New X-ray Fluorescence (XRF) Core Scanner

Figure: Left (A): AVAATECH XRF Core Scanner at AWI Potsdam; right (B): Three parallel cores for scanning procedures (Fotos: Boris Biskaborn, AWI, 2022).

Since March 2022 we measure our sediment cores with a new X-ray Fluorescence (XRF) Core Scanner. The scanner represents the fourth generation of XRF Core Scanners from AVAATECH, and was financed by the Potsdam InnoLabs for Arctic Research. The device sensors trace the elment geochemistry (XRF), magnetic susceptibility (MagSus), and high-resolution RGB color data next to distortion-free core images. Up to three parallel core halves can be measured in a multi-run-step mode (down-core step size can be lower than 1 cm).

Contact: 

• Scientific responsibility: Bernhard Diekmann

• Technical responsibility: Andreas Marent

• Functional and scientific supervision: Boris Biskaborn

 

Methods for Arctic Lake Research

Lakes in high latitudes provide a range of ecosystem services to northern communities. These lakes are variable at a range of time-scales. We combine observations of modern ecosystem state with investigations of lake dynamics.  

We apply a broad range of methods:

Contact

Dr. Boris K. Biskaborn

Coring Technique

We mainly use UWITEC coring technique: piston coring system to retrieve long cores, gravity coring to retrieve short cores with intact surface layers. We prefer winter ice condition to retrieve long cores through ice holes facilitated by stable position above ground. During summer we operate our systems from a raft. Sediment cores are transported at 4°C to AWI laboratories to analyse elements by XRF core scanning, mineral composition by XRD analysis, grain size distibution by laser particle sizing, organic contents using a VarioMAX. We analyse pollen, diatoms and chironomids and the ancient DNA.

Lake Coring

 

UWITEC Niederreiter HYBRID 90 mm Piston Coring system

  • Modell UHP 30450
  • Recovery: up to 55 m cores (reported max. so far)
  • Core diameter is 90 mm
  • Piston coring technique fixed at lake bottom
  • Applicable at up to 300 m water depth
  • Performs on ice and water
  • Strong penetration of sand layers by motor driven hammering with 100 kg weights
  • Approx. weight for summer expedition: 3 t
  • Approx. weight for winter expedition: 2 t

UWITEC 60 mm Piston Coring system Short cores and surface samples

  • Recovery: ca. 15 m cores
  • Core diameter is 60 mm
  • Piston coring technique fixed at tripod on ice or on floating platform
  • Applicable at up to 100 m water depth
  • Performs on ice and water
  • Manual hammering with variable weights
  • Approx. weight for summer expedition: 2 t
  • Approx. weight for winter expedition: 1.5 t

Short cores and surface samples

  • UWITEC Gravity Coring System 60 and 90 mm
  • Retrieval of intact surface sediments
  • Works in winter and summer
  • 60 cm length of cores for best possible surface layer conditions
  • Optinal hammer modification for up to 3 m length

 

Contact
Boris K. Biskaborn

UWITEC Hybrid 90 mm

UWITEC Piston 60 mm

UWITEC Gravity Corer

Water chemistry

We use portable water chemistry analysers to measure temperature, pH, oxygen, and conductivity on-site. Samples are transported to our laboratories in Potsdam/Germany or partner institutes to measure ions, cations, and water isotopes.

Expeditions

We perform expeditions every year to polar regions, with main interest in the Eastern Arctic. In winter we use trucks on winter roads, that is frozen rivers and lakes, to reach remote lake sites. In summer we use helicopters, because the absence of roads on thawing permafrost does not allow the use of cars.

Yakutia 2016

Bykovsky 2017

Chukotka 2018