Laboratory for Sediment Geochemical Analysis and Tephra Analytics

(1) Ion-exchange and 'reversed phase' Liquid Chromatography (Dionex)

  • Application of isocratic and gradient methods
  • Analysis of surface and ground water, pore water, aqueous leachates of soil and dust samples, and organic extracts
  • Electrical conductivity detection after chemical micro-membran suppression
  • Spectrophotometric UV/VIS detection
  • Pulsed amperometric detection

(2) Spectralphotometry - UV/Vis Spectrometer Lambda 2 (Perkin Elmer)

  • Analysis of liquid samples, recording of time and wavelengts scans

(3) Flow-Injection-Analysis, FIAS 200 (Perkin Elmer)

  • Analysis of NH4, Si, PO4, NO3, NO2 in combination with (2)
  • Analysis of hydrid-forming trace elements in combination with (4)

(4) Elektrothermische AAS, Zeeman ET-AAS 4100 ZL (Perkin Elmer)

  • Analysis of trace elements in liquids and solids after acid digestions

(5) ICP-OES, iCAP 6000 series Spectrometer (Thermo Electron Cooperation)

  • Analysis of major and trace elements in water and solids after acid

(6) Quadrupol ICP-MS, Mass Spectrometer ELAN DRC-e (Perkin Elmer)

  • Trace element analysis in water and solids after acid digestion

(7) IR-Spectrometry, TOC-5000A (Shimadzu)

  • Analysis of dissolved inorganic and organic carbon

(8) Coulometry, Coulomat 702 (Ströhlein)(currently out of operation)

  • Carbonat determinations at high sample weights

(1) Gamma Spectrometry


  • Detection of 137Cs chrono-markers and recording of 210Pb and 226Ra profiles for lead-210 dating of sediments
  • Activity measurements of dust samples
  • 222Rn activity measurements of water samples after purging and enrichment on cooled charcoal cartridges
  • 226Ra activity determinations of water samples after solid phase extraction
  • Total activity determinations of sediments for Luminescence dating purposes


  • High-purity Germanium well type detectors with offset preamplifiers and U-Style cryostat configuration (Canberra), analog electronics
  • High-purity Germanium well type detectors with offset preamplifiers and U-Style cryostat configuration (Canberra), digital electronics
  • C Broad-Energy Germanium detector with offset preamplifier and vertical cryostat configuration (BE-serie, Canberra)
  • High-purity coaxial detector with vertical cryostat configuration (GEM-series, E&G ORTEC) (currently out of operation)

(2) Alpha Spectrometry


  • Determination of α-emittents after radiochemical separation and electroplating
  • Activity determination of Po-nuclides for lead-210 dating purposes
  • Activity determination of 238-serie nuclides von solids and fluids after seperation
  • 235U/238U determinations


  • Alpha Analyst with eight A-series PIPS detectors (Canberra)

(3) Liquid-Scintillation Spectrometry


  • 222Rn determinations after extraction for detection and modelling groundwater discharge into surface waters


  • Triathler (HIDEX, Finnland) (currently out of operation)

Portable instrument for lab and field measurements with lead-shielding of the measuring chamber and α—liquid scintillation counting on the basis of α/β decay discrimination using the different extinguish time of induced photo-peaks.

Procedures, devices and applications

  • Separation of grain-size fractions based on classical methods
  • Gravimetric determination of grain-size fractions
  • Analysis of grain-size distributions using Laser-Particle-Analysis, Mastersizer 2000 (Malvern) (currently out of operation)
  • Solid density determinations of sediments and soils used for porosity analysis and analysis of specific particle surfaces, Helium-Pycnometer AccPY 1330 (Micromeritics) (currently out of operation)
Laminated sediment core from the lake Lago Grande di Monticchio (Italy) with clearly visible Tephra layers (for example at 16, 20, 34 and 52cm) (photo GFZ)
Dissolution of salts in heated shaking water bath (photo Becker)
Geochemical treatment with acids (photo Schwab)
Geochemical treatment with acids (photo Schwab)
Sieving of geochemically treated samples (photo Schwab)
Sieving of geochemically treated samples (photo Schwab)
Mineral separation according to density with heavy liquids (photo Schwab)
Transmitted light images of tephra glass shards from TSK (Lake Tiefer See Klocksin, N-Germany) and JC (Lake Czechowskie, N-Poland) sediments. Chemical composition correlates with the islandic Askja-AD1875 eruption. Changed after Wulf et al. (2016) in Quaternary Science Reviews 132.

What is tephra?

Tephra, the Greek word for ash, is used to describe any material that is ejected by a volcano into the atmosphere (pyroclasts). Tephra includes dense blocks and bombs (>64mm), and lighter materials such as scoria, pumice and ash (<2mm). As one moves away from a volcano, the tephra deposits become finer grained (smaller particles) and thinner. This is because small airborne particles hover longer and stay within the atmosphere for a greater distance from the volcano. These particles of ash can be carried in the atmosphere for thousands of kilometers. The smallest particles are so-called crypto-tephra and are invisible to the naked eye.

In the laboratory for tephra analytics, samples taken from lake sediment cores are prepared for the identification and geochemical analysis of individual cryptotephras (glass shards). Identified cryptotephras are a prerequisite for the creation of a tephrochronology that allows the independent dating of our palaeoclimate and environmental archives.

Procedures, devices and applications:

  • Dissolution of salts in heated shaking water bath
  • Geochemical treatment with acids
  • Wet-sieving to separate different size fractions (using mesh frames)
  • Split into different density fractions using heavy liquid
  • Microscopic analysis, identification of glass shards of tephra with a Binocular (Zeiss Jenapol)
  • Separation with a Binocular (Zeiss Jenapol) or a Micromanipolator
  • Embedding of glass shards in resin and manual preparation of a polished section
  • Obtaining of major element composition of single glass shards on carbon-coated stubs at a JEOL JXA-8230 microprobe


Georg Schettler
Dr. Georg Schettler
Climate Dynamics and Landscape Evolution

Contact: Tephra Analytics

Markus Schwab
Dr. Markus Schwab
Climate Dynamics and Landscape Evolution
Building C, Room 455
14473 Potsdam
+49 331 288-1388