notes

1. Rocks
❏ Solids that are composed
of 2+ minerals
-a few are made of
remains of living
organism

2. Types of Rocks (3) ❏ Classified according to how they
are formed
❏ Igneous
❏ Metamorphic
❏ Sedimentary
❏ Arrow is the process that forms
the rock
❏ The box is the rock form/group

3. How do Igneous
Rocks form?
❏ Form from liquid rock (magma)
❏ Rate of cooling determines texture
❏ Intrusive: Slow cooling,
Coarse texture
❏ Extrusive: Fast cooling
(usually on Earth’s surface),
Smooth /Fine texture
❏ Color is determined by the
minerals present.
❏ Felsic: Light color (pink, white
or grey)
❏ Mafic: dark in color (black or green)
❏ Volcanic: cooled fast above
ground
❏ Vesicular: contains gas pockets
(always extrusive)

4. Igneous Rock
Identification
Chart
An x-ray is the only way to tell the
difference between Obsidian and
Basaltic Glass

5. Sedimentary Rocks
(Form 3 ways)
-can be uniform or not
❏ Clastic (fragmental): rocks made
up of cemented, weathered
remains of other rocks
❏ Chemical Precipitates: formed as
a result of water evaporation. The
water leaves behind dissolved
solids (evaporites).
❏ Formed in lagoons and
groundwater
❏ Bioclastic: Formed from the
remains of living organisms,
contains FOSSILS!

6. Clastic Rocks (an analogy)
Sediment Sedimentary Rock

7. Chemical Precipitates
Salt Water Salt

8. Bioclastic (how coal is formed)

9. Sedimentary Rock Chart

10. Metamorphic Rocks
❏ These have changed from
other types of rocks
❏ Resulted from varying
degrees of heat and pressure
❏ Any type of igneous or
sedimentary rock can be
altered to become a
metamorphic rock
❏ Regional Metamorphism: foliated
rocks with mineral alignment or
banding this is the result of HIGH
pressure
❏ Form close to magma or plate
boundaries
❏ Contact Metamorphism: non-
foliated rocks formed from high
heat associated with contact with
magma
❏ Magma bakes the rock

11. Regional
Metamorphism
Rock goes from the top picture to the bottom

12. Metamorphic Rock Textures
❏ Foliated: mineral alignment, but
not layered
❏ It’s like squishing a
marshmallow between 2
graham crackers (Mmm)
Non-foliated: crystalline, glazed or
frosted appearance

13. Metamorphic Rock Identification Chart

14. Mineral Identification
Using the Properties of Common
Minerals Chart and following the
steps to the right will help you to
identify each mineral
*The distinguishing characteristics
column is VERY important for some
minerals
1. Luster:
a. Metallic: shiny metal
b. Nonmetallic
2. Hardness: resistance to scratching (Mohs
scale of hardness)
a. Fingernail = 2.5
b. Glass = 5.5
c. Steel Knife = 6.5
3. Cleavage or Fracture
a. Cleavage breaks along flat surfaces
b. Fracture splits without flat surfaces
4. Streak
a. Scratch the mineral on a ceramic
plate
b. Does the color on the streak plate
match the minerals color
5. Distinguishing Characteristics
a. This column has more information,
Check it OUT!