of the remains of
organisms
• Consists of the mineral calcite,
a calcium carbonate mineral
with the formula CaCO3
• Organic Sedimentary Rock
forms when plants in swamps
with rich vegetation die and are
buried by the remains of later
plants
Compaction and Cementation
Compaction and Cementation
Compaction: The reduction in bulk volume or thickness of fine-grained
sediments owing to increasing weight of overlaying material that is
continually being deposited
Cementation: The process by which sediments are converted into rock
by the precipitation of a mineral “cement” among the grains of
sediment
Lithification is the process of sediment that gradually becomes
converted to solid rock
Classification
• Classification, or the grouping or ordering of
objects by similar features, is meant to make it
easier for people to think about and discuss what
they are investigating
• Distinguishing features of the rock samples will
include things like the size of grains, the shape of
the grains, what the grains are made of, if there are
any visible fossils, and how the rock feels and
even tastes.
Vocabulary
• Key Vocabulary: Sedimentary Rock,
Compaction, Cementation, Bedrock,
Clastic Sedimentary Rock, Clast,
Precipitation Chemical Sedimentary
Rock, And Organic Sedimentary Rock