STUDY GUIDE FOR EXAM 2

 

IMPORTANT TERMS AND CONCEPTS

 

The following is a list of key terms and concepts that I expect you to know for exam 2. For each term you should know how it is defined, why is it important, and example(s) used in class.

 

 

 

Weathering

 

Weathering:

 

Mass wasting:

 

Erosion:

 

Mechanical weathering:

 

Chemical weathering:

 

Mechanical weathering processes (including definitions and examples)

           Unloading:

           Frost wedging:

           Biological activity:

Thermal expansion:

 

Chemical weathering processes (including definitions and examples)

           Dissolution:

           Hydration:

           Hydrolysis:

           Oxidation:

 

Variables controlling rates of chemical weathering

 

Weathering Stability Series:

 

How climate affects the dominant type of weathering processes

 

Role of climate in weathering feldspar

 

Role of climate in weathering a granite

 

Role of fractures in weathering

 

Examples of differential erosion in humid and arid climates

 

 

Sediments and Sedimentary Rocks

 

Types of weathering products:

 

Lithification:

 

Types of sediment and sedimentary rocks:

           Clastic

           Chemical

           Biochemical

 

Basis for classifying clastic sediments and sedimentary rocks:

 

 

Sedimentary texture includes:

 

 

Size Range

Particle name

 

Common sediment name

Sedimentary Rock

 

>2mm

 

 

 

 

 

 

 

 

1/16 à 2mm

 

 

 

 

 

< 1/16 mm

 

 

 

 

 

 

 

Significance of grain size (w/examples)

 

Significance of grain shape (w/examples)

 

Significance of grain sorting (w/examples)

 

Depositional environment:

 

Indicators of depositional environment preserved in the rock record include:

 

 

Types of chemical precipitants

           Biochemical (e.g…..

           Inorganic (e.g…….

 

Evaporite minerals (what are they, how do they form, and where do we find them):

 

Sequence of precipitation of evaporates from sea water

 

The “Bulls eye model” of evaporite formation

 

Mineral sources of N, K, and P

 

 

Sedimentary rocks you should know include:

 

1.  Conglomerate:

2.  Breccia:

3.  Sandstone:

4.  Mudrock (shale):

5.  Quartz arenite:

6.  Arkose:

7.  Coquina:

8.  Limestone:

9.  Chalk:

10. Chert:

11. Evaporites

 

 

Metamorphic Rocks

 

 

Metamorphism

 

Agents of Metamorphism

 

How does pressure and temperature vary with depth?

 

How does the Geothermal Gradient vary with geologic setting

 

Regional Metamorphism

 

Contact Metamorphism

 

Hydrothermal Metamorphism

 

How are metamorphic rocks classified?

 

What is metamorphic foliation and how does it form?

 

Why are some metamorphic rocks foliated and others non-foliated?

 

Slatey cleavage

 

Schistosity

 

Gneissic texture

 

What is the difference between bedding and foliation?

 

How does the texture (and resulting metamorphic rock) change as a shale is regionally metamorphosed?

 

What is a Metamorphic Aureole?

 

How do you tell a metamorphic rock from a non-metamorphic rock based on texture and composition?

 

What are Index Minerals and why are they important?

 

Metamorphic facies (including Hornfels, Greenschist, Blueschist)

 

What are Migmatites and how are they formed?

 

Protoliths (including typical protoliths for typical metamorphic rocks)

 

In what geologic settings do the different types of metamorphism occur?

 

Metamorphic rocks you should know (e.g. what do they look like, how do they form) include:

 

1. Slate

2. Phyllite

3. Schist

4. Gneiss

5. Marble

6. Quartzite

7. Migmatite

 

Telling Geologic Time

 

 

Principle of Superposition

 

Principle of Original Horizontality

 

Principle of Cross-Cutting Relationships

 

Significance of Inclusions

 

Types of Unconformity, including:

 

- Disconformity

 

- Angular Unconformity

 

- Nonconformity

 

Be able to reconstruct the sequence of geologic events from across section (ala extra credit)

 

Two methods of correlation are……?

 

Fossil

 

Index fossil

 

Paleontology

 

How are fossils used?

 

What are the characteristics of fossils that are good for determining the age of a deposit?

 

What are the characteristics of fossils that are good for determining environmental conditions?

 

Principle of Faunal Succession

 

What is the significance of overlapping Index Fossils?

 

How can index fossils be used to recognize unconformities?

 

Major intervals of geologic time, including:

Precambrian

Phanerozoic Eon

Paleozoic Era

Mesozoic Era

Cenozoic Era

 

What are the approximate ages of the boundaries of the Eras in the Phanerozoic Eon, and on what are these boundaries based?

 

What is the difference between relative and absolute age dating?

 

What are the different ways we can determine absolute geologic time, and what are the advantages and disadvantages of each?

 

How has global temperature and atmospheric CO2 changed in the last 1000 years and how do we know?

 

Radioactivity

 

- Alpha Emission Decay

 

- Beta Emission Decay

 

- Electron Capture

 

How does the atomic number and mass change as the result of different types of radioactive decay?

 

How does Carbon-14 form, how does it decay, and why is it important?

 

What is radioactive half-life and how is it calculated?

 

How can isotopic dating of igneous rocks tell us anything about the age of sedimentary rocks and the fossils they contain?