PhD Position at the Department of Earth Sciences at Basel University

A PhD position becomes available by 1.1.2003 in the Petrology group
at the department earth sciences of the university of Basel.

The Project
It has been known since the early eighties (Frank et al. 1983, Jb.
Hochschulschwerpunkt S15, 263-293) that the Austroalpine basement
units experienced a polyphase metamorphic evolution, which involves
pre-alpine events and a Barrowian type cretaceous event. Recent
geochronological work (Schuster and Frank 1999, Mitt. Ges. Geol.
Bergb. Stud. Österr., 42, 37-58; Schuster et al. 2001, Mitt. Ges.
Geol. Bergb. Stud. Österr., 44, 111-141) has revealed that at least
part of the pre-Alpine metamorphic overprint is of Permian age. The
Permian event was identified as a low pressure high temperature
overprint. The regional extent of the Permian event is not yet well
known but this question is of utmost importance for an understanding
of the geodynamic links among the pre-Alpine and Alpine orogeneses in
central Europe.

Identification of Permian parageneses by geochronological methods is
laborious and only possible in rare cases, where rocks have the
appropriate mineralogical and chemical characteristics. Geochronology
is not a suitable method to determine the regional distribution of
Permian mineral parageneses. The aim of the intended study is to
develop and apply an indirect tool for distinction of Permian and
older pre-Alpine metamorphism by derivation of the P-T conditions at
which “old", inherited mineral phases formed. The prime focus will be
on garnets, which frequently occur in several generations in the
Austroalpine basement units. In a specific sample, the cores of the
oldest garnet generation contain information on the P-T conditions
during incipient growth. It is known from theory and has been applied
in a qualitative sense (Faryad and Hoinkes 2002) that the relations
between garnet core chemistries and bulk rock chemistries reflect P-T
conditions during garnet growth. Even if such P-T estimates are
rather crude, they promise to allow distinction of high temperature -
low pressure events from Barrowian type events and thus provide a
means to identify the Permian age of a parageneses from its low
pressure - high temperature characteristics..

This approuch involves sampling of metapelites from several basement
units within the Austroalpine nappe system with focus on areas where
polyphase mineral assemblages have already been identified. This part
of the work will be done in cooperation with Dr. R. Schuster
(Geologcal survey of Austria). As a second step detailled petrography
of selected samples including scanning electron microscopy,
microprobe- and XRF work is needed to generate a sound data set.
These methods are run routinely at our departement in Basel. The
third step involves thermodynamic modelling of the metapelite systems
with appropriate software such as THERIAC (de Capitani and Brown
1987,  Geochim. Cosmochim. Acta 51:2639-2652) and/or PERPLEX
(Connolly 1990, Am. Journ, Sci, 290, 666-718, Connolly and Petrini
2002, Journ. of Met. Geol. 20,  697-708). This part of the study will
mainly be supervised by C. de Capitani and R. Abart. An active and
well known in house group in Alpine tectonics (S. Schmid) will also
be involved in the project.

Employment
At the departement of earth sciences of the university of Basel PhD
positions are usually funded for a maximum of four years. Apart from
research, PhD students are actively involved in teaching and
maintenance of anlaytical labs or computer infrastructure.The monthly
salary is on the order of 2000 SFr (after taxes), field expenses are
fully covered by separate funding.

Application
Applicants should have a sound background in "hard rock geology" and
in petrology and they should have an interest in thermodynamics.
Applications are invited to be sent by 15.11.2002 to Prof. Dr. C. de
Capitani or Prof. Dr. R. Abart, both at
Mineralogisch-Petrographisches Institut, Bernoullistrasse 20, CH-4056
Basel. Applications should contain a curriculum vitae, list of
publications, description of personal research interests and the
addresses of at lest two persons, who would be willing to give
personal references on the applicant.


Looking forward to your application!

Prof. Dr. C. de Capitani
Tel. ++41-61-267 3621
e-mail: [log in to unmask]

Prof. Dr. Rainer Abart
Tel. ++41-61-267 3616
e-mail: [log in to unmask]

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Dr. Romain Bousquet
Earth Sciences Department
University of Basel
Bernoullistr. 30
CH-4056 Basel - Switzerland
Ph: (41) 61 267 3632 / fax: (41) 61 267 2813
http://www.unibas.ch/earth/tecto/
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