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