Transcript Document

Sedimentary Rocks
Sands, gravel, and conglomerates
-Oh my!
Where can I find a sedimentary
rock?
 Cover approximately 75% of our (continental) surface
 Examples:
 Sandstone
 Conglomerate
 Shale
 Halite
Formation
 Weathering
 Erosion/Transportation
 Deposition
 Compaction
 Lithification
Weathering
Weathering- the breakdown of rocks; disintegration of rock
 Chemical
CO2 + H2O  H2CO3
carbon dioxide + water carbonic acid
H2CO3 + CaCO3  Ca(HCO3)2
carbonic acid + calcium carbonate  calcium bicarbonate
 Mechanical
Temperature (freeze/thaw, thermal expansion)
Pressure release
Other (crystal growth, organic activity,etc.)
Erosion & Transportation
Erosion- the movement of rocks or weathered products
Agents of Erosion
Wind
Water
Ice
Gravity
 Size and shape of clasts relate to transportation
 Large and angular
Small and rounded
Deposition
Sediments are deposited or dropped when their
transportation no longer has the energy to move the mass.
Compaction
Pore spaces are reduced when sediments are compacted,
or pressed together
Lithification
During lithification
loose sediments are
cemented together
to form a
sedimentary rock.
The Exceptions
When it’s not a Clastic Sedimentary Rock
Organic Sedimentary Rocks:
Chalk
Limestone
Coal
Precipitate Sedimentary Rocks:
Halite (salt)
Gypsum
Name the sedimentary rock!