Rocks, Rock!
Mineral and Rock Vocabulary
Rock
• Rock is a solid mixture of crystals of one or
more minerals
• Rocks are categorized into 3 types on how
they are made
• Each rock in each category is classified
(named) by its TEXTURE and COMPOSITION
Igneous Rock
• Definition: Igneous rock is rock formed when magma
cools and solidifies into rock. (Rock from Volcanoes)
• Extrusive vs. Intrusive
– Intrusive Rock- When magma cools slowly under the
earths surface- causing large grained rocks
– Extrusive Rock- when magma erupts from a volcano it is
called lava, lava cools quickly causing fine (small) grained
rocks
• Felsic vs. Mafic
– MAFIC: Low silicon level rocks which are dark colored rocks
– FELSIC: High silicon level rocks which are light colored
rocks
Igneous Rock Examples- special
features
Felsic-
Mafic
Extrusive
Grain size-formed outside
quickly
Pumice
Obsidian
Basalt
Intrusive
Grain Size-formed inside
slowly
Granite
Gabbro
Review Time
• Turn to your neighbor and explain to him/her
what igneous rock is, and what the 4 types of
igneous rock are.
• How are rocks grouped (3 ways)
Quiz Time
• Which of the following best describes this rock
•
•
•
•
A Extrusive Mafic
B Intrusive Mafic
C Extrusive Felsic
D Intrusive Felsic
Sedimentary Rock
• Definition: Rocks that form when sediments
are compacted and cemented together
• Sediments are small fragments of rock –like
sand
• Rocks must go through several steps before
they become sedimentary
– Weathering
– Erosion
– Deposition
– Compaction and Cementation aka lithification
Sedimentary Rock Examples and
Clastic- rock
special
features
fragments
Chemical- minerals
and water
Organic- Made from
shells, skeletons,
fossils and minerals
Conglomerate- large fragments
Chemical limestone
Sandstone medium
sediment
Fossiliferous
limestone
Quiz Time
•
•
•
•
•
What is the best description of this rock?
A Clastic Sandstone
B Clastic Conglomerate
C Organic fossiliferous limestone
D igneous rock
Review Time
• Turn to your neighbor and tell them the
difference between sedimentary and igneous
rock.
Metamorphic Rock
• Definition: Rock that forms when the texture
and composition of preexisting rock changes
due to heat or pressure.
Fast Five Quiz
• Go as quickly, and as safely as you can to the
right corner. The following words are
associated with what kind of rock?
• A Sedimentary Rock
• B Metamorphic Rock
• C Igneous (Extrusive)
• D Igneous (Intrusive)
Energy and the Changing earth
• We talked about how energy changes in food
pyramids and food webs, and how that affects
living organisms. Refresh:
___________ _____________________________
• now lets talk about energy and how earth’s
rocks are affected- what is
chemical/mechanical energy?
Rock cycle
Decision Time
• Where and how can you see
chemical/mechanical energy in this new
system?
• Now that you have seen some examples of
rocks, and you have seen the rock cycle. If you
wanted to build a strong, long lasting
monument to yourself for the world to see
what type of rock would you use and why?
Weathering
• Definition: breakdown of rock into smaller and
smaller fragments.
Mechanical Weathering
• Mechanical weathering: The breakdown of
rocks by physical means- by ice, wind, water
force, gravity, abrasion
Chemical Weathering
• Chemical weathering: the breakdown of rocks
by chemical means into new substances- by
soil, water, weak acids,
Erosion
• The removal and transport of sediment and
material by wind, water or ice (glaciers)
Deposition
• Definition: Depositing sediments, or the laying
down of sediments from movement.
Compaction and Cementation
• Definition: The squeezing and solidifying
(gluing) of sediments together to finally
become rock.
Magma