9. Conglomerate – cemented sand, silt, and pebble sediments. If large fragments are angular this rock is called a breccia. Sandstone – cemented quartz sand grains. Feels gritty. Unfilled spaces between grains make most sandstones porous and permeable to water.
10. Shale – clay and silt sized particles lithified by dehydration and compaction. Note the cleavage at bedding planes. Thumps when you tap it with a nail and, moistened, it smells like damp earth. Bedding planes
11. Sandstone in the Pinnacle Desert, Australia Photo used with permission from Mike Jarvis, Naperville Central HS, Naperville, IL
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14. Rock salt , the mineral halite (NaCl), left as an evaporite as a shallow sea evaporated. Alabaster , the mineral gypsum (CaSO 4 ), also an evaporite.
15. Compact (or precipitate) limestone , the mineral calcite (CaCO 3 ), precipitated from sea water as evaporation increased concentration. Many cavern systems are formed in this type of limestone.
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17. Coquina – cemented aggregate of geologically modern shell fragments. Fossiliferous limestone – a cemented aggregate of original shell fragments, molds, and casts of ancient marine organisms. Note fossil mold of a shell in this specimen.
18. Peat , a mass of matted together plant material covered by H 2 O, which impedes decay. H 2 and O 2 are lost, concentrating carbon. Lignite , so called “brown coal”, a soft coal that forms when peat is compressed and aged, about 40% carbon.
19. Bituminous coal – soft coal formed when lignite is compacted and altered for millions of years, about 85% carbon, this coal is the most commonly mined and used for a fuel.
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21. Rock Stratification (layering) Bryce Canyon, UT Photo used with permission from Mike Jarvis, Naperville Central HS, Naperville, IL
22. Ripple marks caused by wave action on the sandy bottom of a shallow bay Almost identical ripple marks on the surface of a sandstone millions of years old.
23. Mud cracks in drying mud Mud cracks preserved on the bedding surface of a shale.
24. Groundwater dissolves hollow spaces in sedimentary rock, typically limestone, and mineral material is deposited inside the hollow with crystal points growing toward the center. Geode Thunder Egg
25. Cross-bedding at Checkerboard Mesa Zion National Park, UT Photo used with permission from Mike Jarvis, Naperville Central HS, Naperville, IL
26. Dinosaur skeleton preserved in sedimentary rock - China Photo used with permission from Mike Jarvis, Naperville Central HS, Naperville, IL
![Sedimentary Rocks ,[object Object]](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)