1. Minerals & Rock Unit Notes 7th Grade Science

2. Rocks
Are divided into 3 groups based on how they were formed
Sedimentary
Metamorphic
Igneous
Are made of one or more minerals

3. Continually changed by processes such as Weathering, Erosion
Do not stay the same
Continually changed by processes such as Weathering, Erosion
Compaction, Cementation, Melting, and Cooling.
                                   
                                      

4. Rocks can change to and from the 3 types
The Rock Cycle
Earth materials change back and forth among the different types of rocks.

5. Weathering, Erosion, Deposition, Compaction, Cementation
Igneous
(Granite #11)
Melting, Solidification
Weathering, Erosion, Deposition
Compaction, Cementation
Recrystallization
Melting,
Solidification
Recrystallization
Metamorphic
(Gneiss #14)
Sedimentary
(Sandstone #6)
Weathering, Erosion, Deposition, Compaction, Cementation

6. Processes that form Sedimentary Rock
Weathering: the breaking down of the Earth’s material by natural processes (Water, Wind, Ice, Chemicals, etc.) into smaller pieces or sediments
Erosion: weathered rock and soil particles are moved from place to place
Deposition: weathered sediments are laid down in a new location creating new landforms or rocks
Compaction: heavy sediments press down on the layers beneath
Cementation: dissolved minerals flow between the sediments and cement them together
Processes that form Sedimentary Rock

7. Processes that form Igneous & Metamorphic Rock
Melting: caused by heat and pressure around the rock to form magma
Solidification: magma cools and hardens
Recrystallization: while cooling, rock can develop crystals, depending on conditions
Processes that form Igneous & Metamorphic Rock

9. Complete the following:
Turn in your Rock Cycle Directed Reading & Earthquake/Volcano Test Corrections
Get the 2 Directed Readings from the table
Have something to write with
Clear off your table

10. Complete the following:
Turn in your Rock Cycle Directed Reading, Comic Strip & Earthquake/Volcano Test Corrections
Get the Igneous Rock Directed Reading from the table
Get out your Minerals & Rocks Notes
Have something to write with
Clear off your table

11. Igneous Igneous is Latin for “born of fire”
Formed from cooling magma or lava

12. Forms when magma cools and solidifies
Some reaches the surface of earth before cooling, other cools under the surface

13. Intrusive Extrusive Form below ground from magma
(Example: Granite)
Form below ground from magma
Usually has coarse crystals (grains) from cooling slowly
Some have large and small crystals
Form above ground from lava
Usually have small or no crystals from cooling quickly
Extrusive
(Examples: Pumice & Obsidian)

14. Into the Bedrock On top (Exit) intrusive extrusive (crystals)
(no crystals)

15. Bedrock
                  
Magma!

17. Complete the following:
Get out your Minerals & Rocks Notes
Get the Paper from the table
Have a Textbook
Have something to write with

18. Igneous!

19. But then the
EARTH’S elements
Will not leave
the ROCK alone!

20. Ice
Wind
Water
ice
wind
water

21. They break up the stone

22. One way Sedimentary Rock can be formed
Deposit & Compress the Sediments
One way Sedimentary Rock
can be formed
That ROCK
changed again!

23. Sedimentary Rock
Formed from sediments (rock fragments, mineral grains, animal and plant remains) that are pressed or cemented together or when sediments precipitates out of a solution.
Sediments are moved by wind, water, ice, or gravity.

24. The heavy sediments press down on the layers beneath (Compaction)
Water or wind breaks down (Weathering), moves (Erosion), and deposits sediment (Deposition)
The heavy sediments press down on the layers beneath (Compaction)
Dissolved minerals flow between the sediments and cement them together (Cementation)
                                        

25. Sedimentary Rocks & Fossils
Deposited sedimentary rocks form horizontal layers called STRATA.
Process of arranging sedimentary rocks into layers is STRATIFICATION
Scientist know that the layers and fossils on top are YOUNGER than the fossils in lower layers
 Law of Superposition
                                        

26. Types of Sedimentary Rocks
Clastic: made of broken pieces of other rocks.
Organic: remains of once living plants and animals are deposited in thick layers called fossils
Chemical: minerals dissolved in lakes, seas, or underground water
Limestone made when calcite precipitates from sea water
Rock salt made from evaporation of sea waters
Types of Sedimentary Rocks

27. The Rock Cycle
Igneous
Metamorphic ?
Sedimentary

28. The Rock Cycle
Igneous
Metamorphic
kinda
melted
squished
Sedimentary

29. Bands (can) Form
                                                
                                  
Metamorphic
means
“changed”
Metamorphic!

30. Metamorphic Rocks Rocks changed due to intense heat and high pressure
“Meta-” means “changed” and “-morphosis” means “shape” in Greek
Igneous, Sedimentary and other Metamorphic rocks can change to become Metamorphic rocks

31. How Metamorphic Rocks Change
Pressure from overlying rock layers
High heat, but not enough to melt the rock
Rocks may be flattened or bent or atoms may be exchanged to form new materials.
Think of metamorphic rocks as a squished peanut butter and jelly sandwich in your lunch.
How Metamorphic Rocks Change m

32. Types of Metamorphic Rock Foliated
Has visible parallel layers or bands you can see
Example: Gneiss formed from rearrangement of minerals in Granite into bands
Not layered & no bands are formed
Example: Marble formed from Limestone
Non-Foliated

33. The Rock Cycle
Igneous
metamorphic
Sedimentary

34. The Rock Cycle
                                                          
                                             

35. always changing…

36. Volcano
Roots here!
Youngest
Rocks
Here !
Oldest Rocks
Here !