GLY 6739: Tracer Geochemistry

Instructor: Jeff Ryan

Office: BSF 213; Labs: BSF 253; BSF 263

Tracer Geochemistry is that subfield of geochemistry which focuses on the use of elemental abundances and (especially) isotope ratio variations in geologic materials as tools to study both their origins, and how and why they have changed over time. We use tracer techniques to track natural earth processes, anthropogenic contaminants, and changes in climate, as well as to obtain chronological information onrocks and water bodies.

Required Texts:Faure, Isotope Geology
Faure is an excellent nuts-and-bolts text for the different isotopic systems we will want examine. The meat of our readings, however, on elemental tracers and on applications of tracers will be papers from the technical literature at the current state-of-the-art in isotope geoscience, which we will read, decypher, dissect and debate.

As we will all need copies of these papers, we need to discuss their acquisition. The Dept. will pay for a set of xeroxes to be placed in the Learning Center, where they may be copied by y'all individually. Or, we can all take turns copying relevant papers for the class each week, depending on who's topic is up (see below). Recommended Supplemental Material: Chart of the Nuclides -- $11.
(We can special order these through GE, as needed.)
--A copy of Mendeleev's Periodic Table of the Elements
(any source, but if it's been a while, you'll want one.)

The Form of the Class: A mixed bag. Depending on the topics we cover, I will give short (or not-so-short) lectures on the nuts-and-bolts behind different classes of tracers (i.e., the principles of mass fractionation for stable isotopes, geochronometric techniques for radiogenic isotopes, governing relations for fluid/rock/melt interactions as related to trace element systematics - things like that).

The rest of the session (and perhaps the session following) will be in seminar format: we will examine selections from the current literature on the uses of different chemical tracer tools. The subjects of these seminars will be set by YOU - you're in here presumably because you need to know something about chemical tracers, so each week we will examine what's known about those tracers or techniques best suited to what you need to do for your thesis or research interests. Everyone will have at least one week (and probably two) where their pet topic is the topic of the day. For those weeks where your interests are up, you get to lead discussion: with me, you choose the relevant papers, get them out to your classmates, read them in great depth (discussing them with me as you prepare), and prepare a 10-15 minute or so presentation that crystallizes the topic at hand and kicks off discussions for the day. My job will be to act as co-convener and Majority Whip: I will goad the discussion along by hurling relevant questions at ALL the participants (between the lines, read:
EVERYONE is responsible for reading the papers (and if appropriate, supporting materials from Faure's text) EVERY week -- I WILL know if you haven't). Once everyone has talked to me, I'll put together a schedule of events for the class.

Grading: , There will be no exams in this class; in their stead, I will assign problem sets as necessary to assure that everyone is up to speed on data interpretation. The problems will be rather involved, but you are allowed to (and I rather expect you will) work together to figure them out. There will be one written assignment: a short (5 pages) paper in the form of a technical article, in which you attempt to solve a significant geologic problem through the evaluation of relevant data from the literature. All of these written assignments will constitute some 60% of the grade (30% on the paper, and 30% on the problems).

The other 40% of your grade will be based on in-class performance: , degree of preparation, participation in (and attendance for) class discussions, and the quality of your presentations on those days that you lead discussions. So, if behooves you to do your advance work - help me actively in selecting the papers, and discuss them with me before your assigned seminar days (I fully expect you won't understand them completely on the first read, so come and talk to me about them early!!).

3) Potential Extras: If there is interest, we may be able to swing a "field trip" up to the National High Magnetic Field Laboratory in Tallahassee, where my former professor, Dr. Alan Zindler (erstwhile of Florida State University) has an extensive state-of-the-art isotope laboratory. This would require some coordination, as to do the visit and the drives is probably a two-day deal. If the subject matter merits, we may also do some on-campus activities on my DC Plasma Spectrometer, or with the ICP- Mass Spectrometry facility on the St. Petersburg campus, both of which are cutting-edge tools for elemental analysis.

Evaluation: There will be no exams; your work in the lab will substitute for that. Along with the labwork, there will be a series of problem sets related to aspects of the lecture material (data statistics, machine calibration and data reduction methods), that all will perform.

Topics Covered: The first 2-3 sessions will be mine, as I give lectures and readings to get y'all up to speed on the mechanics of tracer studies. (This also gives me time to talk with all of y'all and construct a schedule of events). I'm personally interested in examining a couple of relevant topics (listed below): if someone else wants to pick them up, Marvelous! If not, we'll cover them on unclaimed weeks. I reserve the right to sweeten any week's topic with one other relevant article (usually to put a twist on matters).

Seminar Topics for 1997

Seminar 1 Topic and Papers

Seminar 2 Topic and Papers

Seminar 3 Topic and Papers

Seminar 4 Topic and Papers

Professor's pet Topics::

-- The use of Rare Earth Elements in studies of terrestrial systems over a wide P-T-PH2O range. Magmatic rocks, hydrothermal and ore systems, volcanic island hydrologic approaches, etc.

--Cosmogenic Radionuclide studies: 10Be, 26Al, and 36Cl in surficial and deep Earth materials. Applications in erosion rate studies, cosmic ray exposure dating, and studies of marine sedimentation.

--U-series disequilibrium isotopes: 226Ra, 230Th, and others. Applications to tracking slab-derived components in the deep mantle and to carbonate geochronology.

--Light element abundance systematics (my specialty!) Li, Be and B as tracers in water/rock/melt systems.

11/10B, 7/6Li in studies of submarine alteration and the precipitation of marine carbonates.

"Traditional" Stable Isotopes: 13C, 18O, 15N, D/H, 3/4He, and the Noble Gas systems. Many, many applications!

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