الإ ختبار

1. Where does sedimentary rock almost always form?
Under water

2. For any rock to become sedimentary rock, what process must happen to it first?
It must be weathered into small pieces or a chemical solution

3. What are clasts?
Small bits and pieces of weathered rock

4. What is Clastic sedimentary rock?
Rock made of bits and pieces of other rocks

5. A Clastic sedimentary rock composed mostly of sand is called ________.
Sandstone




6. What is weathering?
The natural breakdown of rock


7. What are the 3 types of weathering?
Mechanical
Biological
Chemical

8. How do we know mechanical weathering?
Movement that is not caused by plants or animals without chemical change for rock

9. How does “abrasion?” wear away rock?
Water or wind rubs particles of sediment against the rocks to wear them down


10. Does air or water abrasion do more weathering?
WATER

11. How do landslides cause rock to weather?
Falling rocks break when they hit the bottom

12. What is “unloading,” and how does it affect rock?
When the overlying rock weathers away it’s weight is unloaded from the lower rock allowing it to expand and crack

13. What is “Chemical Weathering?”
Rock breaking down due to exposure to chemicals
14. How does acid rain affect chemical weathering?
It dissolves certain types of rocks


15. What is a “sinkhole?”
The top of a cave that has collapsed to the surface


16. What types of rock tends to support sinkholes?
Carbonates, which are:
Limestone


17. What is a famous and beautiful example of chemical weathering?
Luray Caverns
Mammoth Cave


18. What can oxygen bring about in the rock?
Rusting, which expands and weakens the rock

19. What is “Biological Weathering?”
Rock breakdown that is caused by plants or animals


20. How do lichens start the weathering process in rocks?
They produce an acid that etches the rock and makes it ready for mosses to grow there

21. How does moss affect the weathering process?
It holds rainwater that may be acidic, & builds up soil for plants with strong roots

22. What is “tallus”?
A slow motion avalanch of small rocks down the side of a mountain. They slowly grind each other to bits


23. What rock is the first rock in the “Rock Cycle?”
Igneous Rocks were the first rocks on Earth


24. Why is one characteristic not enough to identify a mineral or rock?
Because many minerals share many of the same characteristics


25. What is the main thing that tells you when weathering is chemical?
Chemical reactions weaken or dissolve the rock


26. A Clastic sedimentary rock composed mostly of clay is called ________.
Claystone or shale


27. A Clastic sedimentary rock composed mostly of silt is called ________.
Shale

28. A Clastic sedimentary rock composed mostly of sand and rounded pebbles is called ________.
Conglomerate

29. A Clastic sedimentary rock composed mostly of sand and small broken rocks is called ________.
BRECCIA


30. What makes a sedimentary rock Organic?
Some part of it was once alive


31. An organic sedimentary rock composed mostly of tiny shells is called ________.
Coquina

32. An organic sedimentary rock that is made from disolved shells an deposited chemically by precipitation is called ________.
Limestone


33. Rock that was precipitated by evaporating water and was never alive is called _________ sedimentary rock.
Chemical


34. What are 2 examples of chemical sedimentary rock?
Rock salt and Gypsum


35. What is peat made of?
Moss



36. What is all coal made of?
Moss
Ferns
Ancient conifers


37. The first stage of coal that is a true rock is called _____________ or brown coal
Lignite


38. The second stage of coal that is a true sedimentary rock is called _________ Coal
Bituminous


39. Why must sedimentary rock always cover coal?
It provides the pressure that causes the non-carbon molecules to be driven out of the plants


40. What are the three most common evaporite minerals?
Halite
Gypsum
Anhydrite