1. Sedimentary Rocks
By Mr. Krall

2. Doth anyone have lotion?
Sedimentary Rocks
All rocks and minerals are worn down and broken up by weathering.
Doth anyone have lotion?
Acid rain is weathering this statue.
Weathering agents include running water, ice, temperature changes, wind, plant growth, animal activity, chemical reactions, and gravity.

3. Sedimentary Rocks
This tree’s growth is breaking the large rock into smaller pieces.
Changes in temperature with the help of water is classic Pennsylvania weathering. This is why our roads are full of potholes every spring.
All these agents work to break up rocks and minerals into smaller pieces called sediments.

4. Sedimentary Rocks
Sediments are broken down pieces of rocks and minerals.
Examples are rock fragments, mineral grains, and even bits of plant and animal remains.
This pile of sediment includes pieces of rocks and minerals, as well as a variety of shells.

5. Sedimentary Rock
Sedimentary Rock can form in two ways. Compaction Cementation

6. Sedimentary Rock
Compaction – when sediments pile on top of each other, the weight of the layers on top, crushes the layers on the bottom, turning them into solid rock.
SQUASH
Layer after layer of sedimentary rock, a common sight in Pennsylvania.

7. Sedimentary Rock
Cementation – Minerals dissolved in water become a “glue” that turns sediments into rock as the water evaporates.

8. Sedimentary Rock
Sedimentary Rocks are classified in 2 groups: Clastic Chemical/Organic

9. Sedimentary Rock
Clastic, sedimentary Rocks are made when sediments are compacted together. The sediments can be rounded or jagged, large or small.
Conglomerate is made of large, rounded sediments.
Breccia is made of large, angular, sediments.

10. Sedimentary Rock
Chemical sedimentary rocks form when dissolved minerals are left behind by evaporating water. Organic sedimentary rocks contain pieces of once living material.
Travertine is a chemical rock that forms from minerals dissolved in groundwater.
Coal is made of the remains of animals from long ago crushed into rock.