Department of Earth Sciences
GEO/CHE 475 -- Solid Earth Geochemistry
Fall, 2007  

instructor, office: Dr. Paul Tomascak, Piez 207a
phone: 315.312.2786; email: tomascak@oswego.edu
lectures & labs: Piez rm.207
textbook: online textbook by W. White, Cornell Univ. http://www.geo.cornell.edu/geology/classes/geo455/Chapters.HTML
Click here for a pdf version of the course syllabus and schedule.

DATES OF INTEREST:

 Friday 9/7 - selection of topic due via email by 5:00 p.m.
Monday 9/17 - class discussion on the early Earth and Earth-Moon system begins
Wednesday 9/19 - preliminary list references due (at least 10) in class
Remember: although first drafts are not due until early November, I am happy to read over partial text to give feedback.
First drafts of research papers are due on 11/2/07.
In lab 10/25/07 we will make dilutions of our samples and standard solutions for the AA, then go make some measurements.
In lab 11/1/07 we will meet at the AAS lab (Snygg 224). You must have safety eyewear for these exercises.
Final drafts of research papers are due on 11/26/07. This time, late papers will not be accepted. Remember to use GCA format (see link below).
Lab on 11/29/07 will begin at 10:00. If you are available, please plan to attend the talk at 9:00 in Piez 228.
Lecture deviation: Due to incoming candidates for the faculty position in paleontology/stratigraphy, on Monday 12/3 students will attend the research lecture, after which we will have our regular (abbreviated) geochemistry lecture. The lecture begins at 2:30, so please arrive on time unless your previous course meets then. Location will be posted.

HANDOUTS:

 Click here for a pdf version of the Lab #1 handout (29 kB).
Click here to download the Excel sheet for Lab #1.
Click here for a pdf version of the Lab #2 handout (29 kB).
Click here for a pdf version of the Lab #3 handout (24 kB).
Click here for a pdf version of the warning on safe use of HF (37 kB).
Click here for a pdf version of the Lab #4 handout (37 kB).
Click here for a pdf version of the Lab #5 handout (35 kB).
Click here for a pdf version of the Lab #7 handout (34 kB).

References Used in Handouts and Assignments:
1. Faure G (1991) Principles & Applications of Inorganic Geochemistry. Macmillan [ISBN 0-02-336441-6]
2, 4, 5, 6. Davis AM (ed.) (2005) Treatise on Geochemistry, vol.1, Meteorites, Comets and Planets. Elsevier-Pergamon [ISBN 0-08-044720-1]
3. Beatty JK, O'Leary B, Chaikin A (Eds) (1981) The New Solar System. Sky Publishing [ISBN 0-933346-26-3]
statistics reference: Skoog, Holler & Nieman (1998) Principles of Instrumental Analysis. Thomson Learning [ISBN 0-003-002078-6]
7, 10. Karato S-I (2003) Dynamic Structure of the Deep Earth. Princeton Univ. Press [ISBN 0-691-09511-6]
8, 12. Carlson RW (ed.) (2005) Treatise on Geochemistry, vol.2, The Mantle and Core. Elsevier-Pergamon [ISBN 0-08-044848-8]
9. {available on shelves @ Penfield} Kellogg LH, Hager BH, van der Hilst R (1999) Compositional stratification in the deep mantle. Science 283, 1881-1884.
11. Jordan TH (1988) Structure and formation of the continental tectosphere. J Petrol Special Lithosphere Issue, 11-37.
13. Dalrymple GB (2001) in The Age of the Earth: from 4004 BC to AD 2002. Geol Soc Spec Pub 190 [ISBN 0-86239-093-2]
14. Sun SS (1985) Nature 316, 103-104. {available on shelves @ Penfield}
15. Weaver BL (1991) Earth Planet Sci Lett 104, 381-397. {electronic copy available from me}
16. White WM (1985) Geology 13, 115-118. {available on shelves @ Penfield}
17. Hoffman AW & White WM (1982) Earth Planet Sci Lett 57, 421-436. {electronic copy available from me}
18. Tera F et al. (1986) Geochim Cosmochim Acta 50, 535-550. {available on shelves @ Penfield}
19. Morris JD & Hart SR (1983) Geochim Cosmochim Acta 47, 2015-2030. {available on shelves @ Penfield}
20. Ellam RM & Hawkeswoth CJ (1988) Contrib Mineral Petrol 98, 72-80. {electronic copy available from me}
21. Zindler A & Hart SR (1986) Ann Rev Earth Planet Sci 14, 493-571. {paper copy available from me}
22. Langmuir CH, Vocke RD Jr, Hanson GN (1978) Earth Planet Sci Lett 37, 380-392. {paper copy available from me}
23. Chauvel C, Dupre B, Jenner GA (1985) Earth Planet Sci Lett 74, 315-324. {electronic copy available from me}
ASSIGNMENTS:

* (HW#1) For class on Monday 9/10/07, use a spread sheet program to create a plot of solar system (i.e., the Sun) abundance of the elements up to U. On the ordinate plot log abundance, on the abcissa plot atomic number (Z).
Locate data at http://www.earthref.org [click on "GERM" and go from "RESERVOIR DATABASE" to "Search for Reservoirs"; you may have to scroll almost to the bottom to locate the "Solar Photosphere" data set]
From this list choose the values from Palme & Jones (2004)--note concentrations are log units, relative to H=12.
Be prepared to discuss the data and to hand in your one page graph.
Additionally, provide responses for the following questions:
1. Why are H, He so much more abundant than everything else?; 2. Why does abundance decrease as Z increases?; 3. Why are some elements anomalously abundant/impoverished?; 4. Why are even Z elements more abundant than adjacent odd Z elements?

* For class on Monday 9/17/07, I will be choosing students at random to lead discussions on the two recent Meteoritics abstracts (click here for pdf; 49 kB). You may need to do some background work on the content for these, although the recent handouts should help.

* (HW#2) For class on Wednesday 9/19/07, you will report on topics disseminated in Monday's class, relevant to the current state of knowledge of a variety of extraterrestrial bodies, phenomena and the like. A brief written summary is required.

* (HW#3) For class on Monday 10/1/07, write up the most important findings from references 9, 10 & 11 on mantle structure. You can click here for a summary of reference #9.

* For class on Wednesday 10/3/07, read Chapter 7 in White (sect. 7.1 & 7.2) and handout #12 (Wood and Blundy). Much of the material in White should be a review of things that either we have discussed in week 1 or that you know from previous courses. Take notes and be prepared to discuss the geological significance of the major trace element groups.

* (HW#4) For class on Monday 10/8/07: (1) Use Excel to make a chondrite normalized plot of the lanthanides. Find data from one rock sample in the literature (please cite your reference). All plots must conform to what we outlined in class and have a continuous line connecting all measured elements. To normalize, use the Nakamura (1974) values in Table 7.3 in White. (2) Compile data from the GERM web site to list the partitioning of the following elements between plagioclase and basaltic melt in order of decreasing D: Li, V, Nb, Zn, Pb, Rb, Sr. Justify any choices you need to make in the process. (3) Make a plot of ionic radius versus charge for elements to Z = 57. Use ionic radii for octahedral coordination, where possible. Use the Shannon (1976) data that are compiled in Appendix A of the Nesse Introduction to Mineralogy text.

* (HW#5) For class on Wednesday 10/10/07, turn in the homework problems linked here. (11 kB pdf)

* (HW#6) For class on Monday 10/15/07, turn in the homework problem linked here. (14 kB pdf)

* For class on Wednesday 10/17/07, students will lead discussion about the five primary pathways of nuclear decay. See White, Chapter 8, but I encourage getting more information from additional sources (e.g., Principles of Isotope Geology by G. Faure).

* (HW#7) For class on Monday 10/22/07, turn in a summary of reference #13 and be ready to talk about geochronology and the age of the Earth.

* Calculations for Lab #6 are due on Tuesday 10/23/07 (so I can get them back to you in time for lab). Click here for the directions (20 kB pdf).

* (HW#8) For class on Monday 10/29/07, turn in the homework problems linked here. (26 kB pdf)

* (HW#9) For class on Wednesday 10/31/07, find in the geochemical literature a publication with radiogenic isotope data specifically applied to geochronology and plot them (or some component of them) using Isoplot 3.0. Be prepared to turn in any plot you make in addition to a brief summary of what is plotted and its significance.

* (HW#10) For class on Monday 11/12/07, be prepared to lead discussion on your paper (Kauffman = 17, Stringer = 14, Smith = 19, Williams = 16, Grade = 20, Cunningham = 15, Teeter = 18), plus discuss ref #21 (I will lead). Have a written summary to hand in on this date.

* Your compte-rendu of the Syracuse University Lab Tour is due on Thursday 11/29/07. I expect a clear and detailed description of what we saw and the capabilities of the instrumentation.

* (HW#11) For class on Monday 12/3/07, turn in your calculations and written results for the mixing problem we began discussing before break. Click here for the required data and equations. The last homework of the semester!

* * * FINAL EXAM : EMAILED DATA FOR THE TAKE-HOME ON SUNDAY MORNING. IF YOU DID NOT RECEIVE THIS, IT IS URGENT THAT YOU CONTACT ME! * * *
SOLUTIONS & OTHER HELPFUL THINGS:

* Click here for the cosmic abundance chart, as I would draw it.
* Check this image out: Saturn's whoopie-pie moon Iapetus!
* Click here for Geochimica et Cosmochimica Acta guidelines for manuscript format.
* Click here for the Louise Kellogg interpretation of mantle structure.
* Click here for a brief overview of the USGS Reference Materials Program (how rock standards are made). (411 kB pdf file)
* Click here for a brief summary article on the rare earth elements. It is dated in many respects (e.g., analytical methods) but the parts on the nature of the elements, their occurrence in the Earth, and their uses are quite worthwhile and easy reading. (733 kB pdf file)
* Click here for the IUPAC-sponsored periodic table of the elements. (28 kB pdf file)
* Click here for isotopic compositions of the elements, 1997, from your friends at the IUPAC. (137 kB pdf file)
* Click here for concentrations of various AAS standard solutions. (xx kB pdf file) [Mg dilutions: "0.05ppm" = 0.053ppm; "0.1ppm" = 0.110ppm; "0.3ppm" = 0.318ppm; "0.5ppm" = 0.521ppm; "1.0ppm" = 0.778ppm; "3ppm" = 2.89ppm]
* The reference for mixing calculations by Langmuir et al. is #22 above.
* The paper I mentioned in class on the perils of geochronology by the isochron method ("The Sm-Nd age of the Kambalda volcanics is 500 Ma too old!") by Chauvel et al. is #23 above.
* Click here for a list of Sm and Nd nuclide masses, needed for the isotope dilution calculations (Lab #7).
* Click here for images from the SU Lab tour.
EXAM PREP:

As the semester goes along, here are some questions you might consider as you set your sights on the Final Exam:
* Describe the major forces that have affected the evolution of chemical compositions in the cosmos from the Big Bang to the assembly of our solar system, including how we know these details.
* What is the relationship between elemental abundances in the Sun and in carbonaceous chondrites (meteorites), and why is this so important?
* Relate the physical and chemical variations we see in meteorites to their origins.
* Discuss the prevalent models for the origin of the Earth's Moon, including the main points for and against each.
* What evidence do we have for the existence of elements like O, C, P, S, Si in the Earth's core? Which are more/less likely to be there in percent-abundance?
* What is it about the lanthanide elements that makes them so useful in so many geochemical applications?
* Be prepared to perform calculations, given appropriate formulas and related data, for batch melting and fractional crystallization of igneous systems, and to interpret data related to these models.
* Discuss the age of the Earth and the history of our understanding of this problem.
* Compare and contrast geochemical analysis by atomic absorption spectroscopy and mass spectrometry. What are the important applications of each?
* Explain the isochron approach to radiometric dating, including not only how it works and what is required for it to work properly, but ways in which it may not yield geologically meaningful results.
* Be prepared to describe and critique geochronometers applied to different materials of different age -- which is best suited for which purpose, etc.
* Perform calculations for radiogenic isotope tracer systems (epsilon Nd, depleted mantle model ages, etc.) and be able to interpret data sets for radiogenic tracers.
* Summarize the methods and perspectives gained on mantle heterogeneity through studies of elemental and isotopic compositions of oceanic basalts.
* Be able to apply the binary mixing equation to attack various geochemical problems, and to know when mixing is or is not a viable explanation for a given group of data.

Useful web sites for the course:

journal web sites:

The American Mineralogist
The Canadian Mineralogist
European Journal of Mineralogy
Geochimica et Cosmochimica Acta
Chemical Geology
Earth and Planetary Science Letters
Meteoritics and Planetary Science
Journal of Petrology

other resources:

Mineralogical Society of America
The Geochemical Society
The Radiochemistry Society
Webelements, online data base of everything elemental
Webmineral, an online mineral data base
Mineralogy links from the University of Wuerzburg
GERM: the Geochemical Earth Reference Model (includes data and links to a vast array of planetary geochemical data)
Earthchem: portal to solid earth geochemistry data

For a list of Science Today lectures click here.  (Fall 2007, Tuesdays during College Hour -- 12:35 p.m. -- in Snygg Hall, rm. 102). 

For Earth Sciences News click here. 

updated material: 12/10/07, 4:56 p.m.