HR: 09:45h
AN: H51B-08    [PDF]
TI: One Year of Massive Fluid Production Test in KTB Pilot Hole, Germany
AU: Erzinger, J
EM: erz@gfz-potsdam.de
AF: GeoForschungsZentrum, Telegraphenberg, Potsdam, 14473 Germany
AU: * Kuempel, H J
EM: kuempel@gga-hannover.de
AF: Leibniz Institute for Applied Geosciences, Stilleweg 2, Hannover, 30655 Germany
AU: Shapiro, S A
EM: shapiro@geophysik.fu-berlin.de
AF: Free University Berlin, Malteserstr. 74-100, 12249, Berlin Germany
AB: Germany's deep drilling program KTB in the years of the pre-surveys (1984 - 86), the active drilling phase (1987 - 94), and during operation of the deep crustal laboratory (1995 - 2000) has revealed a wealth of new geoscientific data. The full potential of the two KTB boreholes -- the 4.0 km deep pilot hole (KTB-VB) and the 9.1 km deep main hole (KTB-HB), both in crystalline environment -- has, however, not yet been exploited. A new series of in-situ experiments on the kilometer scale, addressing relevant open questions on hydrogeological, geochemical, rock mechanical, and other issues has started in 2002 under the new program 'ENERGY AND FLUID TRANSPORT IN CONTINENTAL FAULT SYSTEMS'. The activities are focused on large scale fluid production and injection tests in two major fault systems, at 4 km and 7.2 km depths. They are part of Germany's contribution to the International Continental Drilling Programme (ICDP). A massive fluid withdrawal test in the fault system at 4 km depth took place from June 2002 till June 2003. The average yield during the test was 50 l/min brine, with similar amount of gas, mainly N2; draw down was more than 600 m. In-situ permeability and fluid availability were found to be significantly larger than anticipated. We did not observe any significant changes in the concentrations of dissolved fluid constituents. Isotope ratios were constant throughout the production period. Rare earth element concentrations of the produced fluids were extremely low. A down-hole seismometer in the KTB-HB has detected a number of small seismic events near the active KTB-VB, presumably triggered by the hydraulic forcing. The second phase of this new series of KTB experiments is planned to start in April 2004 and will include a massive fluid injection test in the KTB-VB, lasting for again 12 months. Monitoring and analysis of induced microseismicity and the detectability of other geophysical observables will be key issues. International partners who are interested in the coming or future experiments are most welcome to participate.
UR: http://www.icdp-online.org/sites/ktb/index/index.html
DE: 1806 Chemistry of fresh water
DE: 5104 Fracture and flow
DE: 5139 Transport properties
DE: 8045 Role of fluids
SC: Hydrology [H]
MN: 2003 Fall Meeting