Head of working group

Prof. Dr. Gudrun Massmann


AG Hydrogeologie/ Landschaftswasserhaushalt 
IBU, Fk. V, Gebäude A1 
Carl von Ossietzky Universität 
D-26111 Oldenburg


Renate Kettmann 
Raum: A1 1-130 
Tel.: ++49 (0) 441 / 798 - 4236 
Fax: ++49 (0) 441 / 798 -3769 

Janek Greskowiak

Dr. Janek Greskowiak

Research scientist

phone: +49 (0) 441-798-3260
Fak.V, IBU, A03 1-110



Scientific Career and Education



Research Scientist at Carl von Ossietzky University Oldenburg, Institute for Biology and Environmental sciences


Visiting Scientist, US Geological Survey, Menlo Park, CA

07/2008 - 07/2010

Post-doctoral research fellow at CSIRO Land and Water, Perth, Australia

01/2006 - 06/2007

Research scientist at Kompetenz Zentrum Wasser Berlin, gGmbH, Berlin

12/2005 - 12/2006

Post-doctoral research fellow at the Center of Geoscience, Universität Göttingen


Dissertation, Alexander von Humboldt University of Berlin



"Reactive transport processes in artificially recharged aquifers - Field and modelling studies"

08/2002 - 01/2003

Visiting scietist at Flinders University, Adelaide and at CSIRO Land and Water, Perth, Australia

2002 - 2005

PhD-student at Leibniz-Institut für Gewässerökologie und Binnenfischerei, Berlin


Graduation/Diplom in Geology, University of Potsdam

Scientific interests

My research interests are to understand and model coupled flow and reactive transport processes in groundwater focussing on the following topics:

  • Surface water - groundwater interaction
  • Managed aquifer recharge (river bank filtration, soil aquifer treatment, aquifer storage and recovery)
  • Contaminant reactive transport of organic micro- and macro-pollutants, and radionuclides
  • Coastal hydrogeology

For the investigation of reactive transport processes I mostly use the simulation tool PHT3D (, reactive transport code for saturared porous media which is based on the reaction model PHREEQC-2 and the multi species transport simulator MT3DMS. The PHT3D code is steadily updated and tested with new applications and benchmark examples by the authors Henning Prommer (CSIRO, Perth), Vincent Post (Flinders University, Adelaide) und Jungho Park (CSIRO, Perth) and a large number of collaborators.

Movies of some simulations can be found here

(Changed: 2021-04-30)