Transcript Sedimentary Rock - Treynor Schools

Sedimentary Rock
How is this different from the other 2??
Ever played with sand??
Origins of Sedimentary Rock
 Erosion-wind, H2O, ice, sunlight, and gravity cause rocks to
fragment- sediment
 Sediment will deposits into layers
 Will compact with other layers forming on top of them –like
layered cake
 Minerals dissolve together-can form cement
 Sedimentary rocks form near the Earth's surface or
at it
 Doesn’t need heat and pressure to make this rock
 Sedimentary rock have layers = strata
 Can easily see when driving through certain parts
of the country
Composition of Sedimentary Rock
 Clastic
 Rock/mineral fragments cement together
 Minerals-Calcite/Quartz
 Can be coarse, medium, fine-grained texture
 Chemical
 Minerals- crystallized out of a solution-sea
water
 As rain makes its way to the ocean/river it
dissolves rock/fragments
 In the water the minerals can crystallize and
make this rock
 Organic
 Remains of once-living plants + animals
 Most limestone forms from fossils/remains-even coral
 The remains will cement together
 Coal-forms underground from plat material buried
beneath sediment, pressure and heat will be applied over
yrs. To get coal
Sedimentary Rock Structures
 Stratification
 Sedimentary rock is arranged in layers
 Each strata differ from each other in minerals, size, and color of
sediment
 Ripple marks
 S. rocks can record motion of wind, water- lake,
oceans, river, and sand dunes
 Mud cracks
 Fine-grained sediments at the bottom of shallow body
of H2O are exposed to air and dry out
 So can see where ancient lakes, streams, oceans
where once at
THE END!!