Laboratories | University of Tübingen

Our working group currently has facilities for all stages of thin section production and analysis. Blocks of sediment are indurated in a mixture of polyester resin and styrene in a fume hood and hardened, before being sliced with a rock saw. We also have an Accutom-100 (Struers) grinding machine with integrated high-precision slicing functionality for the production of thin sections measuring 28x48mm and 50x75mm. In collaboration with the Laboratory of Soil Science and Geoecology, we have access to further induration and thin sectioning facilities and instruments, including a Uniprec Woco Top 250 A1 encapsulated diamond slitting disc and an encapsulated precision grinder (G&N MPS-RC Vacuum) which can be used to produce larger-format thin sections measuring 60x90mm.

For requests on using the induration and thin sectioning facilities, please contact either Prof. Christopher Miller (christopher.miller@ uni-tuebingen.de), Panagiotis Kritikakis (panagiotis.kritikakis@ uni-tuebingen.de)

The microscopy laboratory currently contains three microscope stations that are used for micromorphology, phytolith analysis, ceramic petrography, botanical analyses, and grain mount analysis. Low magnification observations are made using a Zeiss Stemi-2000-C stereomicroscope. High magnification observations are conducted on one of two Zeiss Axio Imager petrographic microscopes, one of which is equipped with a dual viewer for teaching purposes. All microscopes are equipped with Zeiss Axiovision digital cameras.

In addition to microscopes, the lab houses an Imaging Workstation that can be used to process large digital images and datasets, including GIS, elemental mapping data, composite photomicrographs, and photogrammetry. Additionally, this laboratory contains a fume hood, high-precision scale and centrifuge for phytolith extraction and grain-mount production.

For requests on using these facilities, please contact Prof. Christopher Miller (christopher.miller@ uni-tuebingen.de)

The Microanalytics laboratory focuses on Fourier transform infrared spectroscopy (FTIR) and X-ray fluorescence (XRF). There are several instruments that are aimed at the analysis of materials in thin section.

A Cary 610 (Agilent Technologies) benchtop FTIR is equipped with both KBr and Mylar beamsplitters, and mid-infrared and far-infrared detectors. Analyses can be conducted in transmission mode using powders prepared into KBr pellets, or on straight powders or sample surfaces using the diamond-crystal ATR accessory equipped with a camera (Gladi-ATR; Pike Technologies).

Micro-FTIR analyses are conducted using the Cary 670 (Agilent Technologies) FTIR microscope. Analyses are possible in transmission mode, reflectance mode, or from direct contact with the thin section surface using either a germanium ATR objective or diamond crystal ATR objective.

The Bruker M4 Tornado, is a micro-XRF which is equipped with a rhodium x-ray source and dual detectors for fast mapping of thin sections. Elemental detection starts with Na.

Various software packages on four computers are used for the processing of FTIR and micro-XRF data, including PLS Toolbox for Matlab, which allows for the development of classification models and semi-quantitative analysis of FTIR spectra. The lab has an in-house spectral library of archaeological materials analyzed as powders using a diamond ATR, and as reflectance spectra from thin sections.

For more information about using this facility, please contact Dr. Susan Mentzer (susan.mentzer@ ifu.uni-tuebingen.de)

In addition to the instruments in the Microanalytics Laboratory, we have several portable instruments that allow us to conduct analyses in the field. We have two Cary 630 (Agilent Technologies) portable mid-infrared FTIR instruments with interchangeable sampling accessories that allow us to analyze materials in transmission, reflectance and ATR modes. These instruments can be checked out to use in a personal office, museum visit, or even in the field with our optional external battery pack and field laptop. In addition, we have several portable Motic petrographic microscopes that can be taken into the field for the purposes of analyzing expedient grain mounts or observing micromorphology samples from previous field seasons. For even more expedient observations, we are currently experimenting with inexpensive pocket microscopes. Our researchers can prepare phytolith samples for observation in the field using a Roth portable centrifuge.

In addition to our portable analytical instruments, we also have a full range of standard field equipment for survey and sampling, including a dynamic cone penetrometer (DCP K100-DE). Together with the Geoinformatik Working Group we also have an SRI 4000 (GSSI) ground-penetrating radar. As a member of the GeoRadar Forum we have access to a range of antennae.

For access to any of the field equipment or instruments, please contact either Prof. Christopher Miller or Dr. Susan Mentzer.

Laboratory Facilities

Micromorphology Laboratory

Microscopy Laboratory

Microanalytics Laboratory (FTIR/XRF)

Field Laboratory