In-situ Durchlässigkeitsbestimmung von Deckgesteinsformationen zur Untertagelagerung von Kohlendioxid mittels Edelgasanalysen an Porenwässern frischer Bohrkernproben

• Applicant: Dr. Johanna Lippmann-Pipke
• Subject Area: Mineralogy, Petrology and Geochemistry
• Term: from 2002 to 2005
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5393908

Water originating from the ultra deep of the Earth's crust is extremely difficult and costly to sample, but its noble gas analysis enables to determine its subsurface residence time, to identify governing transport mechanism and mixing ratios. Such fundamental knowledge will significantly enhance our understanding in respect to the quantification of deep, long term, fluid flow on preferential pathways like fractures and faults, and its effects on geochemical cycles, like in example the mechanism enabling long term and continuous "supply of food" for early life forms in the deep subsurface. Within three new (A) or ongoing (B and C) international research projects such exceptional deep water samples are accessible: (A) Results of the pore water analysis from fresh cores drilled through cap and reservoir rock of envisaged subsurface CO2 sequestration sites have the potential to contribute to influence policymakers in respect to safe and long-term greenhouse gas emission reduction (e.g. the Frio Formation, TX, USA; in coop. with Prof. G. Born, GFZ Potsdam). (B) A one year pump test performed at the pilot hole of the KTB test site will provide for the first time such highest quality, uncontaminated fluids from an intersected water bearing fissure in about 4km depth (Continental Deep Drilling Project, Germany, in coop. with Prof. J. Erzinger, GFZ Potsdam). (C) First results from 18 fissure and pore water samples from the ultra deep South African gold mines (below 3km, in coop. with Prof. T.C. Onstott, Princeton Univ., USA; Prof. M. Stute and Prof. P. Schlosser, LDEO, Columbia Univ., USA) were recently summarzied (Lippmann et al., 2002) but more of such unique water samples are available or will be sampled throughout this year.

• DFG Programme: Research Grants