Download Sedimentary Rocks

Sedimentary Rocks
Sedimentary rocks form when
particles of other rocks or remains
of plants and animals are pressed
and cemented together.
Sedimentary rocks
Form on surface of the
earth
Often layered (bedded)
May contain fossils or
evidence of living
organisms
Kinds of sediments
Detrital/Clastic –
fragments of rocks such
as gravel, sand and clay
– Sandstone
– Coquina
 Organic – sediments formed
from the remains of plants
and animals
– Coal
Chemical – mineral
grains that precipitate
out of solution by
evaporation or chemical
action
– Ex: Limestone
Weathering
 Existing rocks are broken down by physical and chemical
weathering
 Weathering prepares rocks for erosion and transforms rocks
into the raw materials that will become sedimentary rocks
 Two types: Chemical and Physical
Erosion and Weathering
 Erosion – the picking up and physical removal of rock
particles
 Weathered and eroded material can be transported by rivers,
streams and glaciers
 What are some methods of erosion?
 Water Erosion
Wind Erosion
Sorting sediments
When a river flows into an
ocean or lake it drops sediments
as its speed is reduced.
Sediments to sedimentary rock
– Deposition
– Compaction
– Cementation