es chap 5 & 6: rocks objectives identify and explain...

ES Ch 5 & 6 Rocks Outline - 1 - 10/14/2012

ES Chap 5 & 6: Rocks Objectives 1. Identify and explain characteristics of igneous rocks. This means that if I am given an igneous

rock I: a. Can use grain size to identify a rock as intrusive, extrusive, or porphyry. In addition, I can

discuss how the rate of cooling is related to grain size. b. Can use color to identify a rock as felsic, intermediate or mafic. c. Combining grain size and color (as described in a & b), I can use Table 5-2 on page 107 to

name the rock. d. Use Table 5-2 page 107 to identify a rock if I am given the percent composition of a rock.

i. Understand which minerals and rocks in Table 5-2 are high in silica, iron and magnesium.

e. Discuss the factors that affect how rocks melt & crystallize f. Describe uses of igneous rocks. g. Rocks that may be samples to identify on the exam: obsidian, pumice, rhyolite, granite,

basalt, gabbro.

2. Identify and explain characteristics of sedimentary rocks. This means that I: a. Can describe and list in order the steps that form clastic sedimentary rocks: Weathering (both

physical and chemical), erosion, deposition, burial, lithification, cementation b. Can use information about ripple marks and fossils to infer what the past environment is like. c. Can identify a rock into one of the following subgroups; clastic, organic, chemical d. Can use the Law of Superposition to determine which rock layers are older or younger. e. Describe uses of sedimentary rocks. f. Explain miscellaneous terms such as porosity g. Rocks that may be samples to identify on the exam: conglomerate, breccias, sandstone,

limestone, coal

3. Identify and explain characteristics of metamorphic. This means that I a. Can identify a rock into a metamorphic subgroup; foliated vs. non-foliated b. Explain the formation of metamorphic rocks. c. You will be asked to identify a rock as metamorphic and then as foliated or non-foliated, but

you will not be asked to give it a specific name.

4. Understand how rocks continuously change from 1 type to another in the rock cycle.

5. I can identify a given rock sample into: a. One of the 3 main types of rock described above: igneous, sedimentary or metamorphic. b. Into the appropriate subgroup as described above.

Sec 5.1 Classifying Igneous Rock 3 types of Rock: 1. Igneous: Formed from _______________________ ___ of ______________

a. Lava is magma that reaches & flows onto Earth’s ________________

2. Sedimentary: Formed from sediments ________________________________ together

a. Sediments: Small pieces of _____________________________________

3. Metamorphic: Formed when a rock changes into a _________________________ due to extreme _____________________________________________


Igneous Rocks: 1. Extrusive rocks: Fine (_________) grained rocks due to _____________ cooling on Earth’s ______

a. Examples: ____________________________________

2. Intrusive rocks: Coarse (_________) grained rocks due to __________ cooling _______the surface

a. Examples: The most common intrusive rock is ______________________ Magma: 1. Composition:

a. Mix of _____________ rock, gases, and mineral crystals b. Elements common in magma are the major elements found in Earth’s crust: ______________ c. Most common compound: ____________________

2. Types: Based on the amount of__________ Magma Type Amount SiO2 Relative color of

rocks when cools Special Characteristics

1. Rhyolitic (Granitic)

2. Andesitic

3. Basaltic

3. Origin:

a. Heat of 800 – 1200oC to ____________ b. This temperature is found in the ______________________ and _____________________

What heats the upper mantle & lower crust?

c. Partial Melting is due to minerals with ___________________________ points

i. Causes a slushy mix of _____________ rock & ____________ crystals Section 5.2 Classifying Igneous Rocks 3 Classifications of Igneous Rock: based on the __________________________ of the rock 1. Felsic 2. Intermediate 3. Mafic


Igneous rock type

Felsic Intermediate Mafic

Type of Magma

Silica (SiO2 ) content

Relative color

High in:

Texture

Rock E

xa

mp

les

Extrusive

Intrusive

Main observations for igneous rock identification: 1. Color: _____________ vs. ________________ 2. Grain size: ______________ vs. _______________ Special IG rocks: 1. Porphyritic texture: Mixture of ______________________ grains

a. Complex cooling history: 1. 1st ____________cooling deep in Earth-forming the _____________crystals. 2. 2nd ___________ cooling of remaining magma due to sudden ________________or

_______________ close to the surface

2. Obsidian: “Black glass”

a. Cooled ________________ that ______________ crystals are formed: ________________

3. Pumice: 50% holes due to escape of trapped ____________

a. Formed from _____________ magma b. Used for abrasive polishing mixtures and cleansers

Igneous Rocks as Resources 1. Building materials: ________________ & ___________________ to weathering 2. Ore deposits: _______________ of ______________ substances within the rock

a. Gold, silver, lead, & copper are not in compounds that form minerals, but they are found as ________________________________________


b. ________________________ c. Found in _________ or __________________

i. Formed when liquid magma fills ________________ in other rocks & cools

Sec 6.1 Formation of Sedimentary Rocks Steps to Form Sedimentary Rocks: 1. Weathering: Breaking down & ________________ of rocks into smaller pieces (called _________

sediments which vary in size) a. Physical or mechanical causes of breakdown include: _____________________________

________________________________________________________________________

b. Chemical causes include _________________ of rocks by _________ rain or chemicals 2. Erosion: ___________________________________of sediments to a new locations

a. Possible means: __________________________________________________________

3. Deposition: ___________________ or ________________ of sediments on the ground or bottom

of bodies of water 4. Burial: Becomes _________________________ beneath more & more sediments 5. Lithification: means “making of _______________” and has 2 parts

a. Compaction: Bottom layers of sediment are ______________ together by______________

of upper sediment layers b. Cementation: Sediments are _____________________ or ____________ together by

minerals in the water that _____________________ c. Summary: Lithification turns ___________________ into _________________________

Features of Sedimentary Rocks: 1. Layers (AKA beds)

a. Law of __________________: __________ rocks on the ________ if layers are undisturbed

i. Exception occurs when layers are overturned by _______________________ forces b. The following always form on the top of a layer. If they are found on the bottom instead, it

indicates that layers have been overturned: ________________________________ 2. Sedimentary rocks usually form in _______________________ 3. Sedimentary rock is _______________________ rock on the ______________ (not in crust) of Earth

a. Igneous rock is the most common rock in the CRUST, but it is buried. Most igneous rock is formed underground, not through lava on surface.


Evidence of Past Life 1. Fossils: Preserved __________________________________ of once-living organisms

a. Only found in ____________________rocks. WHY? b. During lithification, parts of organisms are replaced by _______________ & turned into rocks

Sec 6.2 Types of Sedimentary Rocks 3 main groups of sedimentary rocks: 1. Clastic 2. Organic 3. Chemical Sedimentary Group

Made from Subgroups & examples

Clastic

sedimentary rock

3 clastic subgroups based on grain size: 1. Coarse-grained: ________________grains or larger

a. Due to high water flows & speeds which can carry large pieces: ____________________________ _____________________________________

2. Medium-grained: _____________-sized grains

a. Form _____________________ which has

high porosity (incomplete cementation leaves ________________________between grains)

b. Valuable reservoirs of ______________________

3. Fine-grained: ______________________

a. Low porosity (barrier)

Organic

Examples: 1. Limestone: _______________________ 2. ___________: rock from buried swamp plants

Chemical

Example locations: 1. Coast of _______________ or the _________________


Importance of Sedimentary Rocks: 1. Fossils tell about ____________________________________

a. Type of area and types of organisms: ____________________________

2. _____________________ tell the direction of ________________________ in the past: a. Symmetrical ripple marks:

i. Both sides of ripple have same shape

ii. Indicates _______________________________ wave action b. Asymmetrical ripple marks:

i. 1 side is gently sloped & other side is steep

ii. Indicates ____________________ wind or wave motion

iii. Examples: _______________________________ 3. Energy

a. ____________________ b. Reservoir for ________________________when _________________ (open space) present

4. Limestone to make ____________________ Sec 6.3 Metamorphic Rocks: ________________ rocks turned into a __________ rock type Formation of Metamorphic Rocks 1. Pressure & temp ___________________with depth

a. If hot enough to melt, _____________________ rocks are formed b. If not hot enough to melt, but enough ___________________ to change the rock,

_______________________ rock is made

2. Heat is due to ________________________ or nearness to _____________________ intrusions 3. Pressure is due to the pressure of ____________________________________ of mountain building 4. Metamorphic rocks may be

a. _________________(alternate light & dark bands) due to ____________with ____________ i. Lines may be straight or wavy ii. Example: Gneiss is formed from the igneous rock _______________

b. ___________________

i. Example: Marble is formed from the sedimentary rock ______________________


The Rock Cycle:

1. Is the ____________________________________________ of rock 2. Based on how new rock type is formed. 3. Following is an example of the possible changes the igneous rock granite could undergo. When it is:

a. Weathered into ___________________________ ⇒ new ______________________ rock is formed

b. Buried (but not melted) where __________________ affect it ⇒ new ___________________ rock is formed

Comparison of the Characteristics of the 3 rock types:


Computer Review: http://www.glencoe.com/sec/science/earthscience/index.html a. Chapter Resources b. Unit 2 c. Chapter 5 and Chapter 6

Diagram-Igneous Intrusions #2


WS: Rock Record, Figure #1




WS: Rock Record, Multiple Choice Figure

es chap 5 & 6: rocks objectives identify and explain...

Documents