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Dear Colleagues: Here's an announcement for a short thermochronology workshop for students that we'll have here next June, in case you have any interested students. Thanks, Pete HeDWaAZ 2007 Announcement Helium Dating Workshop at Arizona (HeDWaAZ 2007) is a two-week thermochronology workshop with an emphasis on methods and interpretations of (U-Th)/He chronometry. It is aimed primarily at students from undergraduate institutions who are working on their senior theses (or similar final projects) in the summer prior to their last year of studies. The goals of the workshop are 1) to provide an opportunity for students to perform (U-Th)/He analyses on their own samples, related to projects and/or field areas that are part of their larger research project, and 2) to provide some training and experience in the fundamentals of geochronology/thermochronology, diffusion, and analytical techniques, as well as an appreciation for the versatility of thermochronologic approaches in studying a range of geologic processes. HeDWaAZ 2007 will run 13-27 June (arrival and departures on 12 and 28 June). The instructors will be Peter Reiners and Stuart Thomson, with help from Stefan Nicolescu. and will accommodate 6-7 students. Room and board on campus at the University of Arizona will be provided as part of the workshop, through NSF support. More information on the program is provided below, or at the following website: http://www.geo.arizona.edu/~reiners/HeDWaAZ/HeDWaAZ.htm Participating students will be selected based on applications comprising a short project proposal and a letter of recommendation from a faculty advisor. Applications are due no later than 31 January 2007. Applicants will be notified of the outcome of their application no later than 20 February 2007. Applications for HeDWaAZ 2007 should include a 2-3 page description of the background, methods, expected results, importance, and other information on the student's proposed thermochronometric work, and how it complements the larger body of work that will be their senior thesis or other research project at their own institution. In addition, applicants should have their faculty advisor send a letter of recommendation. Applications from students between their junior and senior years are generally preferred (because we prefer work that will be incorporated into senior theses or similar projects), but applications from students at other stages will also be accepted. Send electronic materials or questions to: [log in to unmask] More HeDWaAZ 2007 Info Rationale and general description The goal of this workshop is to introduce undergraduate geology students to (U-Th)/He chronometry and radioisotopic dating through analysis and interpretation of their own samples and data, in the context of their own research projects. Through both hands-on analyses and interpretations, as well as daily informal lectures, students will learn fundamentals of radioisotopic dating, laboratory techniques, analytical instrumentation, basics of heat and mass diffusion modeling, and something about each others' research projects and the versatility of thermochronometry. Each student's project during the workshop will focus on a small set of samples to be dated by (U-Th)/He methods. Ideally, a student's accomplishments at this workshop should complement a larger research project such as a senior thesis or other type of independent research supervised by the student's faculty advisor at his or her home institution. Examples of potential workshop projects include apatite or zircon He dating of a small group of samples (5 to 10) intended to: [a] elucidate spatial and temporal patterns of erosion or tectonic exhumation in a regional tectonic or geomorphologic study; [b] date detrital crystals in a sedimentary basin to constrain provenance or depositional age; [c] date a bolide impact site, volcanic unit, or other thermal event. Creative and experimental applications are encouraged, including attempts to measure helium ages on phases not typically analyzed, such as pseudotachylite, glass, uraninite, magnetite, etc., or attempts to constrain timing and intensity of hydrothermal heating. Important points [1] Unless other arrangements have been made, students must arrive with mineral separates already prepared and ready to pick under the microscope. We will not perform mineral separations here, so please insure that mineral separates of sufficient quality and quantity are completed and available well before the workshop starts. If students and/or their advisors are unsure about the suitability of their mineral separates, they should consult us. [2] Students (and their faculty advisors) should be prepared for the possibility that their chosen samples/field area may not have useable material for (U-Th)/He dating. This is especially important for apatite He dating, as the method has stringent requirements of crystal morphology and purity. Please have a backup plan. [3] There is no requirement for direct faculty involvement in the workshop, beyond general supervision of student research and help with data interpretation at the student's home institution. If faculty would like to attend and participate in the workshop however, they are certainly more than welcome at any point, to learn about the technique and to facilitate future use of the lab by other students or themselves. Accomodations, food, other logistics Room and board will be provided through NSF support of the workshop. Students will stay in residence halls and meals will be provided in dining halls on campus at the UofA. In general students or their home institutions or departments must pay for travel to Tucson, though some exceptions may be considered for special cases. Tentative schedule The general daily routine will be a combination of laboratory work and one or two one-hour lectures, broken up by lunch. There will be one day of a local field trip, and, time permitting, one day off. After a day of orientation, lab safety training, and some general introductory stuff, we will start with sample preparation. This mostly involves sample picking under the microscopes for the first few days. Because we only have a few picking microscopes, and also because no one can or wants to pick for more than a few hours at a time, students will take turns picking, and doing some preparatory literature or modeling research in the first few days. As samples become ready, students will process them on the He lines. This means running the lasers to extract He, and operating the programs that spike, purify, and measure the gas. Students will then perform wet chemistry involved with spiking, dissolution, and measurement of U, Th, and Sm on a high-resolution ICP-MS. After calculating ages from their measured data, and making corrections for alpha ejection, students will learn how to interpret He ages, in terms of forward and inverse thermal models, complexities that arise from topography, non-constant geothermal gradients, and other factors. Finally, students will compile and synthesize their data and relate them to their larger project, and prepare a short (20 minute) presentation for the group on their results. HeDWaAZ 2007 is funded by the NSF Tectonics and Petrology and Geochemistry Programs. ----------------------------------------- Peter W. Reiners Department of Geosciences University of Arizona Gould-Simpson Building #77 1040 E. 4th St. Tucson, AZ 85721 email: [log in to unmask] web: http://www.geo.arizona.edu/~reiners/ office: 520-626-2236 fax: 520-621-2672