Geos/Anth 462/562 Homework Assignments

1 Pleistocene Study
2 Holocene Study
2 Holocene Study 2
3 Pluvial History
4 Floods
5 Pleistocene Extinctions
6 Calibration
7 Non Marine
9 Dendrochronology
10 Radiometric
11 Chronologic Techn.
12 Paleomagnetic Chronology
13 Lichenometry
14 Rock Varnish
18 Paleoclimate
18 Paleoclimate 2
19 Clim. Geological
20 Clim. Solar
20 Clim. Solar 2
21 Clim. Astronomical
22 Clim. Atmospheric
22 Clim. Atmospheric 2
23 Volcanic Eruptions
24 Sediments
25 Caves
25 Caves 2
26 Palynology
27 Macrofossils
27 Macrofossils 2
28 Packrats
29 Charcoal
29 Charcoal 2
30 Phytoliths
31 Invertebrates
32 Soils
33 Historical Records
34 Archeology
35 Periglacial
36 Biogeography

QUATERNARY LITERATURE JOURNALS



This exercise will acquaint you with some of the literature of Quaternary Paleoecology.

Search through the UA library listing of online journals such as Quaternary Research. (The Dept. of Geosciences Antevs Library home page also lists these.) Look through several journal articles and copy down 20 Quaternary-chronology terms you find (in titles, abstracts, text, tables, or figures), that also occur in the notes for lectures 1 and 2. (Quaternary, Pleistocene, Wisconsin, Farmdalian, Early Pleistocene, Eamian, etc.) Select one sentence that illustrates one of these terms, and write a formal reference for the journal it comes from. Be sure to follow the format used in this class in the REFERENCES (use this *format). (You can't just cut-and-paste.) Look up the call letters for that journal in the UA Library Catalog.

Submit the answer by email to Owen Davis odavis@email.arizona.edu
  1. list of 20 Quaternary-chronology terms ___ (4 pts)
  2. one sentence from an article using one of these terms ___ (1 pt)
  3. a formal reference journal from which sentence is copied ___ (4 pts)
  4. spelling, punctuation, neatness ___ (1 pt)

    10 points total

HOLOCENE STUDY



Various terms have been proposed for the "climatic optimum (an informal European term)" of the Holocene. They all are based on evidence that climate has been warmer sometime since the last ice age. This assignment is to locate two of these terms in the literature and send me the name and age range for each. The names are: Atlantic, Xerothermic, Altithermal & Hypsithermal. You can use one name twice as long as it has a citation from a completely different group (no authors the same). If it's a single date (not a range) it doesn't count. Send the two names and age ranges to odavis@email.arizona.edu by the due date/time announced in class.
    1. provide a formal citation for each paper ___/6 (use the correct format to get full credit!)
    2. climate period names ___/2
    3. climate period age ranges ___/2
          10 points total


HOLOCENE STUDY



Compare the paper by Bond et al. (2001) with the classic Blytt-Syrnander sequence. Compare the ages of the bond-cycle events with the ages of the Blytt-Syrnander zone boundaries.
    1. Which Bond events are the closest matches in time to the B-S boundaries?
    2. What is the inferred climate during the Bond events?
    3. How could the climate of the events cause, or be correlated with the Blytt-Syrnander zone boundaries?
Submit a 500 word answer by email to Owen Davis odavis@email.arizona.edu

      2 points per answer for each question above
      4 points for clarity and writing
    10 points total

Bond, G., Kromer, B., Beer, J., Muscheler, R., Evans, M.N., Showers, W., Hoffmann, S., Lotti-Bond, R., Hajdas, I. and Bonani, G. 2001. Persistent solar influence on North Atlantic climate during the Holocene. Science 294: 2130-2136. www.sciencemag.org


PLUVIAL HISTORY



Compare the late-Pleistocene lake-level record for Lake Estancia (Allen and Anderson, 2000) with the two general lake-level records for Mediterranean vs. Monsoonal climate regions.
    1. Why are the Mediterranean and Monsoonal diagrams smoother than the L. Estancia lake-level record?
    2. Of those two regions (Mediterranean and Monsoonal), which does the L. Estancia record resemble more closely?
    3. Is the modern climate of Albuquerque (near L. Estancia) Mediterranean and Monsoonal?
Submit a 500 word answer by email to Owen Davis odavis@email.arizona.edu

    2 points per answer for each question above
    4 points for clarity and writing
  10 points total

Allen, B.D., and Anderson, R.Y., 2000. A continuous, high-resolution record of late Pleistocene climate variability from the Estancia basin, New Mexico. Geological Society of America Bulletin 112: 1444-1458. Viewed online at http://epswww.unm.edu/facstaff/gmeyer/eps481/LakeEstancia.pdf July 4, 2004.


PLEISTOCENE FLOODS




Compare and contrast the Spokane (Missoula, Channeled Scabland) OR the Bonneville flood with the Altai floods.
    1. What are the ages of the two floods?
    2. What were the apprixomate flood volumes and durations of the two floods?
    3. What were the water bodies for the floods (what formed the lake basins)?
    4. Where (across a valley?) and made of what (a delta?) were the dams?
Submit a 500 word answer by email to Owen Davis odavis@email.arizona.edu

    2 points per answer for each question above
    2 points for clarity and writing
  10 points total
Resources

QUATERNARY FAUNAS


Pleistocene Extinctions

Getting a conviction in the case of the Overkill Who-Dunnit (Homo, the serial killer). You'll need to demonstrate
  • motive and capability
  • opportunity (placing the perpetrator at the scene at the right time
Read Alroy's (2001) paper on overkill simulation and Miller et al.'s (1999) paper on mihirung extinction, and answer the following questions.
  1. Could humans have caused the megafaunal extinctions? (3 points)
    • is the population of human hunters necessary to cause megafaunal extinction reasonable?
    • would the duration and rate of hunting necessary to cause extinction be reasonable?
  2. Were humans on the scene at the time of the two extinctions? (3 points)
  3. Other cases: Name another case that seems to fit this pattern. (2 points)
  4. spelling, punctuation, neatness, clarity, and brevity (2 points)

Calibration and Transfer Functions

Use a statistical package, MS Excel, or (linear estimates) (see class notes) to calculate transfer functions for the following data from Adam's (1967) study of the contemporary pollen rain of the Sierra Nevada. Make the following calculations and comments, and send them as an email to me at odavis@email.arizona.edu .
    (1) Compute the transfer functions between oak pollen percentages and (a) mean annual precipitation and (b) average annual temperature, using the data in the table below.
    (2) Use the transfer functions to calculate the implied temperature and precipitation implied by a value of 25% oak pollen in a lake core from the western Sierra Nevada.
    (3) Do the same thing for a value of 50% oak pollen and compare the validity of the two (25% vs. 50%) calculations.
    (4) Comment on the correlation between the oak pollen percentages and the climate parameters. Is the fit good? Are the temperature and precipitation values you have calculated reliable?
Elev m Precip mm Temp oC Oak%
366 511 16 32.5
305 486 16 6
610 608 15 16.5
915 730 13 9
915 730 13 13
915 730 13 14.5
1220 852 12 23.5
1524 974 10 17
1829 1096 9 3
2134 1218 7 4
2485 1358 5 5
2317 1291 6 8
2439 1340 6 4
2744 1462 4 5
3034 1578 3 3.5
2744 832 4 8
2439 806 6 1.5
2104 777 8 3.5
2134 779 8 0
2484 810 6 5.5
2134 779 8 2

Adam, D.P. 1967. Late Pleistocene and Recent palynology in the central Sierra Nevada, California. In: Cushing, E.J., and Wright, H.E., Jr. (eds.) Quaternary Paleoecology. Yale Univ. Press, New Haven, Conn. p. 275-301.


NON MARINE LONG RECORDS


Oxygen Isotope Chronology

Locate two figures, from two different publications, showing single-variable curves for the terrestrial environment spanning the last 160,000 years and compare them to the marine oxygen isotope chronology. Use primary references, DO NOT use a figure from a paper that has already compiled data from different sources. Xerox the curves to the appropriate size and paste both on a piece of paper to facilitate comparison. The depth or time axis must be showing for each curve. For each curve, label isotope stages 1 - 6. Provide full, formal citations for each curve (see homework exercise one), on a separate piece of paper. Work independently, do not share resources.
    (1) provide a formal citations for the papers ___
    (2) two figures ___
    (3) label isotope stages 1 - 6 for each curve ___
    (4) spelling, punctuation, neatness, clarity, and brevity ___

ANNUAL DATES




Establishing the age of fossil records with annual precision, or greater, has become one of the goals of paleoclimatology in the new millennium. Scientists in various disciplins hope to reconstruct precise records of rapid, high-amplitude climatic changes.
Locate two scientific articles (NOT summaries or class materials), summarizing two different annual-resolution techniques. These include varves, tree rings, corals, and ice cores, but there are other less-developed techniques.
    (1) provide a formal citations for each article ___
    (2) provide a pragraph description for each OR two figures ___
    (3) spelling, punctuation, neatness, clarity, and brevity ___
    Send these in an email to me at odavis@email.arizona.edu attach copies of the figures, if you can.



DENDROCHRONOLOGY

Calibration and Verification




Many disciplines of Quaternary Ecology use calibration to determine the relationship between "proxy" fossil data and instrumental records (for example, temperature or precipitation). Fewer disciplines formally evaluate this relationship by checking the predictions produced by transfer functions against other time periods of the same time series. For the five data sets (pairs),
  1. calculate transfer functions and past temperatures (see example), and
  2. compare the calculated temperatures with the "verification" temperatures, do the calculated values over-estimate these values, under-estimate them, or verify them?

    Copy the table, past it into your word-processor, fill it out (four blanks to fill in for each of five rows), copy the completed table into an email to odavis@email.arizona.edu



RADIOMETRIC DATING

Radiometric Date Calibration



Use both calibration programs linked-to below to find the equivalent range of calendar ages for two radiocarbon dates.
  • Calibrate these two dates
    • 245 ± 55
    • 1980 ± 45
  • Copy, in the email, the range of calendar dates for each program, for both dates.
    Indicate which program gave which dates. Then, compare the different program's
    • ease of use
    • features
    • usefullness of results
  • send to odavis@email.arizona.edu
LINKS to Calibration Programs
  • Calib 5.0.2 online
  • CalPal online


  • Chronologic techniques



    List how the following processes are "set to zero" at the age of the object (substance) being dated.



    HOMEWORK EXERCISE:

    Chronologic techniques

    A fundamental similarity among the methods for dating Quaternary (and older) deposits is that geological and biological processes are calibrated to determine the rate at which some product accumulates (or disappears), so that a deposit or item can be dated depending on how much of that product has accumulated (or disappeared).
      Age = amount/rate
    These geological and biological rates may or may not be linear. For sake of simplicity, we will assume linear rates for problems 1 - 3 -- described by just two points. Review homework exercise 4 if you don't remember how to calibrate using two points. For questions 4 & 5, use the pre-determined exponential rates.

    Copy the five problems below to your computer, fill in the blanks for each question, cut and paste the completed exercise into an email to me.

    Each problem 2 points     __ / 10


    Problem 1: weathering of boulders: The depth of the weathering "rhind" on exposed bolders in a glacial moraine is realated to its age. Two moraines are of known age, the third is undated.
    age weathering layer thickness
    Moraine 1 200 Ka 5 mm
    Moraine 2 2 Ma 5 cm
    The rate is ___ mm / Ka.
    A boulder on the undated moraine has a weathering layer 8 mm thick.
    It is __ years old.


    Problem 2: soil formation. As soils weather, clays accumulate in the B horizon. Calculate the age of the undated soils based on the amounts of clay in the two dated soils. Fresh, unweatherd soils have 1-5 % clay.
    age percent clay in B horizon
    Soil 1 3 Ka 10 %
    Soil 2 9 Ka 40 %
    The rate is ___ % / Ka increase in clay content.
    The soil to be dated has 35% clay in the B horizon it is __ years old


    Problem 3: fission tracks are produced in crystals by natural fission of U238.

    Fourty nine (49) fissions tracks are counted on an etched, 1 mm2 surface of a crystal. After annealing and neutron irradiation, the natural average (linearized) accumulation of fission tracks on the crystal is calculated as 0.0014286 tracks cm-2 My-1. (The rate is not actually linear, but for this question, treat it as linear!)

    How old is the crystal? _____


    Problem 4: fresh exposures of glass, including obsidian, weather at an exponential rate.

    The rate of weathering of obsidian can be calibrated with samples of known age for a given locality and type of sample. For The Bull Lake area of Wyoming, the equation is

    AGE (Ka) = (36 x ln (thickness µm) ) - 14

    For the following rind thicknesses on three moraines, calculate the sample ages.
    Thickness (µm) AGE (Ka)
    45 _____
    12 _____
    2.5 _____


    Problem 5: carbon 14 decays to nitrogen at an exponential rate. See your notes for the appropriate equation for radiocarbon dating.
    For the following Actsample, (decays min-1 g-1 carbon) calculate the radiocarbon ages for these two-gram samples (organic matter dry weight), ignoring δ 13C ‰ fractionation and other factors.
    Actsample AGE (yr)
    10 _____
    5 _____
    2 _____



    PALEOMAGNETIC CHRONOLOGY



    Read the following article published in Geophysical Journal International. Send a 500-word critique of this paper to Owen Davis. odavis@email.arizona.edu
      (1) What elements of the Earth's magnetic are studied (define each) __/3
      (2) To which other paleomagnetic records is the L. Biwa one compared __/3
      (3) What are the authors' conclusions regarding Japan's PSV record __/3
      (4) spelling, punctuation, neatness, clarity, and brevity __/1


    LICHENOMETRY


    Lichenometry

    Answer the following questions assuming that the boundary between rapid (Great) growth and mature growth is 200 years.

    Question One.
      age lichen diameter
    Lichen 1 100 yr 8 cm
    Lichen 2 200 yr 15 cm
    Lichen 3 800 yr 35 cm


    The lichen to be dated has a diameter of 3 cm it is __ years old.

    The lichen to be dated has a diameter of 12 cm it is __ years old.

    The lichen to be dated has a diameter of 20 cm it is __ years old.

    The lichen to be dated has a diameter of 30 cm it is __ years old.

    The lichen to be dated has a diameter of 50 cm it is __ years old.


    Question Two.
      age lichen diameter
    Lichen 1 100 yr 5 cm
    Lichen 2 200 yr 10 cm
    Lichen 3 800 yr 25 cm


    The lichen to be dated has a diameter of 3 cm it is __ years old.

    The lichen to be dated has a diameter of 12 cm it is __ years old.

    The lichen to be dated has a diameter of 20 cm it is __ years old.

    The lichen to be dated has a diameter of 30 cm it is __ years old.

    The lichen to be dated has a diameter of 50 cm it is __ years old.

    ROCK VARNISH


    C3 - C4 plants

    Summarize a recent (last 15 years) paper using C3 - C4 differences among plants to reconstruct Quaternary environments. Hand in a one page summary clearly indicating the environmental parameter studied: climate, atmospheric CO2, diet . . . .

    How was the C3 / C4 photosynthetic pathway of plants determined ( δ 13C , fossils . . .)?

    For what period of the Quaternary was the environment reconstructed?

    How was that Quaternary environment different from that of today (be specific, ppmv CO2, oC, mm precipitation . . .)

    Include a formal citation for the paper summarized, using the format outlined in the first homework exercise. Work independently, do not share resources.

    VOLCANIC TEPHRA



    - NONE -

    HISTORY



    - NONE -

    HISTORY



    - NONE -

    PALEOCLIMATE




    Semipermanent Features and ACRONYM weather patterns

    Use the internet (see links at bottom of class home page) to find a recent paper on Quaternary climate change that uses (one each) as an explanatory tool. For example, shifts in the strength or position of the ITCZ or of ENSO events.

    1. provide a formal citation for the paper ___ /2
      Be sure to follow the citation format used in this class in the REFERENCES +
    2. mention the kind(s) of "proxy data" (treerings, pollen ...) used ___ /2
    3. list which Semipermanent Feature(s) & acronym pattern(s) are used ___ /2
    4. append one appropriate figure or table showing the feature and it's change ___ /2
        (this is an internet exercise, you should be able to copy a figure or table and paste it directly into the homework)
    5. spelling, punctuation, neatness, clarity, and brevity ___ /2
    You should email this homework assignment to odavis@email.arizona.edu. If possible, you should include your homework in the body of the message - not as an attachment.

    GEOLOGICAL CAUSES OF CLIMATE CHANGE


    Geological causes of climate change.

    Summarize one recent (last 15 years) paper on Quaternary climate change that uses Geological or Geophysical Changes as causes of climatic change. These causes include
    • changes in global paleogeography
    • changes in sea-floor spreading rates, and
    • tectonism (mountain building).

    1. provide a formal citation for the paper ___

    2. mention the kind(s) of geological change ___

    3. discuss the climatic effect (amplitude and sign) of the changes ___

    4. was the effect local, regional, or global? ___

    5. spelling, punctuation, neatness, clarity, and brevity ___

      Email this homework assignment to odavis@email.arizona.edu. Include your homework in the body of the message - not as an attachment.


    SOLAR






    The historic warming has been attributed to various forcing functions. Read Crowley's [link] and Jukes et al.'s link papers.
        __ /10

    1. What was the source of temperature data for the last 1000 years? in Crowley's vs. Jukes et al.'s papers (what proxy data were combined to make the two records ?) __/2

    2. What climate forcing factors were evaluated in Crowley's paper? __/2

    3. What are Crowley's conclusions, and what predictions does he make? __/4

    4. According to Jukes et al.'s paper, how much warmer have the two warmest years, recently what years are they, and how much warmer (oC) were they than the overall average? __ /2


      Email this homework assignment to odavis@email.arizona.edu.
      Attached files or paper copies will not be graded.



    SOLAR 2


    Solar variability as a cause of climate change.

    Summarize one recent (last 10 years) paper on Quaternary climate change that uses Solar Variability as a primary cause of climatic change.
    1. provide a formal citation for the paper ___

    2. mention the proxy records used to (a)record past solar variability and (b) record the climate effects ___

    3. attach one figure showing the history of solar variability or climate change ___

    4. discuss the climatic effect (amplitude and sign [colder or warmer]) of the solar variability ___

    5. spelling, punctuation, neatness, clarity, and brevity ___

      Email this homework assignment to odavis@email.arizona.edu. Include your homework in the body of the message - not as an attachment.


    ASTRONOMICAL


    Feedbacks and the astronomical theory of climate change

    Summarize one recent (last 15 years) paper on the environmental feedbacks that amplify the timing signal produced by changes in the Earth's orbit (the astronomical theory of climate change). These feedback mechanisms include (among many others)

    • albedo (reflectance of solar energy: snow, vegetation, sea ice)
    • atmospheric circulation (effect of continental glaciers)
    • isostatic depression (glacier thinning)
    • ocean circulation (thermohaline circulation, land bridges)
    • sea surface temperature (aridity and glacier thinning)
    • sea surface lowering (exposure of continental shelf)

    1. provide a formal citation for the paper ___

    2. mention the environmental feedback(s) investigated ___

    3. mention the proxy record used to record the environmental feedback(s) ___

    4. discuss the climatic effect (amplitude and sign) of the feedbacks ___

    5. spelling, punctuation, neatness, clarity, and brevity ___

      (6) This assignment must be emailed to odavis@email.arizona.edu. Include your homework in the body of the message - not as an attachment.


    ATMOSPHERIC


    Greenhouse gasses and climate change

    Read Crowley's paper on modeling climate change over the last 1000 years. http://www.sciencemag.org/cgi/content/full/289/5477/270 or [ref] (p. 13)
    1. Which three proxies for climate change were used? ___/3

    2. Which three causes of climate change were compared? ___/3

    3. Of the three causes, which two best explain climate variability before 1900? ___/2

    4. Of the three causes, which one best explains climate change after 1950? ___/2

      Email this homework assignment to odavis@email.arizona.edu.


    ATMOSPHERIC TOO



    WAS THE CLIMATE OF THE LATE CRETACEOUS AND EOCENE REALLY THAT DIFFERENT FROM THE HOLOCENE?

    A 2001 paper in SCIENCE presents isotopic evidence that the tropical sea surface temperature of the late Cretaceous was 10-15 oC what had been estimated from previous isotopic analysis.

    (1) What "breakthrough" is responsible for the higher SST estimates? ___

    (2) How do the (new, improved) SST estimates compare with modern SST's? ___

    (3) Summarize one paper citing fossil evidence (e.g., one of the 4 non-Pearson papers, below) from a polar region that indicates warm Cretaceous - Eocene climate ___

    (4) provide a formal citation for the "fossil paper" ___

    (5) spelling, punctuation, neatness, clarity, and brevity ___

    (6) Email this homework assignment to odavis@email.arizona.edu. Include your homework in the body of the message - not as an attachment.

    Pearson, P.N., Ditchfield, P.W., Singano, J., Harcourt-Brown, K.G., Nicholas, C.J., Olsson, R.K., Shackleton, N.J. and Hall, M.A. 2001. Warm tropical sea surface temperatures in the Late Cretaceous and Eocene epochs. Nature 413: 481-487.

    Basinger, J.F., Greenwood, D.R., and Sweda T. 1994. Early Tertiary vegetation of Arctic Canada and its relevance to paleoclimatic interpretation. p. 175-198 in: Boulter M.C. and Fisher H.C. (eds.) Cenozoic plants and climates of the Arctic. Springer-Verlag.

    Frederiksen, N.O., Ager, T.A., and Edwards, L.E. 1988. Palynology of Maastricchtian and Paleocene rocks, lower Colville River region, North Slope of Alaska. Canadian Journal Earth Sciences 25: 512-527.

    Markwick, P. 1998. Fossil crocodilians as indicators of Late Cretaceous and Cenozoic climates: implications for using paleontological data in reconstructing paleoclimate. Palaeogeography, Palaeoclimatology, Palaeoecology 137: 207-271.

    Spicer, R.A. and Parrish, J.T. 1990. Late Cretaceous - early Tertiary palaeoclimates of northern high latitudes: a quantitative review. Journal Geological Society London 147: 329-341.


    ATMOSPHERIC


    Greenhouse gasses and climate change

    Summarize one recent (last 15 years) paper on the effects of greenhouse Gasses (CO2, CH3, ...) on global climate change. The paper should treat one or more of the following timescales (aspects) of atmospheric causes of climate change
    • evolution of the earths atmosphere over the last 4 billion years

    • Phanerozoic (last 700 Ma) evolution of the atmosphere and ice ages

    • rates of sea floor spreading and atmospheric CO2,

    • lowering of greenhouse gasses leading to the Pleistocene ice age

    • fluctuations of atmospheric greenhouse gasses on glacial / interglacial timescales

    • late Holocene (including historic) changes in atmospheric greenhouse gasses

    (1) provide a formal citation for the paper ___

    (2) mention the climate proxy used to record past climate ___

    (3) mention the proxy record of past greenhouse gas concentration ___

    (4) discuss the climatic effect (amplitude and sign) of the greenhouse gas ___

    (5) spelling, punctuation, neatness, clarity, and brevity ___

    (6) Email this homework assignment to odavis@email.arizona.edu. Include your homework in the body of the message - not as an attachment.

    Volcanic eruptions and climate change


    Volcanic eruptions and climate change

    Summarize one recent (last 15 years) paper on the climatic effects of a major volcanic eruption.

    (1) provide a formal citation for the paper ___

    (2) mention the geographical location (and past eruptive history) of the volcano ___

    (3) mention the volume and composition of aerosols produced by the eruption ___

    (4) discuss the climatic effect (amplitude and sign) of the eruption ___

    (5) spelling, punctuation, neatness, clarity, and brevity ___

    (6) Email this homework assignment to odavis@email.arizona.edu. Include your homework in the body of the message - not as an attachment.

    SEDIMENTS


    Aquatic sediments as recorders of environmental change

    Summarize one recent (last 15 years) paper relying on aquatic (lake, bog, river [not ocean]) sediments as a source of proxy data for climate change. The Journal of Paleolimnology would be an excellent place to find such a paper. You may ask Professor Andrew Cohen for access to this journal, because the UofAz Libraries do not have a copy.

    (1) provide a formal citation for the paper ___

    (2) mention the proxy data (pollen, isotopes, geochemistry . . .) used ___

    (3) mention the environmental parameters (air temperature, etc.) reconstructed ___

    (4) discuss the proposed causes of the environmental changes ___

    (5) spelling, punctuation, neatness, clarity, and brevity ___
    (6) Email this homework assignment to odavis@email.arizona.edu. Include your homework in the body of the message - not as an attachment.

    CAVES


    Cave sediments as recorders of environmental change

    Summarize Grayson and Madsen's (2000, [ref] [cls]) paper on Homestead Cave. Specifically mention

    1. Location, environment/climate and dating of sediments __/6
    2. What is "Brown's Hypothesis" and what evidence from Homestead Cave supports or refutes it __/2
    3. spelling, punctuation, neatness, clarity, and conciseness __/1
    4. provide a formal citation for the paper in the correct format __/1
    Email this homework assignment to odavis@email.arizona.edu. Include your homework in the body of the message - not as an attachment.

    CAVES TOO


    Summarize the paper by Polyak and Asmerom (2001) and compare it with climatic reconstructions for the West in Davis (1994) and Stine (1994). Follow the instructions above (email it to me).

    Davis, O.K. 1994. The correlation of summer precipitation in the southwestern U.S.A. with isotopic records of solar activity during the Medieval warm period. Climate Change 26: 271-287.

    Polyak, V.J. and Asmerom, Y. 2001. Late Holocene climate and cultural changes in the southwestern United States Science. 294: 148-151.

    Stine, S. 1994. Extreme and persistent drought in California and Patagonia during medieval time. Nature 369: 546-549.



    PALYNOLOGY



    Pollen Concentration and Accumulation

    Calculate the pollen concentration and pollen accumulation rate (influx) for the two sites.

    SITE 1
    Dates: surface = 0 yr B.P., 2 m = 1000 yr B.C.
    Volume of each pollen sample = 5 cm3
    Tracers added to each pollen sample = 10,000 tracers
    SAMPLE
    DEPTH
    (cm)
    POLLEN
    SUM
    (grains)
    TRACERS
    COUNTED
    (tracers)
    POLLEN
    CONCENTRATION
    (grains/cm3)
    POLLEN
    INFLUX
    (grains/cm2/yr)
    5 300 150 __________ __________
    10 300 300 __________ __________
    100 300 450 __________ __________


    SITE 2
    Dates: surface = 0 yr B.P., 7 m = 5000 yr B.P.
    Tracers added to each pollen sample = 12,000
    Volume of each pollen sample = 1 cm3
    SAMPLE
    DEPTH
    (cm)
    POLLEN
    SUM
    (grains)
    TRACERS
    COUNTED
    (tracers)
    POLLEN
    CONCENTRATION
    (grains/cm3)
    POLLEN
    INFLUX
    (grains/cm2/yr)
    5 200 200 __________ __________
    100 400 200 __________ __________
    500 600 200 __________ __________


    SITE 3
    Dates: surface = 0 yr B.P., 2 m = 2000 yr B.P.
    Volume of each pollen sample = 5 cm3
    Tracers added to each pollen sample = 10,000 tracers
    SAMPLE
    DEPTH
    (cm)
    POLLEN
    SUM
    (grains)
    TRACERS
    COUNTED
    (tracers)
    POLLEN
    CONCENTRATION
    (grains/cm3)
    POLLEN
    INFLUX
    (grains/cm2/yr)
    10 300 300 __________ __________
    20 500 500 __________ __________
    30 1000 1000 __________ __________


    SITE 4
    Dates: surface = 0 yr B.P., 2 m = 10,000 yr B.P.
    Volume of each pollen sample = 5 cm3
    Tracers added to each pollen sample = 10,000 tracers
    SAMPLE
    DEPTH
    (cm)
    POLLEN
    SUM
    (grains)
    TRACERS
    COUNTED
    (tracers)
    POLLEN
    CONCENTRATION
    (grains/cm3)
    POLLEN
    INFLUX
    (grains/cm2/yr)
    0 300 450 __________ __________
    10 300 900 __________ __________
    20 300 150 __________ __________


    Cut and paste this exercise into a text editor, fill in the blanks, then either (1) cut and paste the completed exercise into an email document and send to odavis@email.arizona.edu (2) hand in the completed exercise on paper at the beginning of class


    MACROFOSSILS



    Taphonomy of Plant Macrofossils



    Birks' work (assigned reading) systematically addresses the taphonomy of plant macrofossils (the "D" and "R" of "f[PDRI]"). (see taphonomy definitions 1 & 2!)

    According to Birks (pp 12-14):

    (1) What is one way by which "Dispersal" removes macrofossils of aquatic and terrestrial plants from the fossil record? ___/2pts

    (2) What are three ways in which the lack of "Preservation" removes macrofossils of aquatic and terrestrial plants from the fossil record? ___ /6pts

    (3) spelling, punctuation, neatness, following instructions ___/2pts


    Email this homework assignment to odavis@email.arizona.edu. Include your homework in the body of the message - not as an attachment. For full credit, the subject line must contain, "GEOS 462 HOMEWORK 11."


    MACROFOSSILS too


    Disagreement among fossil indicators

    Summarize one recent (last 10 years) that includes two conflicting kinds of proxy data (e.g., pollen vs. plant macrofossils) to produce a reconstruction of Quaternary environments.

    (1) provide a formal citation for the paper format ___

    (2) mention the kinds of proxy data (pollen, isotopes, geochemistry . . .) used ___

    (3) mention the environmental parameters (temperature, precipitation) reconstructed ___

    (4) discuss the conflict and its resolution (or lack thereof) ___

    (5) spelling, punctuation, neatness, clarity, and brevity ___


    Email this homework assignment to odavis@email.arizona.edu. Include your homework in the body of the message - not as an attachment.

    PACKRATS


    "Middens"

    New & interesting research in packrat-midden science.
    1. "Packrat middens" on the web. "Google it" and look up "packrat middens" in Wickipedia.
        __/2 pt. Provide a URL for a packrat midden web page
        __/2 pt. How complete and accurate is the page (compare to readings and lecture notes and other knowledge you may have)

    2. Recent "packrat midden" literature
      Use the UA "electronic journal" search to find TWO recent (2006 or 2007) "packrat midden" articles in two leading "Quaternary" journals.
      • The Holocene
      • Palaeogeography, Palaeoclimatology, Palaeoecology
      • Quaternary International
      • Quaternary Research
      • Quaternary Science Reviews
      BE CAREFUL! Don't cite shell-midden or human trash-middens articles, (hyrax & stick-rat are OK)

      For each article provide a formal citation using the "Geos 462" format
        __/3 pt. article one
        __/3 pt. article two

        DO NOT JUST COPY AND PASTE THE REFERENCE FROM THE SCREEN
        (= no credit)

        ___/10
    Email this homework assignment to odavis@email.arizona.edu. Include your homework in the body of the message - not as an attachment.

    CHARCOAL


    History of Fire Frequency

    Compare and contrast the papers of Millspaugh et al. (2000) and Pierce et al. (2004) in the references (See References).

    1. For each study, what proxy data are used to indicated past fire frequency or intensity (e.g., fire scars, sedimentary charcoal)? ___ (2 pts)

    2. How is each proxy record dated (e.g., tree rings, 210Pb, 14C)? ___ (2 pts)

    3. When (name the year and climatic interval) was fire-frequency greatest, and how extreme was it (e.g., fires/year, area burned, times-modern . . .) ___ (3 pts)

    4. Are the peak frequencies synchronous for the two studies? Why or why not (e.g., climate vs. human-caused)? ___ (3 pts)
    Email this homework assignment to odavis@email.arizona.edu. Include your homework in the body of the message - not as an attachment.
    To receive credit, the subject line must read, "GEOS 462 HOMEWORK 12."

    CHARCOAL 2


    Sedimentary Charcoal

    Answer the following questions based on the assigned reading (Patterson et al., 1987)

    (1) About what percentage of burned wood becomes charcoal? 2 points

    (2) What are the two primary routes by which charcoal is transported to a lake/bog basin? 2 points

    (3) What are three methods by which charcoal abundance in sediment is quantified? ___ 6 pionts

    Email this homework assignment to odavis@email.arizona.edu. Include your homework in the body of the message - not as an attachment.


    PHYTOLITHS


    Phytoliths and plant cuticles as recorders of environmental change

    Summarize the Bremond et al. paper on phytoliths from Mediterranean vegetation.

      Methods:

    1. What was the purpose of the investigation? __2pt

    2. How many samples were analyzed for phytoliths, and what size of sample? __2pt

      Results:

    3. What effect did soils have on phytolith abundance (e.g., calcareous substrates vs. other)? __2pt

    4. What is the relationship between the abundance of grass-type phytoliths in the samples and grass plant abundance where the samples were taken? __2pt

    5. What is the relationship between phytolith types and the abundance of pines and oaks where the samples were taken? __2pt

    Email this homework assignment to odavis@email.arizona.edu. Include your homework in the body of the message - not as an attachment.

    INVERTEBRATES


    Arctic Beetles

    Summarize Scott Elias' 2000 paper [ref]
    1. How many sites were studied, where were they geographically, and what were their ages (six categories)? __ 4pts

    2. How many species were recovered? __ 1pt

    3. What are "TMAX" and "TMIN" and what are the average values of those variables for the species recovered? __ 3pts

    4. What has been the pattern of species diversity in glacial vs. interglacial periods? __ 2pts
    Email this homework assignment to odavis@email.arizona.edu. Include your homework in the body of the message - not as an attachment.

    INVERTEBRATES 2


    No-analog associations

    Summarize one recent (last 15 years) paper that finds disagreement among two indicator fossils (plant fossil vs. plant fossil, plant fossil vs. beetle fossil . . .)

    (1) provide a formal citation for the paper (format) ___

    (2) mention the types (e.g., phytoliths vs. macrofossils) of conflicting fossils ___

    (3) mention the environmental parameters (vegetation, climate) reconstructed ___

    (4) how is the "conflict" resolved? If not, why not ___

    (5) spelling, punctuation, neatness, clarity, and brevity ___

    Email this homework assignment to odavis@email.arizona.edu. Include your homework in the body of the message - not as an attachment.

    SOILS


    Fossil soils

    Summarize one recent (last 15 years) paper that uses fossil soils to reconstruct Quaternary environments.

    (1) provide a formal citation for the paper (format) ___

    (2) mention the types soil data used (color, texture . . .) ___

    (3) mention age and type (soil order) of the soil ___

    (4) discuss the environmental parameters (vegetation, climate) reconstructed ___

    (5) spelling, punctuation, neatness, clarity, and brevity ___


    Email this homework assignment to odavis@email.arizona.edu. Include your homework in the body of the message - not as an attachment.

    HISTORICAL RECORDS


    Historical documents

    Read the reconstruction of climate in China by (Ge et al., 2007)

    (1) list the proxy (historical records of what?) converted to environ. estimates ___/2

    (2) what environmental (climatic) parameter was reconstructed in the Ge et al. paper? ___/2

    (3) compare the the Ge et al. paper (figs. 5, 6) with (Mann et al.'s, 1998) (fig. 5) and (Crowley's, 2000) (fig. 1) reconstructions of global climate
      Comment on the (presence/absence) relative amplitudes of

    • Historical warming         Ge et al.____ Mann et al.____ Crowley____ ___/2
    • Little Ice Age                   Ge et al.____ Mann et al.____ Crowley____ ___/2
    • Medieval Warm Period Ge et al.____ Mann et al.____ Crowley____ ___/2

    ___ / 10 pts      

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    ARCHEOLOGY


    Modeling Archeological Populations

    Read the following article and answer the questions.

    Axtell, R.L., Epstein, J.M., Dean, J.S., Gumerman, G.J., Swedlund, A.C., Harburger, J., Cakravarty, S., Hammond, R., Parker, J., and Parker, M. 2002. Population growth and collapse in a multiagent model of the Kayenta Anasazi in Long House Valley. Proceedings of the National Academy of Science 99: 7275-7279.
    Available in the Science Library Q11 .N26
    or online www.pnas.org/ (UofAz computers or subscrption)

    (1) what population is modeled - where, who and when? ___ 2 pts

    (2) what environmental parameters were the basis for the model? ___ 2 pts

    (3) what proxy data were the basis for the climatic parameters? ___ 2 pts

    (4) what was the maximum population for the model, and when did it occur ___ 2 pts

    (5) spelling, punctuation, neatness, clarity, and brevity ___


    Email this homework assignment to odavis@email.arizona.edu. Include your homework in the body of the message - not as an attachment.

    PERIGLACIAL


    Glacial and periglacial indicators of climate change

    Summarize one recent (last 15 years) paper that focuses on glacial and periglacial indicators of climate change.

    (1) provide a formal citation for the paper (format) ___

    (2) mention the proxy data used to reconstruct glacial and periglacial features ___

    (3) mention the calibration process the features versus climate ___

    (4) discuss the timing and magnitude of the proposed climate change ___

    (5) spelling, punctuation, neatness, clarity, and brevity ___


    Email this homework assignment to odavis@email.arizona.edu. Include your homework in the body of the message - not as an attachment.

    BIOGEOGRAPHY


    Pleistocene biogeography



    On this map of North America (click on image, copy, paste) draw the full-glacial (oxygen isotope stage 2, ca. 18,000 radiocarbon years ago) limit or extent of the following features. Use the assigned reading for "Pleistocene Biogeography," the materials in our online notes and your textbook.


      Hydrosphere (3 pts)
        Coastal Geography, Pluvial Lakes, Proglacial Lakes
        (example: sea-level was 125 m lower, so Gulf of California was smaller)
      Cryosphere (3 pts)
        Continental Glaciers, Montane Glaciers
      Biosphere (3 pts)
        Tundra, Conifer Forest, Broadleaf Forest, Woodland, Steppe, Desert

      Colored pencils help!
    (1 pt)
    Hand in paper copy, at the beginning of class - or -
    Email this homework assignment to
    odavis@email.arizona.edu. Include your homework in the body of the message - not as an attachment.
    To receive credit, the subject line must read, "GEOS 462 HOMEWORK 12."