The origin of non-hydrocarbon gases in the North-German Basin: Sources, migration paths and relative timing of nitrogen release

• Applicant: Dr. Birgit Plessen
• Subject Area: Mineralogy, Petrology and Geochemistry
• Term: from 2002 to 2009
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5370434

The nitrogen contents in gas reservoirs in the eastern part of the North German Basin locally exceeds 80%. Is it thus, one of the main obstructions which has stopped further gas exploration in these part of the basin. Possible nitrogen sources include organic matter in sediments, ammonium-bearing minerals, magmatic and/or metamorphic rocks, or mantle origin. In contrast to former studies, the planned project does not only focus on the possible sources of nitrogen but also on its migration and entrapment. Investigations will therefore include source-, reservoir-, and intercalated rocks in key wells and boreholes from different tectonic regions of the basin. A combination of methods including determination of nitrogen contents and d15N isotopic compositions of rocks and organic compounds, detailed studies of fluid inclusions (microthermometry, laser-Raman spectroscopy, anion/cation variation, ammonium contents, nitrogen and chlorine isotopic compositons) and electron-microprobe analysis is the methodical base of this project. The results will be important for the "Tight Gas reservoir Project" of the German Gas Industry and for the future of deep-gas exploration worlwide.

• DFG Programme: Priority Programmes
• Subproject of: SPP 1135: Dynamics of Sedimentary Systems under Varying Stress Regimes: The Example of the Central European Basin System
• Participating Persons: Dr. Peer Hoth; Dr. Volker Lüders; Dr. Robert Ondrak