Results from crosshole geoelectric and surface seismic monitoring for geological storage of carbo... more Results from crosshole geoelectric and surface seismic monitoring for geological storage of carbon dioxide (CO2) were investigated by forward modelling within the framework of the CO2SINK project. Selected geological and petrophysical parameters reflect the conditions of the CO2SINK site. CO2 saturation distributions were derived from multiphase flow modelling, whereas the alteration of geophysical rock properties by CO2 was obtained from
ABSTRACT For the utilization of deep saline aquifers in the frame of geotechnical use, such as ge... more ABSTRACT For the utilization of deep saline aquifers in the frame of geotechnical use, such as geological sequestration of CO2, H2 or energy storage, a baseline characterization of pristine reservoir rock cores is required to monitor changes in the indigenous microbial communities and pore fluids, and to study alterations in rock characteristics resulting from interaction with geological storage technologies. However, drilling procedures and technical fluids, particularly drill mud, are sources of core contamination. To measure the penetration of drill mud into the cores, three tracers (fluorescein, microspheres, and 4′,6-diamidino-2-phenylindole stained bacteria) were tested under laboratory conditions. The flow of drill mud into core samples was induced by applying uniaxial pressure differentials to the core, and the penetration depth was microscopically determined for each tracer. Fluorescein was extracted from the rock samples and quantified fluorometrically. The results indicate that all tested tracers are suitable for tracking drill-mud penetration. The actual penetration depth seems to be related to differences in mineral composition and texture as well as microfractures. Among all tested tracers, fluorescein labelling is the simplest, cheapest and most accurate method for analyzing the contamination of rock cores by technical fluids. The application of this tracer was successfully applied during two deep drilling campaigns at the CO2 storage pilot site in Ketzin, Germany. The results highlight that the use of tracers is indispensable to ensure the quality of core samples for microbiological and biogeochemical analysis.
New values of surface heat flow are reported for 13 deep borehole locations in the Northeast Germ... more New values of surface heat flow are reported for 13 deep borehole locations in the Northeast German Basin (NEGB) ranging from 68 to 91 mW m−2 with a mean of 77±3 mW m−2. The values are derived from continuous temperature logs, measured thermal conductivity, and log-derived radiogenic heat production. The heat-flow values are supposed free of effects from surface palaeoclimatic temperature variations,
A3D25-foldseismicsurveywithabinsizeof12by12 m and about12 km 2 ofsubsurfacecoveragewasacquiredin2... more A3D25-foldseismicsurveywithabinsizeof12by12 m and about12 km 2 ofsubsurfacecoveragewasacquiredin2005neara former natural gas storage site west of Berlin, as part of the five- year EU funded CO2SINK project. Main objectives of the seis- mic survey were to verify earlier geologic interpretations of structure based on vintage 2D seismic and borehole data and to map, if possible, the reservoir pathways in which the CO2
... Therefore, brine permeability was measured at different pressure steps between 50 and 85 bar.... more ... Therefore, brine permeability was measured at different pressure steps between 50 and 85 bar. Wireline-Log Acquisition Program and Log Quality Control. Wireline logging was performed in all three wells. Whereas the openhole ...
Here we report on the framework of geological site exploration, which encompassed investigations ... more Here we report on the framework of geological site exploration, which encompassed investigations at different scales prior to and after the drilling of the three CO2SINK boreholes. Past and new exploration data are integrated to delineate at regional scale (1) the geological structure of CO2 storage formation and its overburden, including fault systems as potential fluid pathways and (2) the
ABSTRACT Exploration of geothermal resources in eastern Germany: Status and implications for an e... more ABSTRACT Exploration of geothermal resources in eastern Germany: Status and implications for an emerging geothermal industry Förster, A.1, Norden, B. 1, Förster, H.-J. 1, Fuchs, S. 1, Wolfgramm, W.2, Obst, K.3 1Deutsches GeoForschungsZentrum, Section 4.1 Reservoir Technologies, 2 GTN Geothermie Neubrandenburg GmbH, 3 Landesamt für Umwelt, Naturschutz und Geologie Mecklenburg-Vorpommern The use of geothermal energy from the deeper subsurface is confronted with two major questions: (1) at what depth occur the temperatures necessary and (2) what are the hydraulic (porosity/permeability) and thermal properties at that depth. The hydraulic parameters also are responsible for the type of geothermal use, whether it is “hydrothermal” (pumping and injecting of warm fluids without reservoir stimulation) or “petrothermal”, for which a heat exchanger at depth needs to be generated artificially by creating an Enhanced Geothermal System (EGS). In the exploration for both types of geothermal systems, boreholes (well logs, cores, and hydraulic tests) and regional geological and geophysical surveys are vital to characterize the reservoir conditions. Hydrothermal Resources The eastern part of the North German Basin (NGB) was the target for hydrothermal resource exploration since the 1980ies. The early stage of exploration concentrated on a first systematic evaluation of Mesozoic aquifers, their depth, temperature, porosity, and permeability (Katzung, 1984; Katzung et al., 1992), using the boreholes and the huge regional database of seismic data available from the former petroleum industry of the GDR (Reinhardt et al., 1986−1989; Reinhardt, 1993). Several industrial projects developed (e.g. in Waren, Neubrandenburg, and Prenzlau) profited from the results of this stage of exploration. Later on, the results of exploration were made public in the Atlas of Geothermal Resources in Europe (Hurter and Haenel, 2002). Since then, additional data became available from several projects that utilize saline aquifers for aquifer storage of energy, balneology, and spa business. A compilation of all available data on depth, thickness, and temperature of the Mesozoic “geothermal” sandstone aquifers was recently made by Feldrappe et al. (2008), and on reservoir parameters, including petrography, porosity, and permeability, by Wolfgramm et al. (2008), respectively. Temperature maps are available in the eastern NGB for the base of the Detfurth Formation (Middle Buntsandstein/Keuper), the Stuttgart (Schilfsandstein) Formation (Keuper), the Jurassic, the Middle Jurassic, and the Lower Cretaceous (from oldest to youngest). These formations comprise a depth range from about 400−2000 m (with max. temperatures of 120°C) in the northeastern part of the basin to about 1600−3000 m (with max. temperatures of 150°C) in the southwestern part, respectively. The mapped temperatures are approximated from an isotherm map at 1500 m by applying some average geothermal gradient for extrapolation of temperature to different depth. Also, “expert knowledge” was applied to qualitatively correct temperature in the vicinity of major salt structure for heat refraction effects. Thus these maps show a highly resolved temperature pattern, strongly resembling the geological structure, but the pattern itself is not grounded in such a detail on measured borehole data nor on the petrophysical properties of the rocks. Future in-depth studies are needed to elaborate the value of these maps and to advance exploration techniques to revise the mapping. Towards this goal, an approach is in development as part of the BMBF project GeoEn to calculate vertical thermal-conductivity profiles from petrophysical and high-resolution temperature logs (Fuchs and Förster, 2010). The approach also will verify the dependence of thermal conductivity of geological formations on facies changes at basin scale. This database of thermal conductivity also constitutes an excellent basis for temperature prognoses in industrial projects to come. A subarea of the Altmark gas field (Sachsen-Anhalt) studied in the BMBF project CLEAN in cooperation with GDF SUEZ will be among the first areas profiting from this approach in the near future. Thermal data in conjunction with poro-perm data are used to characterize the Rotliegend target reservoir as well as its overburden to the top of the Cenozoic. Although the model is partially based on geothermal exploration data it has a strong implication for the study of thermal processes induced by CO2 injection and for the design of technically feasible injection regimes during enhanced gas recovery operations. Petrothermal resources Petrothermal systems in the NGB, occurring in the deeper Mesozoic section and in the Permo-Carboniferous section, are practically unlimited. The only restriction for their geothermal utilization is the depth of interest and therewith, the economy of drilling and of resource development. The Groß Schönebeck research site was the first EGS…
Results from crosshole geoelectric and surface seismic monitoring for geological storage of carbo... more Results from crosshole geoelectric and surface seismic monitoring for geological storage of carbon dioxide (CO2) were investigated by forward modelling within the framework of the CO2SINK project. Selected geological and petrophysical parameters reflect the conditions of the CO2SINK site. CO2 saturation distributions were derived from multiphase flow modelling, whereas the alteration of geophysical rock properties by CO2 was obtained from
ABSTRACT For the utilization of deep saline aquifers in the frame of geotechnical use, such as ge... more ABSTRACT For the utilization of deep saline aquifers in the frame of geotechnical use, such as geological sequestration of CO2, H2 or energy storage, a baseline characterization of pristine reservoir rock cores is required to monitor changes in the indigenous microbial communities and pore fluids, and to study alterations in rock characteristics resulting from interaction with geological storage technologies. However, drilling procedures and technical fluids, particularly drill mud, are sources of core contamination. To measure the penetration of drill mud into the cores, three tracers (fluorescein, microspheres, and 4′,6-diamidino-2-phenylindole stained bacteria) were tested under laboratory conditions. The flow of drill mud into core samples was induced by applying uniaxial pressure differentials to the core, and the penetration depth was microscopically determined for each tracer. Fluorescein was extracted from the rock samples and quantified fluorometrically. The results indicate that all tested tracers are suitable for tracking drill-mud penetration. The actual penetration depth seems to be related to differences in mineral composition and texture as well as microfractures. Among all tested tracers, fluorescein labelling is the simplest, cheapest and most accurate method for analyzing the contamination of rock cores by technical fluids. The application of this tracer was successfully applied during two deep drilling campaigns at the CO2 storage pilot site in Ketzin, Germany. The results highlight that the use of tracers is indispensable to ensure the quality of core samples for microbiological and biogeochemical analysis.
New values of surface heat flow are reported for 13 deep borehole locations in the Northeast Germ... more New values of surface heat flow are reported for 13 deep borehole locations in the Northeast German Basin (NEGB) ranging from 68 to 91 mW m−2 with a mean of 77±3 mW m−2. The values are derived from continuous temperature logs, measured thermal conductivity, and log-derived radiogenic heat production. The heat-flow values are supposed free of effects from surface palaeoclimatic temperature variations,
A3D25-foldseismicsurveywithabinsizeof12by12 m and about12 km 2 ofsubsurfacecoveragewasacquiredin2... more A3D25-foldseismicsurveywithabinsizeof12by12 m and about12 km 2 ofsubsurfacecoveragewasacquiredin2005neara former natural gas storage site west of Berlin, as part of the five- year EU funded CO2SINK project. Main objectives of the seis- mic survey were to verify earlier geologic interpretations of structure based on vintage 2D seismic and borehole data and to map, if possible, the reservoir pathways in which the CO2
... Therefore, brine permeability was measured at different pressure steps between 50 and 85 bar.... more ... Therefore, brine permeability was measured at different pressure steps between 50 and 85 bar. Wireline-Log Acquisition Program and Log Quality Control. Wireline logging was performed in all three wells. Whereas the openhole ...
Here we report on the framework of geological site exploration, which encompassed investigations ... more Here we report on the framework of geological site exploration, which encompassed investigations at different scales prior to and after the drilling of the three CO2SINK boreholes. Past and new exploration data are integrated to delineate at regional scale (1) the geological structure of CO2 storage formation and its overburden, including fault systems as potential fluid pathways and (2) the
ABSTRACT Exploration of geothermal resources in eastern Germany: Status and implications for an e... more ABSTRACT Exploration of geothermal resources in eastern Germany: Status and implications for an emerging geothermal industry Förster, A.1, Norden, B. 1, Förster, H.-J. 1, Fuchs, S. 1, Wolfgramm, W.2, Obst, K.3 1Deutsches GeoForschungsZentrum, Section 4.1 Reservoir Technologies, 2 GTN Geothermie Neubrandenburg GmbH, 3 Landesamt für Umwelt, Naturschutz und Geologie Mecklenburg-Vorpommern The use of geothermal energy from the deeper subsurface is confronted with two major questions: (1) at what depth occur the temperatures necessary and (2) what are the hydraulic (porosity/permeability) and thermal properties at that depth. The hydraulic parameters also are responsible for the type of geothermal use, whether it is “hydrothermal” (pumping and injecting of warm fluids without reservoir stimulation) or “petrothermal”, for which a heat exchanger at depth needs to be generated artificially by creating an Enhanced Geothermal System (EGS). In the exploration for both types of geothermal systems, boreholes (well logs, cores, and hydraulic tests) and regional geological and geophysical surveys are vital to characterize the reservoir conditions. Hydrothermal Resources The eastern part of the North German Basin (NGB) was the target for hydrothermal resource exploration since the 1980ies. The early stage of exploration concentrated on a first systematic evaluation of Mesozoic aquifers, their depth, temperature, porosity, and permeability (Katzung, 1984; Katzung et al., 1992), using the boreholes and the huge regional database of seismic data available from the former petroleum industry of the GDR (Reinhardt et al., 1986−1989; Reinhardt, 1993). Several industrial projects developed (e.g. in Waren, Neubrandenburg, and Prenzlau) profited from the results of this stage of exploration. Later on, the results of exploration were made public in the Atlas of Geothermal Resources in Europe (Hurter and Haenel, 2002). Since then, additional data became available from several projects that utilize saline aquifers for aquifer storage of energy, balneology, and spa business. A compilation of all available data on depth, thickness, and temperature of the Mesozoic “geothermal” sandstone aquifers was recently made by Feldrappe et al. (2008), and on reservoir parameters, including petrography, porosity, and permeability, by Wolfgramm et al. (2008), respectively. Temperature maps are available in the eastern NGB for the base of the Detfurth Formation (Middle Buntsandstein/Keuper), the Stuttgart (Schilfsandstein) Formation (Keuper), the Jurassic, the Middle Jurassic, and the Lower Cretaceous (from oldest to youngest). These formations comprise a depth range from about 400−2000 m (with max. temperatures of 120°C) in the northeastern part of the basin to about 1600−3000 m (with max. temperatures of 150°C) in the southwestern part, respectively. The mapped temperatures are approximated from an isotherm map at 1500 m by applying some average geothermal gradient for extrapolation of temperature to different depth. Also, “expert knowledge” was applied to qualitatively correct temperature in the vicinity of major salt structure for heat refraction effects. Thus these maps show a highly resolved temperature pattern, strongly resembling the geological structure, but the pattern itself is not grounded in such a detail on measured borehole data nor on the petrophysical properties of the rocks. Future in-depth studies are needed to elaborate the value of these maps and to advance exploration techniques to revise the mapping. Towards this goal, an approach is in development as part of the BMBF project GeoEn to calculate vertical thermal-conductivity profiles from petrophysical and high-resolution temperature logs (Fuchs and Förster, 2010). The approach also will verify the dependence of thermal conductivity of geological formations on facies changes at basin scale. This database of thermal conductivity also constitutes an excellent basis for temperature prognoses in industrial projects to come. A subarea of the Altmark gas field (Sachsen-Anhalt) studied in the BMBF project CLEAN in cooperation with GDF SUEZ will be among the first areas profiting from this approach in the near future. Thermal data in conjunction with poro-perm data are used to characterize the Rotliegend target reservoir as well as its overburden to the top of the Cenozoic. Although the model is partially based on geothermal exploration data it has a strong implication for the study of thermal processes induced by CO2 injection and for the design of technically feasible injection regimes during enhanced gas recovery operations. Petrothermal resources Petrothermal systems in the NGB, occurring in the deeper Mesozoic section and in the Permo-Carboniferous section, are practically unlimited. The only restriction for their geothermal utilization is the depth of interest and therewith, the economy of drilling and of resource development. The Groß Schönebeck research site was the first EGS…
Uploads
Papers by Ben Norden