Introductory Geology – II (Geology 1122)

Final Exam

Summer Semester 2024

July 15, 2024

Review for Final Exam

Useful information. The final exam will be available July 24 (10:45 am to 1:15 pm). Please clear your calendar to take the test at this time.

The exam will have 75 questions. The attempt will be to balance the topics of the questions equally through the course. Some questions will test integration of concepts from different parts of a course (e.g. glaciers, climate change, weathering). Topics that I have tested on previously and topics given in the review sheets are fair game. Questions will be typically drawn from these topics.

If any enrolled student misses taking this final exam at the scheduled time, then a make-up will be administered only if it can be determined that you had a valid reason (health, accident, court summons) for missing this exam and the instructor was contacted in a timely way. The deadline for taking any late exams is close of business July 26 close of business. Otherwise a zero will be entered for your score of the final exam. The instructor will make all reasonable effort to score any late exams before the deadline to submit grades.

Select topics are given below.

Climate Change and Anthropogenic effects. Describe the greenhouse effect. What are the predominant greenhouse gases on Earth? What are anthropogenic sources of these greenhouse gases? What is the present concentration of CO₂? Preindustrial CO₂? Name short term changes and long term changes impacting climate. Define Anthropogenic. Function of stratospheric ozone? Why is methane a more potent GHG? Why are global circulation models (GCM) important?

Biography of Earth. Name Eons (their characteristic forms of life, characteristic rock/tectonic/mountain building events, atmosphere). Domains of life. Mass extinctions (end Mesozoic and End Paleozoic, causes). How did earth’s atmosphere gain in Oxygen in the Precambrian? Transgressions, how and when? Cambrian explosion. Rates of evolution, natural selection. Uniformitarianism? Age of Earth? Also, evolution, natural selection.

Energy: Nuclear, Fossil Fuels. Describe fission and how sustained. How clean electricity is produced from nuclear energy. Source materials for crude oil, natural gas and coal. Which fuel is the dirtiest and why? Longevity of fuel resources. Consumption of crude oil world-wide, and nationally, on a per-day basis. Longevity of fossil fuels. Temperatures needed to generate: biogenic gas, crude oil and natural gas, thermogenic gas, bituminous coal, anthracite. Name examples of good traps for crude oil and natural gas. What makes these traps good traps? Differentiate petroleum source rock from petroleum reservoir rock.

Glaciers. Milankovitch orbital variations. Characteristic landforms caused by glaciers. Advance and retreats of glaciers, why? Necessary factors (3) needed to form glaciers.

Geologic time. Relative geologic time (Steno’s Laws, be able to work out a simple cross section), absolute geologic time (half-life, parent, daughter calculations). Key dates (age of earth, oldest rock, age of Lucy, age range of Eons). Uniformitarianism.

Which is older: Pluton M, or Limestone X?

Which is younger: Fault J, or Pluton M?

Order the following from oldest to youngest: Conglomerate D, Fault J, Limestone X, and Pluton M?

New Problem 2: Given an atom with 20,000 radioactive parent atoms, Po, calculate P, D and P+D after each half-life. If the half life is 50 million years, how old is the rock having 1,250 P remaining. What is D after two half-lifes? Complete this table.

Surface and Groundwater. Measurement of stream discharge (product of the stream cross section area and stream velocity, state the equation and units of each term.). Hydrologic cycle. Aquifers. What are the relative amounts of the following reservoirs of water: Ocean, ice/glacier, groundwater, surface water. Define Water table. Permeability, porosity, Total dissolved solids. Water doctrine (appropriation, riparian). Sources of total dissolved solids? If you dissolve a limestone, what elements are added to groundwater from weathering limestone? [Comment, not trivia, this reaction is a source of hard water.]

New Problem 3. For the next three questions consider the following statement about an unconfined aquifer and water well levels. You have drilled two wells A and B into an unconfined aquifer. At well A, the water table is 450 feet. The water table at Well B is 440 feet. Both elevations are relative to mean sea level. The distance between Well A and Well B is 100 feet. Well A is located due north of Well B. Answer the next three questions.

Draw a sketch map of the locations of the wells. Note the elevations of water table at each well. note distance between wells. Answer the following questions.

What is the hydraulic gradient of this aquifer?

a) 0.05 b) 0.1 c) 0.5 d) 1.0 e) 5.0

If the hydraulic conductivity of this unconfined aquifer is 10 feet/day, then how fast is water flowing in this aquifer?

1. 0.5 feet/day. d) 10 feet/day.
2. 1.0 Feet/day. e) 50 feet/day.
3. 5.0 feet/day.

What is the direction of water flow?

1. West to East. c) North to South.
2. East to West. d) South to North.

How long does it take for water to move from one well to the other?

1. 0.1 day. b) 1.0 days. c) 10 days. d) 100 days. e) 1,000 days.

Rock Cycle. Be able to draw a rock cycle. For thought, what drives the rock cycle processes above earth (erosion)? Beneath earth (melting, metamorphism, solidification)?

New Problem 4. Draw and label correctly the Rock Cycle.

Soils. Name horizons in a soil and the process forming each soil horizon. What are the controls the thickness of a soil (name three)? Why is a desert soil thin? Why a Tropical soil thick? How is soil eroded? How might global warming lead to soil loss?

New Problem 5. Calculate the Surface area of a cube having a length of 3m. Why does surface area increase as you break a rock to smaller pieces (Fig B.7)? Can you name a resistant rock to weathering? Name a rock that breaks down easily in weathering. Processes of Physical weathering. Processes of chemical weathering. Name them.

New Problem 6. There are 800 million tons of coal as reserve in the US. The consumption is 20 million tons/year. What is the longevity of this reserve?

New Problem 7. Calculate the recurrence interval for a stream having flooding at 20 years ago, 50 years ago, and 80 years ago. What is the probability of flooding given this RI?