formation of sedimentary rock powerpoint
DESCRIPTION
sedimentary rocksTRANSCRIPT
SEDIMENTARY ROCKSThere are 2 ways sedimentary rocks are formed
1. Clastic are made from sediments glued together
2. Non-clastic: not glued together---include chemical & biochemical/organic
SEDIMENTARY ROCKS WILL CONTAIN FOSSILS.
SEDIMENTARY ROCKS FORM IN LAYERS CALLED STRATA
Oldest rocks are on the bottom….youngest on top
This is a good example of Stratification
1. CLASTIC Sedimentary Rocks are made from sediments that come from pre-existing rocks that have been weathered (breaking down into smaller pieces) and eroded (transported away) then glued together.
THE 2 CLASSES OF SEDIMENTARY ROCKS
The 2 types of weathering include physical (only size changes) and chemical (a new substance is formed).
Sediments range in size from tiny pieces of clay to sand, to pebbles, and to stuff as big as boulders
Clastic rocks form in a process called lithificaton which means compaction and cementation are occurring
Here’s How They Form:•Layers of sediment are deposited at the bottom of oceans and lakes
•As the layers build one on top of another, the pressure on the bottom layers COMPACTS the sediments together
•In the empty spaces between sediments, natural glues, like calcite, CEMENT the sediments together
Demo of
Sedimentator
Look at the processes that are occurring in
this animation
Clastic Process
Examples of clastic sedimentary rocks include
CONGLOMERATEBRECCIA
SANDSTONESHALE
2. Non-Clastic contain 2 types: chemical and biochemical
CHEMICAL Sedimentary Rocks are made from mineral crystals that formed from chemicals dissolved in water.
Here’s How They Form:•The water in the oceans, lakes, and underground is often full of dissolved minerals like halite and calcite.
•Water evaporates leaving the solids behind: rock salt is formed when salt is left after evaporation and limestone is formed when calcite is left behind
Limestone Cave
Chemical Sedimentary Rocks are also formed in caves where mineral-rich water drips from the ceiling, creating stalactites and stalagmites made out of limestone
Limestone
Examples of chemical sedimentary rocks include limestone and rock salt
BIOCHEMICAL OR ORGANIC Sedimentary Rocks are made from remains of once-living plants or animals (organic matter)
COQUINAMade from
shells
CHALKMade from dead
animals
Biochemical sedimentary rocks include: coquina, chalk, coal and limestone
•this is the sedimentary rock type with the most fossils
•will be found near areas of lots of biological activity
COAL
Made from dead plants
LIMESTONE with
fossils in it
AMAZING EARTH SCIENCE FACTS
1. Sedimentary rocks form 3 ways:1. _________ --compacted & cemented2. Chemical3. _______________
2. Sedimentary rocks are found in flat _________ or strata.
3. _______ are found in Sedimentary Rocks.
4. ____________is formed both chemically and organically.
Clastic-
layers
Fossils
Limestone
Biochemical
5. Clastic rocks are made of _____________, examples are conglomerates, sandstone and shale
6. Chemically formed sedimentary rocks form from _____________ ocean water, which leaves behind evaporates like ___________.
sediments
evaporatingrock salt