Users include bachelor-, master-, PhD students, postdocs and other research staff from Vrije Universiteit Amsterdam and a large number of national and international universities and research institutes. We also provide services to various consultancy companies on a commercial basis.
Current instruments and facilities for conducting and/or assisting with analyses of terrestrial and marine sediments include:
Multi-Sensor Core Logging:
Our GeoTek Multi-Sensor Core Logger includes a gamma-ray attenuation porosity evaluator (GRAPE) and compressional wave (P-wave) logger device that measure bulk density, porosity and sonic velocity. It also has two Bartington magnetic susceptibility loops for different sized cores as well as a Bartington point sensor for running on split cores. The GeoScan line scan camera attached to the MST has three individual filters that produce RGB colour spectra and profile data as well as very high resolution digitized images that are available for studies involving sediment colour changes.
Grain-Size and Shape Analysis:
We do grain-size analysis using a Sympatec HELOS KR laser-diffraction particle sizer that allows for grain size measurement in the range 0.15-2000 microns. Combined grain-size and grain-shape analysis in the range 2-2000 microns is done using a Sympatec QICPIC dynamic image analyser.
The QICPIC instrument is equipped with a high performance camera and data compression module which supports the grabbing of up to 25 images of the suspended sediment particles per second, resulting in the storage of size and shape data of up to a few million individual particles per sample in just a few minutes time. The software offers simultaneous calculations of different particle size and shape characteristics. A particle gallery in combination with multiple filter functions supports the evaluation of the measured sediment sample, even if very large amounts of several million particles per sample are stored.
Thermo-Gravimetric Analysis (TGA):
Our LECO 701 TGA instrument enables the simultaneous determination of Loss-On-Ignition (LOI) on multiple samples. By using a controlled atmospheric composition within the oven we are able to distinguish several characteristic parameters of the individual samples.
Generally, the precise determination of the changing weight of 19 samples positioned in a rotating carrousel while heating over a temperature range from ~25 to 1000 °C allows the analyses of their moisture, organic matter and (calcium-)carbonate content. Both versatile and rapid (~5 hrs/run) this technique serves as a robust basic analytical tool for diverse material composition. Typical sample amount necessary for a reliable analysis is 2 gram of homogenized material. Over 10 years of experience using the TGA on a very wide variety of sediments allows us to provide you with insightful information in addition to the precise analytical results.
CNS Elemental Analysis:
We apply our Thermo Finnigan CNS Elemental Analyser to the determination of carbon, nitrogen and sulphur in (organic) sediments. C/N and C/S ratios which are used to establish organic matter provenance, diagenesis and or maturity can be determined with a precision of better than 5% on ~10 mg of material. The preparation involves besides the grinding and homogenization of the sample material also the removal of inorganic carbonate in an HCl atmosphere.
Paleobotanical methodologies:
Plant macrofossil analysis is a paleobotanical methodology that can be applied on its own or in combination with pollen analysis. Plant macrofossils are used to reconstruct local vegetation and environmental (including climate) changes from terrestrial records such as peat deposits and lake sediments. In addition, for plant groups that are difficult to assess via pollen analysis, macrofossil analysis can provide a solution (e.g., mosses). Macrofossils can usually be determined to a higher taxonomic rank than is the case with pollen analysis.
The preparation methods for the plant macrofossil analyses are as follows. The volume of samples is determined in order to quantify the different plant macrofossil types. Samples are then soaked or gently heated in a 5% NaOH or KOH solution after which the sample is washed through a sieve (150 to 250 µm) or a series of superimposed sieves (e.g., 2 mm, 1 mm, 0.5 mm, 0.25 mm).
Microscopic examination is performed with a stereomicroscope (binocular), using botanical keys and reference literature, as well as a reference collection of recent seeds and fruits. Data are plotted using Tilia and Tilia graphing software.
Pollen analysis is a valuable tool for the reconstruction of past vegetation and environments. Its application in such areas as climate change studies, earth sciences, archaeology and forensic science is therefore widely known. Good environmental conditions are important for the preservation of fossil pollen grains. For microscopic examination of pollen careful preparation of a pollen slide is crucial.
We apply several pollen preparation methods as the preparation technique must be related to the different matrices in which the pollen may be embedded. Pollen and spores counts are based on fixed pollen sum. For absolute counting we therefore use the exotic marker grain method.
Our equipment for counting pollen, spores and plotting pollen diagrams consists of: Zeiss Akloskop, Zeiss Axioscop 50 equipped with a Leica DFC 420 digital camera, Easy count (an electronic counting sheet), Research Assistant 5 professional (pollen database) and Tilia and Tilia.graph (plotting program).
Contact
In case you want to know more about possibilities and prices, please feel free to contact us!
Martine Hagen
Telephone: +31 20 59 87378
Email: m.hagen@vu.nl
Room nr: M-420
Dr. Maarten A. Prins
Telephone: +31 20 59 83635
E-mail: m.a.prins@vu.nl
Room nr: F-454