1. SEDIMENTARY ROCK

2. BIG Idea
Most rocks are formed from pre-existing rocks through external and internal geologic processes.

3. The formation of sedimentary rocks begins when weathering and erosion produce sediments…

4. Sediments: rock, minerals and organic matter broken into fragments

5. Weathering: the breakdown of rocks and minerals at or near the Earth's surface into smaller pieces (sediments).

6. Erosion: the removal and transport of broken down sediment

7. HOW are sediments transported?

9. Wind
Moving water
Gravity
Glaciers

10. How sedimentary rocks form:
COMPACTION: air and water is SQUEEZED out of the sediments
CEMENTATION: mineral growth GLUES sediment grains together into solid rock 10

12. FORMATION OF SEDIMENTARY ROCKS
SEDIMENTARY ROCKS ARE EITHER CLASTIC, CHEMICAL or ORGANIC (BIOCHEMICAL)…
1. CLASTIC – MADE UP OF FRAGMENTS FROM PRE-EXISTING ROCKS

13. a. CONGLOMERATE: MADE OF ROUNDED PEBBLES

14. b. BRECCIA: FRAGMENTS THAT HAVE SHARP AND ANGULAR EDGES

15. c. SANDSTONE: MADE OF SAND GRAINS CEMENTED TOGETHER

16. d. SHALE: CLAY-SIZED PARTICLES CEMENTED TOGETHER

17. Siltstone: another fine-grained sedimentary rock

18. 2. CHEMICAL (NON-CLASTIC): ROCK FORMED CHEMICALLY OR ORGANICALLY FROM MINERALS THAT PRECIPITATE (separate) FROM WATER (solution)

19. EVAPORITE: FORMED FROM MINERALS LEFT AFTER WATER EVAPORATES
ROCK SALT (HALITE)

20. rock gypsum
chert (flint)

21. fossiliferous limestone
3. ORGANIC (biochemical) – MADE UP OF ORGANISMS
coal / peat
chalk
fossiliferous limestone

22. coquina

23. Porosity: percentage of open spaces in a rock or sediment

24. FACTORS THAT INFLUENCE POROSITY:
(a) SORTING: amount of uniformity in particle size
HIGH pore space
LOW pore space

26. (b) SHAPE: rounder particles = more porous
(c) PACKING: loosely packed = more porous

28. Permeability: how freely water flows through open spaces in a rock (the pores must be connected)
Impermeable – water can NOT flow through

29. Can something be porous but impermeable?
The cork end is red because the wine went into it. Does this mean it is porous?
If you turn the bottle upside down will it leak? Is the cork permeable?

30. SEDIMENTARY ROCK FEATURES
1. STRATIFICATION: LAYERING DUE TO THE CHANGE IN THE KIND OF SEDIMENT

31. 2. RIPPLE MARKS: FORMED BY THE ACTION OF WIND AND WATER ON SAND

33. 3. MUD CRACKS: WHEN MUD DRIES

35. 4. FOSSILS: THE REMAINS OF ANCIENT PLANTS OR ANIMALS