Geochronology (Geology 496/596)
Fall 2008
Lecture:TWTh 10-10:50 AM, Lind Hall 102
Lab:Th 2-4:50 PM, Hebeler 108
Instructor:Dr. Chris Mattinson
Office:Lind Hall 108D
E-mail:
Tel:(509) 963-1628
Office Hours:M 10-12 AM or by appointment
Required Text: Radiogenic Isotope Geology by Alan Dickin
Course Description: Geochronology will cover the principles, analytical methods, and interpretation of several of the most widely applied geochronologic methods. The class will emphasize how to select the most appropriate method to answer a given geological problem as well as how to evaluate and interpret data in the scientific literature. Labs will include computer exercises using real geochronologic data. Graduate students will present a 20 minute talk on application of geochronology to their research interests. Some prior knowledge of basic chemistry, physics, and mineralogy is assumed.
Student Learning Outcomes: Students will know how to: (1) evaluate and interpret geochronologic data, (2) select the most appropriate geochronologic tools to answer a given geologic problem, (3) correctly evaluate the uncertainties associated with geochronologic measurements.
Laboratories: Lab exercises are due at the beginning of lecture one week after the lab date, unless otherwise indicated. We will use the computer program Isoplot, a plug-in for Excel written in visual basic by Ken Ludwig of the Berkeley Geochronology Center. A USB memory stick will be useful for transferring files, and you are welcome to bring your own laptop computer to lab.
Late assignments: Two “grace days” are given: you may turn in one assignment two days late, or two assignments one day late without penalty. Other late assignments will be marked down 10%, 1 day late; 30%, 2 days late; 50%, 3 days late; 70%, 4 days late, and will not be accepted after 5 days. Weekends and holidays are not counted toward the number of late days.
Grading:Geol 496Geol 596
Labs and homework60%48%
Midterm exam15%12%
Final exam25%20%
Class presentation--20%
Policy on Cheating: CWU requests that we clearly state our policy regarding cheating, although we do not expect any problems in this class. You are welcome to work together on labs and homeworks, but all work must be expressed in your own words, numbers, etc.! Violation will result in no credit for the assignment involved. More egregious activities will receive harsher treatment.
Students with Disabilities: Students with disabilities who wish to set up academic adjustments should give me a copy of their “Confirmation of Eligibility for Academic Adjustments” from the Disability Support Services Office within the first week of class so we can discuss how the approved adjustments will be implemented.
Schedule:
DateLecture TopicLab Topic
Sept. 24Introduction
Sept. 25Isotope Review--
Sept. 30Radioactive Decay
Oct. 1Decay Equations and solutions
Oct. 2Mass spectrometry I: Thermal ionizationDecay experiment
Oct. 7Simple decay I: the Rb-Sr system, isochrons
Oct. 8Simple decay II: The Sm-Nd system
Oct. 9Introduction to IsoplotRb-Sr & Sm-Nd
Oct. 14Branched decay: the K-Ar and 40Ar/39Ar systems
Oct. 15Diffusion and thermochronology
Oct. 16Mass spectrometry II: Laser and Furnace heatingK-Ar & 40Ar/39Ar
Oct. 21Chain decay I: the U-Pb system
Oct. 22Interpretation and the U-Pb concordia diagram
Oct. 23Mass spectrometry III: SIMS & LA-ICP-MSU-Pb
Oct. 28Pb isotopes and the age of the Earth;
MIDTERM EXAM
Oct. 29Chain decay II: the U-series systems
Oct. 30U-series applications in different environmentsU-series
Nov. 4The (U+Th)/He system
Nov. 5The Fission-track method
Nov. 6Multi-method thermochronology, applications(U+Th)/He & FT
Nov. 11VETERAN’S DAY HOLIDAY-NO CLASS
Nov. 12Introduction to cosmogenic isotopes
Nov. 13Atmospheric production: the 14C system14C
Nov. 18In-situ production: the 10Be and 26Al systems
Nov. 19Accelerator mass spectrometry
Nov. 20Summary10Be & 26Al
Nov. 25Student presentations
Nov. 26THANKSGIVING HOLIDAY-NO CLASS
Nov. 27THANKSGIVING HOLIDAY-NO CLASS--
Dec. 2Student presentations
Dec. 3Student presentations
Dec. 4Review--
Dec. 10Final Exams due at 12:00 NOON
If you have any conflicts with the lab or exam times (midterm and final are both take-home exams), contact me within the first week of class to make other arrangements.
Reading:
Sept. 24-25Ch. 1, p. 1-4 Nucleosynthesis
Sept. 30-Oct. 1Ch. 1, p. 7-13 Radioactive decay
Oct. 2Ch. 2, p. 15-16 Mass spectrometry
Ch. 2, p. 21-14 Mass fractionation
Ch. 2, p. 24-29 Magnetic-sector mass spectrometry
Ch. 2, p. 29-32 Isotope dilution
Oct. 7-9Ch. 2, p. 34-38 Isochron regression-line fitting
Ch. 3, p. 42-51 The Rb-Sr system
Ch. 2, p. 16-17 Chemical separation methods
Ch. 4, p. 70-80 The Sm-Nd system, model ages
Oct. 14-16Ch. 10, p. 254-268 The K-Ar and 40Ar/39Ar systems
Ch. 10, p. 269-279 Thermochronology, calibration
Oct. 21-23Ch. 5, p. 101-115 U-Pb, SIMS, LA-ICP-MS
Ch. 2, p. 17-18 Chemical separation methods
Ch. 2, p. 20-21, 32-34 LA-ICP-MS
Oct. 28-30Ch. 5, p. 115-123 Pb-isotopes and the age of the Earth
Ch. 12, p. 324-329 U-Series, daughter-excess methods
Ch. 12, p. 339-343 U-series, daughter-deficiency methods
Ch. 13, p. 353-356 U-series in igneous rocks
Nov. 4-6Ch. 16, p. 451-468 Fission-track dating, thermochronology
Nov. 12-13Ch. 14, p. 383-391 Cosmogenic isotopes, 14C
Nov. 18-20Ch. 14, p. 395-398 Accelerator mass spectrometry
Ch. 14, p. 398-400 10Be; p. 414-417 26Al