Transcript Land-derived Clastic Sedimentary rocks form by

Aim: How do sedimentary rocks form?
Do Now: Using your ESRT page 6,
list the type(s) of rocks that can
become sedimentary rocks.
Describe what is found in the rock?
How did it get there?
How do sedimentary rocks form?
Land-Derived
(Clastic) Sedimentary
Rocks
How are land-derived sedimentary rocks formed?
Land-derived Clastic
Sedimentary rocks form by:
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Weathering- rocks break down into
smaller pieces called sediment.
Erosion- Sediments are transported
by wind, water, ice, or gravity.
Deposition: sediments are dropped
and buried
Compaction: overlying sediment
apply pressure and squeeze
sediments together
Cementation – natural “glue” of
dissolved minerals in water that
binds grains of sediment together
Lithification
How else can sedimentary rocks form?
How are sedimentary rocks formed
chemically or organically?
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Chemical / Crystalline –
minerals come out of
solution by precipitation or
evaporation, leaving
crystals behind.
Ex. When saltwater evaporates
 rock salt
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Organically / Bioclasticformed from organic
matter such as plant or
shell remains.
Ex. Coquina or limestone
How are the sedimentary rocks classified on page 7 of the ESRT?
Precipitation &
Evaporation
Compaction &
Cementation
(Lithification)
Formation
Process
Lithification
shell / plant
fragments
MARINE/
According to the texture, Identify the two major
groups of sedimentary rocks?
Clastic and
Nonclastic rocks
How do we differentiate between clastic and nonclastic rocks?
1. Clastic rocks – fragments of
rocks compacted & cemented
together
*** Clastic rocks are classified
by their grain size ***
2. Non-clastic rocks – made from
dissolved minerals or plant /
shell remains (no sediments)
Determine the characteristics that can be seen in
these sedimentary rocks?
Layers
Rock Fragments
FOSSILS
Mud cracks
Rain-drop impressions
**ONLY Sedimentary Rocks
contain Fossils**
Summary Activity ESRT page 7
1. Why are sedimentary rocks the only rock
types that contain fossils?
2. How can sedimentary rocks form?
Extra Summary Questions