Suitable host rocks for a repository for high-level radioactive waste (HLW) in Germany include no... more Suitable host rocks for a repository for high-level radioactive waste (HLW) in Germany include not only clay and crystalline rocks but also rock salt formations in so-called flat and steep bedding (StandAG, 2017). Favourable repository relevant properties of rock salt are, e.g. the high heat conductivity, low porosity and permeability, and its viscoplastic deformation behaviour. Thicker salt deposits can be attributed to the formation of approx. 700 salt structures that have formed under various geological conditions in the North German Basin (NGB) over the last 250 million years. According to their shape and genesis, salt structures are classified as salt pillows (considered as flat bedding) or salt diapirs (steep bedding). Out of a total of 74 sub-areas in rock salt, 60 sub-areas in salt diapirs consisting of Permian evaporates were identified within the first phase of the German site selection procedure (BGE, 2020). At the current stage of the site selection process, a conservative approach has been adopted and the internal structure of the salt structures have not yet been taken into account for further classification of the identified subareas. However, the interior of the salt structures not only consists of rock salt but also of varying proportions of clay, carbonate and anhydrite rocks, as well as potassium salts formed by progressive evaporation of marine brines. Multi-phase salt tectonics has led to the folding of these differently composed layers and to complex internal structures. Therefore, detailed knowledge of the salt structure compositions is necessary to identify suitable rock salt areas for the designation of the containment providing rock zone. As a result of decades of research through extensive salt and potash mining, cavern storage and exploration for final waste disposal, Permian salt rocks represent a well-studied host rock in Germany. The use of different exploration methods and multidisciplinary data evaluation have led to a comprehensive understanding of the internal composition of some well-studied salt structures. Systematic studies have shown that several factors have influenced the formation of salt structures as well as their external shapes, sizes, and spatial distribution (e.g., Pollok et al., 2020). Furthermore, the amount and distribution of suitable host rocks varies greatly in different salt structures and is closely related to their internal structure. Since the interior of salt structures has not been considered in the site selection process so far, a classification of salt structures (or sub-areas) into certain types with varying internal composition and complexity is presented. By examining their lithofacial composition, genesis, and structural geological position within the basin, it is possible to narrow down these types to specific areas in the NGB. Without the acquisition of additional exploration data in this phase of the site selection process, this salt structure classification provides important data for the legally demanded assessment of the overall favourable geological situation. Kurzfassung. Geeignete Wirtsgesteine für ein Endlager für hochradioaktive Abfälle (HAW) in Deutschland sind neben Ton-und Kristallingesteinen auch Steinsalzformationen in sogenannter flacher und steiler Lagerung (StandAG, 2017). Günstige endlagerrelevante Eigenschaften von Steinsalz sind z. B. die hohe Wärmeleitfähigkeit, die geringe Porosität und Permeabilität sowie sein viskoplastisches Verformungsverhalten. Mächtigere
With Germany’s progressive energy revolution and its transition to fluctuating renewable energy s... more With Germany’s progressive energy revolution and its transition to fluctuating renewable energy sources large scale energy storages will be required. Storage power plants may play an important role for storing excess wind or solar energy converted to compressed air (CAES) or hydrogen. However, large volumes can only be accommodated in the geological subsurface. Because of its thermo-mechanical stability, its low tendency to react chemically with the stored medium and its flexible operation modes, salt caverns represent the preferred storage option. The focus of the InSpEE project is to provide basic geological and geotechnical data, to compile criteria for the establishment of salt caverns as well as to estimate the total renewable energy storage potential of salt structures in the North German Basin. In this collaborative project, existing expertise in salt geology, rock mechanics and cavern design principles are brought together by the Federal Institute for Geosciences and Natural Resources (BGR), Leibniz University of Hanover – Institute of Geotechnical Engineering/Department of Underground Construction (IGtH), and KBB Underground Technologies GmbH. The project’s results are integrated into a publicly accessible geo information system called “Salt”. Within this paper we present an overview of salt structures in the North German Basin and their internal compositions.
Underground storage in salt structures for compressed air or hydrogen are one of the few options ... more Underground storage in salt structures for compressed air or hydrogen are one of the few options for storing renewable energy in grid scale. However, there are only insufficiently substantiated estimates of the total potential. Therefore the objectives of the InSpEE project are the development and deployment of design principles and basic geological/geotechnical data and of site selection criteria for the establishment of salt caverns as well as the estimation of the renewable energy storage potentials of the salt structures in the North German Basin. Cooperating project partners bringing in their expertise in the areas of salt geology, rock mechanics and planning and construction of salt caverns. Thermo–mechanically based assessment criteria will be applied for the site characterization and an algorithm of the estimation of the possible storage potential will be developed. Finally, a publicly accessible “Salt information system” will be provided and the estimation storage potential for caverns in NW-Germany shall be addressed. Within this paper the rock mechanical design for CAES and H2 storage in salt caverns under consideration of thermo-mechanical coupled calculations will be presented as well as the methodology and the evaluation of the storage capacity for renewable energies.
The Federal Company for Radioactive Waste Disposal (BGE), the implementer of Germany's site selec... more The Federal Company for Radioactive Waste Disposal (BGE), the implementer of Germany's site selection procedure to identify a site suitable to safely dispose of its high-level nuclear waste, recently proposed a timeline suggesting the period between 2046 and 2068 as potential time slot for the final site decision (BGE, 2022). Thus, the decision is expected to be made substantially later than envisaged by the Site Selection Act, which states that one should aim for 2031 (StandAG, 2017). The BGE document not only details the timeline resulting in a site decision by mid-century but also outlines an alternative exploration approach inspired by the Swiss site selection procedure, which-if pursued-would enable substantial time gains. The core of this approach is a paradigm shift from exploration programs designed to acquire all data legally required for the safety analyses to data acquisition explicitly aiming at a site comparison during the respective exploration phase. Consequently, full-scale exploration would only be performed for those siting regions having passed the comparison. This contribution aims to detail and discuss this approach more thoroughly, based on the BGR's experience regarding the exploration of the subsurface. It focuses on the geoscientific aspects of this approach, while neglecting others such as the legal and administrative challenges. Owing to the basic idea of this alternative exploration approach, first a set of parameters suitable to differentiate potentially "better-suited" siting regions from "worsesuited" ones has to be identified. There are two main requirements for this set of parameters, namely the (i) general acceptance by the scientific community and (ii) capability to account for the specific characteristics of the individual host rock types while (still) ensuring the comparability of different rock types.
With Germany’s progressive energy revolution and its transition to fluctuating renewable energy s... more With Germany’s progressive energy revolution and its transition to fluctuating renewable energy sources large scale energy storages will be required. Storage power plants may play an important role for storing excess wind or solar energy converted to compressed air (CAES) or hydrogen. However, large volumes can only be accommodated in the geological subsurface. Because of its thermo-mechanical stability, its low tendency to react chemically with the stored medium and its flexible operation modes, salt caverns represent the preferred storage option. The focus of the InSpEE project is to provide basic geological and geotechnical data, to compile criteria for the establishment of salt caverns as well as to estimate the total renewable energy storage potential of salt structures in the North German Basin. In this collaborative project, existing expertise in salt geology, rock mechanics and cavern design principles are brought together by the Federal Institute for Geosciences and Natural Resources (BGR), Leibniz University of Hanover – Institute of Geotechnical Engineering/Department of Underground Construction (IGtH), and KBB Underground Technologies GmbH. The project’s results are integrated into a publicly accessible geo information system called “Salt”. Within this paper we present an overview of salt structures in the North German Basin and their internal compositions.
Underground storage in salt structures for compressed air or hydrogen are one of the few options ... more Underground storage in salt structures for compressed air or hydrogen are one of the few options for storing renewable energy in grid scale. However, there are only insufficiently substantiated estimates of the total potential. Therefore the objectives of the InSpEE project are the development and deployment of design principles and basic geological/geotechnical data and of site selection criteria for the establishment of salt caverns as well as the estimation of the renewable energy storage potentials of the salt structures in the North German Basin. Cooperating project partners bringing in their expertise in the areas of salt geology, rock mechanics and planning and construction of salt caverns. Thermo–mechanically based assessment criteria will be applied for the site characterization and an algorithm of the estimation of the possible storage potential will be developed. Finally, a publicly accessible “Salt information system” will be provided and the estimation storage potential for caverns in NW-Germany shall be addressed. Within this paper the rock mechanical design for CAES and H2 storage in salt caverns under consideration of thermo-mechanical coupled calculations will be presented as well as the methodology and the evaluation of the storage capacity for renewable energies.
The radioactive waste in the former Asse II salt mine has to be retrieved prior to the legally de... more The radioactive waste in the former Asse II salt mine has to be retrieved prior to the legally demanded decommissioning. In this context, the construction of a new mine and shaft is necessary, whereby detailed geological information about the salt structure is indispensable. Knowledge of the evaporite sequence, the internal composition, and the external shape of the Asse salt structure has been significantly enhanced by drill core investigations, borehole measurements, ground penetrating radar, and a new 3D seismic survey in recent years. The combined results indicate a highly complex internal structure with intensely folded Zechstein layers, contradicting earlier geological assumptions about this part of the salt structure. Furthermore, the strong tectonic influence during salt structure development is evidenced by complex structures in the cap rock and overburden, and by the formation of a salt wing on the steep southern flank. Additionally, a considerable narrowing of the salt structure to the southeast reduces the available space for the new mine. Our research shows that planning of waste repositories in complex salt structures has to be based on reliable, site-specific geoscientific data sets to reduce the risk of complications in the construction phase.
The site selection procedure for a high-level radioactive waste repository in Germany is based on... more The site selection procedure for a high-level radioactive waste repository in Germany is based on the Repository Site Selection Act (StandAG, 2017), which comprises three phases. In phase 2, the Federal Company for Radioactive Waste Disposal (BGE) will conduct surface exploration. Based on the exploratory findings, the further developed preliminary safety analyses, the common requirements and criteria, and socioeconomic potential analyses will be applied feeding into proposed sites for underground exploration. Commissioned by the BGE, the Federal Institute for Geosciences and Natural Resources (BGR) contributes to this procedure with the projects "GeoMePS" and "ZuBeMErk", which compile and assess geoscientific and geophysical methods and programs for surface exploration. Their common goal is to develop recommendations for surface exploration of siting regions. For this purpose, the BGR has developed a systematic approach that includes (1) deducing 186 exploration targets (Kneuker, 2020) based on the requirements defined by StandAG, (2) compilation of geoscientific and geophysical exploration methods in a database structure, and (3) analysis of case studies of national and international exploration programs for high-level radioactive waste disposal. During step (2) the BGR developed the database "GeM-DB" which utilizes MS SQL Server 2017 and PHP scripts for a browser-based interface (Beilecke, 2021). Both lead to a highly customizable, user-friendly database enabling further adaptations, expansions and analyses of the contents. Merging the knowledge of about 100 BGR experts, the database currently comprises approx. 140 geoscientific and geophysical exploration methods, including basic information and essential metadata to evaluate the general applicability of the methods for surface exploration of the three defined host rocks (crystalline rock, claystone, rock salt). Additionally, the methods are rated according to their suitability for the previously defined exploration targets. An example for a method selection, which is suitable to target fault zones (exclusion criterion 2, StandAG) is given in Fig. 1. In step (3) the BGR screens national and international waste disposal programs exploring for crystalline rock, claystone, and rock salt and feeds the obtained information back into "GeM-DB". The entire systematic approach of the projects "GeoMePS" and "ZuBeMErk" aims to develop recommendations for a non-destructive and minimally invasive surface exploration program of siting regions in Germany, regarding the lithological, structural, mechanical, and hydrogeological characterization of the different host rock formations. Kurzfassung. Das Standortauswahlverfahren für ein Endlager für hochradioaktive Abfälle in Deutschland basiert auf dem Standortauswahlgesetz (StandAG, 2017), das drei Phasen umfasst. In Phase 2 wird die Bundesgesellschaft für Endlagerung (BGE) mit der übertägigen Erkundung beginnen. Auf der Grundlage der Untersuchungsergebnisse werden die weiterentwickelten vorläufigen Sicherheitsanalysen, die allgemeinen Anforderungen und Kriterien sowie sozioökonomische Potenzialanalysen angewandt, die in die Vorschläge von Standorten einfließen werden, die für die untertägige Erkundung geeignet sind. Im Auftrag der BGE trägt die Bundesanstalt für Geowissenschaften und Rohstoffe (BGR) zu diesem Verfahren mit den Projekten "GeoMePS" und "ZuBeMErk" bei, in denen geowissenschaftliche und geophysikalische Methoden und Programme zur übertägigen Erkundung zusammengetragen und bewertet werden. Ihr gemeinsames Ziel besteht in der Entwicklung von Empfehlungen für die übertägige Erkundung von Stand-Published by Copernicus Publications on behalf of the Federal Office for the Safety of Nuclear Waste Management (BASE).
The radioactive waste in the former Asse II salt mine has to be retrieved prior to the legally de... more The radioactive waste in the former Asse II salt mine has to be retrieved prior to the legally demanded decommissioning. In this context, the construction of a new mine and shaft is necessary, whereby detailed geological information about the salt structure is indispensable. Knowledge of the evaporite sequence, the internal composition, and the external shape of the Asse salt structure has been significantly enhanced by drill core investigations, borehole measurements, ground penetrating radar, and a new 3D seismic survey in recent years. The combined results indicate a highly complex internal structure with intensely folded Zechstein layers, contradicting earlier geological assumptions about this part of the salt structure. Furthermore, the strong tectonic influence during salt structure development is evidenced by complex structures in the cap rock and overburden, and by the formation of a salt wing on the steep southern flank. Additionally, a considerable narrowing of the salt structure to the southeast reduces the available space for the new mine. Our research shows that planning of waste repositories in complex salt structures has to be based on reliable, site-specific geoscientific data sets to reduce the risk of complications in the construction phase.
74th EAGE Conference and Exhibition incorporating EUROPEC 2012, 2012
Dedicated Glaciations In this paper we will document the stratigraphic evolution, internal facies... more Dedicated Glaciations In this paper we will document the stratigraphic evolution, internal facies architecture and geomorphology of regressive glacigenic deltas, controlled by rapid high-amplitude base-level change. These systems are excellent field example to test the effect of high-amplitude base-level change on glacigenic delta systems, because subsidence, compaction, wave or tides did not play a major role. A large data set, including outcrop data, borehole data and high-resolution shear-wave seismic sections can resolve architectural elements in the range of metres and bridge the common gap between outcrop and standard industrial compression wave seismic data. The objective of this work is to provide a synthesis of the stratigraphic architecture of regressive deltas, giving new insights into the controls on delta building and erosion processes. The emphasis is placed on the sedimentary facies associations, the correlation of seismic facies with boreholes and outcrops and the analysis of the larger scale stacking pattern of architectural elements. A new depositional model summarizing facies features, depositional processes and architectures is proposed that may add to the sequence stratigraphic interpretation of steep glacigenic delta systems, controlled by rapid base-level change.
The Pleistocene deposits of Schöningen represent an outstanding geological and archaeological arc... more The Pleistocene deposits of Schöningen represent an outstanding geological and archaeological archive, where an up to 45 m thick Middle to Late Pleistocene succession has been preserved and unique artefacts from the Lower Palaeolithic have been discovered. The preservation of such a thick and complete glacial/ interglacial succession is very rare in the geological record and requires a specific depositional setting. We will present a new depositional model for the Pleistocene succession of Schöningen, integrating outcrop data, borehole data and high-resolution shear wave seismics. A total of four outcrop sections and 744 borehole logs were examined to document the complex facies architecture. All collected sedimentological and geophysical data sets were integrated into a high-resolution 3D geological model (GOCAD Ò) for reconstructing the spatial distribution of facies associations and the large-scale depositional architecture. The spatial distribution of the artefacts will be discussed with respect to the depositional environment. The Elsterian and Holsteinian deposits are restricted to a NNWeSSE trending, elongated trough, which is deeply incised into unconsolidated lignite-bearing Palaeogene deposits. The geometry of this erosional structure points to a tunnel valley origin that was incised below the Elsterian ice sheet. The basal tunnel valley fill consists of cross-stratified pebbly sand and gravel overlain by till. After deglaciation the tunnel valley remained underfilled and acted as a depocentre for interglacial deposition. During the subsequent Holsteinian interglacial (MIS 9) a lake formed within this depocentre and lacustrine sediments accumulated. This interglacial succession consists of peat, organic-rich silt and fine-grained sand interpreted as lake-bottom and deltaic sediments fed by surface runoff shed from the Elm ridge. The lacustrine deposition was controlled by repeated lake-level fluctuations in the range of 1e6 m leading to the formation of laterally stacked delta systems. These lake-level changes were probably triggered by climate, causing variations of precipitation and surface runoff. During the late Saalian glaciation the remnant tunnel valley was completely filled with meltwater deposits. The sedimentary facies and depositional architecture point to a shallow-water delta. Subsequently the meltwater deposits were overlain by till. The deposition of the Middle Pleistocene sediments within an Elsterian tunnel valley explains the unique preservation of the sedimentary succession of Schöningen. The long-lived interglacial lake provided an attractive site for animals and early humans ambushing them. Artefacts mainly became embedded on the delta plain, which rapidly was transgressed during lake-level rise and artefacts were thus preserved.
Suitable host rocks for a repository for high-level radioactive waste (HLW) in Germany include no... more Suitable host rocks for a repository for high-level radioactive waste (HLW) in Germany include not only clay and crystalline rocks but also rock salt formations in so-called flat and steep bedding (StandAG, 2017). Favourable repository relevant properties of rock salt are, e.g. the high heat conductivity, low porosity and permeability, and its viscoplastic deformation behaviour. Thicker salt deposits can be attributed to the formation of approx. 700 salt structures that have formed under various geological conditions in the North German Basin (NGB) over the last 250 million years. According to their shape and genesis, salt structures are classified as salt pillows (considered as flat bedding) or salt diapirs (steep bedding). Out of a total of 74 sub-areas in rock salt, 60 sub-areas in salt diapirs consisting of Permian evaporates were identified within the first phase of the German site selection procedure (BGE, 2020). At the current stage of the site selection process, a conservative approach has been adopted and the internal structure of the salt structures have not yet been taken into account for further classification of the identified subareas. However, the interior of the salt structures not only consists of rock salt but also of varying proportions of clay, carbonate and anhydrite rocks, as well as potassium salts formed by progressive evaporation of marine brines. Multi-phase salt tectonics has led to the folding of these differently composed layers and to complex internal structures. Therefore, detailed knowledge of the salt structure compositions is necessary to identify suitable rock salt areas for the designation of the containment providing rock zone. As a result of decades of research through extensive salt and potash mining, cavern storage and exploration for final waste disposal, Permian salt rocks represent a well-studied host rock in Germany. The use of different exploration methods and multidisciplinary data evaluation have led to a comprehensive understanding of the internal composition of some well-studied salt structures. Systematic studies have shown that several factors have influenced the formation of salt structures as well as their external shapes, sizes, and spatial distribution (e.g., Pollok et al., 2020). Furthermore, the amount and distribution of suitable host rocks varies greatly in different salt structures and is closely related to their internal structure. Since the interior of salt structures has not been considered in the site selection process so far, a classification of salt structures (or sub-areas) into certain types with varying internal composition and complexity is presented. By examining their lithofacial composition, genesis, and structural geological position within the basin, it is possible to narrow down these types to specific areas in the NGB. Without the acquisition of additional exploration data in this phase of the site selection process, this salt structure classification provides important data for the legally demanded assessment of the overall favourable geological situation. Kurzfassung. Geeignete Wirtsgesteine für ein Endlager für hochradioaktive Abfälle (HAW) in Deutschland sind neben Ton-und Kristallingesteinen auch Steinsalzformationen in sogenannter flacher und steiler Lagerung (StandAG, 2017). Günstige endlagerrelevante Eigenschaften von Steinsalz sind z. B. die hohe Wärmeleitfähigkeit, die geringe Porosität und Permeabilität sowie sein viskoplastisches Verformungsverhalten. Mächtigere
This study presents a synthesis of the geomorphology, facies variability and depositional archite... more This study presents a synthesis of the geomorphology, facies variability and depositional architecture of ice-marginal deltas affected by rapid lake-level change. The integration of digital elevation models, outcrop, borehole, groundpenetrating radar and high-resolution shear-wave seismic data allows for a comprehensive analysis of these delta systems and provides information about the distinct types of deltaic facies and geometries generated under different lake-level trends. The exposed delta sediments record mainly the phase of maximum lake level and subsequent lake drainage. The stair-stepped profiles of the delta systems reflect the progressive basinward lobe deposition during forced regression when the lakes successively drained. Depending on the rate and magnitude of lake-level fall, fanshaped, lobate or more digitate tongue-like delta morphologies developed. Deposits of the stair-stepped transgressive delta bodies are buried, downlapped and onlapped by the younger forced regressive deposits. The delta styles comprise both Gilbert-type deltas and shoal-water deltas. The sedimentary facies of the steep Gilberttype delta foresets include a wide range of gravity-flow deposits. Delta deposits of the forced-regressive phase are commonly dominated by coarse-grained debrisflow deposits, indicating strong upslope erosion and cannibalization of older delta deposits. Deposits of supercritical turbidity currents are particularly common in sand-rich Gilbert-type deltas that formed during slow rises in lake level and during highstands. Foreset beds consist typically of laterally and vertically stacked deposits of antidunes and cyclic steps. The trigger mechanisms for these supercritical turbidity currents were both hyperpycnal meltwater flows and slope-failure events. Shoal-water deltas formed at low water depths during both low rates of lake-level rise and forced regression. Deposition occurred from tractional flows. Transgressive mouthbars form laterally extensive sand-rich delta bodies with a digitate, multi-tongue morphology. In contrast, forced regressive gravelly shoal-water deltas show a high dispersion of flow directions and form laterally overlapping delta lobes. Deformation structures in the forced-regressive ice-marginal deltas are mainly extensional features, including normal faults, small graben or half-graben structures and shear-deformation bands, which are related to gravitational delta tectonics, postglacial faulting during glacial-isostatic adjustment, and crestal collapse above salt domes. A neotectonic component cannot be ruled out in some cases.
In the last decades, salt-withdrawal basins achieved much attention due to their significant hydr... more In the last decades, salt-withdrawal basins achieved much attention due to their significant hydrocarbon potential like in the Gulf of Mexico, along the Brazilian passive margin and in northern Germany. The Helmstedt-Staßfurt salt wall and the related Schöningen rim syncline are an ideal natural laboratory to study the evolution of salt-withdrawal basins in detail. An excellent data set of 358 wells allows a detailed assessment of the basin-fill architecture. The aim was to expand on the classical cross-section based rim syncline analysis by the use of 3D models and basin simulations. The Helmstedt-Staßfurt salt wall is 70 km long, 6-8 km wide and one of the most important diapiric structures in northern Germany, based on the economically significant lignite-bearing rim synclines. The analysed Schöningen rim syncline, located on the southwestern side of the Helmstedt-Staßfurt structure, is 8 km long and 3 km wide. The basin-fill is up to 366 m thick and contains 13 major lignite sea...
Durch gezielte Aussolung von Salzgesteinen wurden bislang mehr als 300 Speicherkavernen in deutsc... more Durch gezielte Aussolung von Salzgesteinen wurden bislang mehr als 300 Speicherkavernen in deutschen Salzstrukturen errichtet. Sie dienen vor allem zur saisonalen Speicherung von Erdgas oder zur Lagerung strategischer Ölreserven. Im Rahmen des beschleunigten Übergangs auf fluktuierende erneuerbare Energieträger stellt sich die Frage der dezentralen großtechnischen Speicherung elektrischer Energie. Eine wichtige Rolle spielen Energiespeicherkraftwerke, die aus überschüssigem Strom Druckluft oder Wasserstoff erzeugen und in geeigneten Poren- bzw. Hohlräumen speichern. Eine großvolumige Speicherung dieser Medien kann nur behälterlos im geologischen Untergrund erfolgen. Aufgrund hoher Flexibilität in der Fahrweise, der mechanischen Stabilität sowie extrem geringer Reaktionsneigung mit dem Speichergut, stellen Salzkavernen die bevorzugte Speicheroption dar. 697 Salzstrukturen (Salzkissen, Salzstöcke oder Salzmauern) existieren im Norddeutschen Becken, das neben dem norddeutschen Festland...
This work reports on the use of a geological 3D model to reconstruct the development of salt stru... more This work reports on the use of a geological 3D model to reconstruct the development of salt structures. The study area is located in the south-eastern part of the North German Basin, in the State of Brandenburg. Notable structural features in the region are the salt domes Blankensee, Sperenberg and Paplitz, which are limited by the basement faults Cottbus-Störung and Lausitz-Störung (Kopp et.al. 2010). A third fault in this region is discussed by Krull (1991) and could be the extension of the Lausitzer Hauptabbruch. The salt structure Sperenberg located in the centre of the three domes, is limited by this supra-saline fault on the NE-flank. All faults show the same NW-SE striking orientation. Based on the horizons of the geological 3D model of the State of Brandenburg, and on integrated seismic and borehole data sets, it is possible to reconstruct the evolution of the three salt domes. Thickness variations of the rim synclines along the flanks of the three salt domes are used to de...
Im Rahmen des politisch forcierten Übergangs auf regenerative Energien stellt sich die Frage der ... more Im Rahmen des politisch forcierten Übergangs auf regenerative Energien stellt sich die Frage der großtechnischen Speicherung elektrischer Energie. Energiespeichern kommt zukünftig eine wichtige Rolle zu, da sich mit ihnen Schwankungen fluktuierender Energieträger ausgleichen lassen. Bei Bedarf können sie kurzfristig überschüssigen Strom, umgewandelt in Druckluft (CAES) oder Wasserstoff (H2), zwischenspeichern. Eine großvolumige Speicherung dieser Medien kann dabei nur im geologischen Untergrund erfolgen. Dabei stellen Salzkavernen aufgrund ihrer gebirgsmechanischen Stabilität, ihrer flexiblen Fahrweise sowie ihrer geringen Reaktionsneigung gegenüber dem Speichergut die bevorzugte Speicheroption dar. Für eine Bewertung verschiedener Salzstrukturen hinsichtlich ihrer Eignung für den Kavernenbau sowie eine fundierte Abschätzung, welche Energiemengen überhaupt im norddeutschen Untergrund speicherbar sind, mangelt es bisher an geeigneten Grundlagen. Diese Kenntnislücken werden mit dem Pr...
Suitable host rocks for a repository for high-level radioactive waste (HLW) in Germany include no... more Suitable host rocks for a repository for high-level radioactive waste (HLW) in Germany include not only clay and crystalline rocks but also rock salt formations in so-called flat and steep bedding (StandAG, 2017). Favourable repository relevant properties of rock salt are, e.g. the high heat conductivity, low porosity and permeability, and its viscoplastic deformation behaviour. Thicker salt deposits can be attributed to the formation of approx. 700 salt structures that have formed under various geological conditions in the North German Basin (NGB) over the last 250 million years. According to their shape and genesis, salt structures are classified as salt pillows (considered as flat bedding) or salt diapirs (steep bedding). Out of a total of 74 sub-areas in rock salt, 60 sub-areas in salt diapirs consisting of Permian evaporates were identified within the first phase of the German site selection procedure (BGE, 2020). At the current stage of the site selection process, a conservative approach has been adopted and the internal structure of the salt structures have not yet been taken into account for further classification of the identified subareas. However, the interior of the salt structures not only consists of rock salt but also of varying proportions of clay, carbonate and anhydrite rocks, as well as potassium salts formed by progressive evaporation of marine brines. Multi-phase salt tectonics has led to the folding of these differently composed layers and to complex internal structures. Therefore, detailed knowledge of the salt structure compositions is necessary to identify suitable rock salt areas for the designation of the containment providing rock zone. As a result of decades of research through extensive salt and potash mining, cavern storage and exploration for final waste disposal, Permian salt rocks represent a well-studied host rock in Germany. The use of different exploration methods and multidisciplinary data evaluation have led to a comprehensive understanding of the internal composition of some well-studied salt structures. Systematic studies have shown that several factors have influenced the formation of salt structures as well as their external shapes, sizes, and spatial distribution (e.g., Pollok et al., 2020). Furthermore, the amount and distribution of suitable host rocks varies greatly in different salt structures and is closely related to their internal structure. Since the interior of salt structures has not been considered in the site selection process so far, a classification of salt structures (or sub-areas) into certain types with varying internal composition and complexity is presented. By examining their lithofacial composition, genesis, and structural geological position within the basin, it is possible to narrow down these types to specific areas in the NGB. Without the acquisition of additional exploration data in this phase of the site selection process, this salt structure classification provides important data for the legally demanded assessment of the overall favourable geological situation. Kurzfassung. Geeignete Wirtsgesteine für ein Endlager für hochradioaktive Abfälle (HAW) in Deutschland sind neben Ton-und Kristallingesteinen auch Steinsalzformationen in sogenannter flacher und steiler Lagerung (StandAG, 2017). Günstige endlagerrelevante Eigenschaften von Steinsalz sind z. B. die hohe Wärmeleitfähigkeit, die geringe Porosität und Permeabilität sowie sein viskoplastisches Verformungsverhalten. Mächtigere
With Germany’s progressive energy revolution and its transition to fluctuating renewable energy s... more With Germany’s progressive energy revolution and its transition to fluctuating renewable energy sources large scale energy storages will be required. Storage power plants may play an important role for storing excess wind or solar energy converted to compressed air (CAES) or hydrogen. However, large volumes can only be accommodated in the geological subsurface. Because of its thermo-mechanical stability, its low tendency to react chemically with the stored medium and its flexible operation modes, salt caverns represent the preferred storage option. The focus of the InSpEE project is to provide basic geological and geotechnical data, to compile criteria for the establishment of salt caverns as well as to estimate the total renewable energy storage potential of salt structures in the North German Basin. In this collaborative project, existing expertise in salt geology, rock mechanics and cavern design principles are brought together by the Federal Institute for Geosciences and Natural Resources (BGR), Leibniz University of Hanover – Institute of Geotechnical Engineering/Department of Underground Construction (IGtH), and KBB Underground Technologies GmbH. The project’s results are integrated into a publicly accessible geo information system called “Salt”. Within this paper we present an overview of salt structures in the North German Basin and their internal compositions.
Underground storage in salt structures for compressed air or hydrogen are one of the few options ... more Underground storage in salt structures for compressed air or hydrogen are one of the few options for storing renewable energy in grid scale. However, there are only insufficiently substantiated estimates of the total potential. Therefore the objectives of the InSpEE project are the development and deployment of design principles and basic geological/geotechnical data and of site selection criteria for the establishment of salt caverns as well as the estimation of the renewable energy storage potentials of the salt structures in the North German Basin. Cooperating project partners bringing in their expertise in the areas of salt geology, rock mechanics and planning and construction of salt caverns. Thermo–mechanically based assessment criteria will be applied for the site characterization and an algorithm of the estimation of the possible storage potential will be developed. Finally, a publicly accessible “Salt information system” will be provided and the estimation storage potential for caverns in NW-Germany shall be addressed. Within this paper the rock mechanical design for CAES and H2 storage in salt caverns under consideration of thermo-mechanical coupled calculations will be presented as well as the methodology and the evaluation of the storage capacity for renewable energies.
The Federal Company for Radioactive Waste Disposal (BGE), the implementer of Germany's site selec... more The Federal Company for Radioactive Waste Disposal (BGE), the implementer of Germany's site selection procedure to identify a site suitable to safely dispose of its high-level nuclear waste, recently proposed a timeline suggesting the period between 2046 and 2068 as potential time slot for the final site decision (BGE, 2022). Thus, the decision is expected to be made substantially later than envisaged by the Site Selection Act, which states that one should aim for 2031 (StandAG, 2017). The BGE document not only details the timeline resulting in a site decision by mid-century but also outlines an alternative exploration approach inspired by the Swiss site selection procedure, which-if pursued-would enable substantial time gains. The core of this approach is a paradigm shift from exploration programs designed to acquire all data legally required for the safety analyses to data acquisition explicitly aiming at a site comparison during the respective exploration phase. Consequently, full-scale exploration would only be performed for those siting regions having passed the comparison. This contribution aims to detail and discuss this approach more thoroughly, based on the BGR's experience regarding the exploration of the subsurface. It focuses on the geoscientific aspects of this approach, while neglecting others such as the legal and administrative challenges. Owing to the basic idea of this alternative exploration approach, first a set of parameters suitable to differentiate potentially "better-suited" siting regions from "worsesuited" ones has to be identified. There are two main requirements for this set of parameters, namely the (i) general acceptance by the scientific community and (ii) capability to account for the specific characteristics of the individual host rock types while (still) ensuring the comparability of different rock types.
With Germany’s progressive energy revolution and its transition to fluctuating renewable energy s... more With Germany’s progressive energy revolution and its transition to fluctuating renewable energy sources large scale energy storages will be required. Storage power plants may play an important role for storing excess wind or solar energy converted to compressed air (CAES) or hydrogen. However, large volumes can only be accommodated in the geological subsurface. Because of its thermo-mechanical stability, its low tendency to react chemically with the stored medium and its flexible operation modes, salt caverns represent the preferred storage option. The focus of the InSpEE project is to provide basic geological and geotechnical data, to compile criteria for the establishment of salt caverns as well as to estimate the total renewable energy storage potential of salt structures in the North German Basin. In this collaborative project, existing expertise in salt geology, rock mechanics and cavern design principles are brought together by the Federal Institute for Geosciences and Natural Resources (BGR), Leibniz University of Hanover – Institute of Geotechnical Engineering/Department of Underground Construction (IGtH), and KBB Underground Technologies GmbH. The project’s results are integrated into a publicly accessible geo information system called “Salt”. Within this paper we present an overview of salt structures in the North German Basin and their internal compositions.
Underground storage in salt structures for compressed air or hydrogen are one of the few options ... more Underground storage in salt structures for compressed air or hydrogen are one of the few options for storing renewable energy in grid scale. However, there are only insufficiently substantiated estimates of the total potential. Therefore the objectives of the InSpEE project are the development and deployment of design principles and basic geological/geotechnical data and of site selection criteria for the establishment of salt caverns as well as the estimation of the renewable energy storage potentials of the salt structures in the North German Basin. Cooperating project partners bringing in their expertise in the areas of salt geology, rock mechanics and planning and construction of salt caverns. Thermo–mechanically based assessment criteria will be applied for the site characterization and an algorithm of the estimation of the possible storage potential will be developed. Finally, a publicly accessible “Salt information system” will be provided and the estimation storage potential for caverns in NW-Germany shall be addressed. Within this paper the rock mechanical design for CAES and H2 storage in salt caverns under consideration of thermo-mechanical coupled calculations will be presented as well as the methodology and the evaluation of the storage capacity for renewable energies.
The radioactive waste in the former Asse II salt mine has to be retrieved prior to the legally de... more The radioactive waste in the former Asse II salt mine has to be retrieved prior to the legally demanded decommissioning. In this context, the construction of a new mine and shaft is necessary, whereby detailed geological information about the salt structure is indispensable. Knowledge of the evaporite sequence, the internal composition, and the external shape of the Asse salt structure has been significantly enhanced by drill core investigations, borehole measurements, ground penetrating radar, and a new 3D seismic survey in recent years. The combined results indicate a highly complex internal structure with intensely folded Zechstein layers, contradicting earlier geological assumptions about this part of the salt structure. Furthermore, the strong tectonic influence during salt structure development is evidenced by complex structures in the cap rock and overburden, and by the formation of a salt wing on the steep southern flank. Additionally, a considerable narrowing of the salt structure to the southeast reduces the available space for the new mine. Our research shows that planning of waste repositories in complex salt structures has to be based on reliable, site-specific geoscientific data sets to reduce the risk of complications in the construction phase.
The site selection procedure for a high-level radioactive waste repository in Germany is based on... more The site selection procedure for a high-level radioactive waste repository in Germany is based on the Repository Site Selection Act (StandAG, 2017), which comprises three phases. In phase 2, the Federal Company for Radioactive Waste Disposal (BGE) will conduct surface exploration. Based on the exploratory findings, the further developed preliminary safety analyses, the common requirements and criteria, and socioeconomic potential analyses will be applied feeding into proposed sites for underground exploration. Commissioned by the BGE, the Federal Institute for Geosciences and Natural Resources (BGR) contributes to this procedure with the projects "GeoMePS" and "ZuBeMErk", which compile and assess geoscientific and geophysical methods and programs for surface exploration. Their common goal is to develop recommendations for surface exploration of siting regions. For this purpose, the BGR has developed a systematic approach that includes (1) deducing 186 exploration targets (Kneuker, 2020) based on the requirements defined by StandAG, (2) compilation of geoscientific and geophysical exploration methods in a database structure, and (3) analysis of case studies of national and international exploration programs for high-level radioactive waste disposal. During step (2) the BGR developed the database "GeM-DB" which utilizes MS SQL Server 2017 and PHP scripts for a browser-based interface (Beilecke, 2021). Both lead to a highly customizable, user-friendly database enabling further adaptations, expansions and analyses of the contents. Merging the knowledge of about 100 BGR experts, the database currently comprises approx. 140 geoscientific and geophysical exploration methods, including basic information and essential metadata to evaluate the general applicability of the methods for surface exploration of the three defined host rocks (crystalline rock, claystone, rock salt). Additionally, the methods are rated according to their suitability for the previously defined exploration targets. An example for a method selection, which is suitable to target fault zones (exclusion criterion 2, StandAG) is given in Fig. 1. In step (3) the BGR screens national and international waste disposal programs exploring for crystalline rock, claystone, and rock salt and feeds the obtained information back into "GeM-DB". The entire systematic approach of the projects "GeoMePS" and "ZuBeMErk" aims to develop recommendations for a non-destructive and minimally invasive surface exploration program of siting regions in Germany, regarding the lithological, structural, mechanical, and hydrogeological characterization of the different host rock formations. Kurzfassung. Das Standortauswahlverfahren für ein Endlager für hochradioaktive Abfälle in Deutschland basiert auf dem Standortauswahlgesetz (StandAG, 2017), das drei Phasen umfasst. In Phase 2 wird die Bundesgesellschaft für Endlagerung (BGE) mit der übertägigen Erkundung beginnen. Auf der Grundlage der Untersuchungsergebnisse werden die weiterentwickelten vorläufigen Sicherheitsanalysen, die allgemeinen Anforderungen und Kriterien sowie sozioökonomische Potenzialanalysen angewandt, die in die Vorschläge von Standorten einfließen werden, die für die untertägige Erkundung geeignet sind. Im Auftrag der BGE trägt die Bundesanstalt für Geowissenschaften und Rohstoffe (BGR) zu diesem Verfahren mit den Projekten "GeoMePS" und "ZuBeMErk" bei, in denen geowissenschaftliche und geophysikalische Methoden und Programme zur übertägigen Erkundung zusammengetragen und bewertet werden. Ihr gemeinsames Ziel besteht in der Entwicklung von Empfehlungen für die übertägige Erkundung von Stand-Published by Copernicus Publications on behalf of the Federal Office for the Safety of Nuclear Waste Management (BASE).
The radioactive waste in the former Asse II salt mine has to be retrieved prior to the legally de... more The radioactive waste in the former Asse II salt mine has to be retrieved prior to the legally demanded decommissioning. In this context, the construction of a new mine and shaft is necessary, whereby detailed geological information about the salt structure is indispensable. Knowledge of the evaporite sequence, the internal composition, and the external shape of the Asse salt structure has been significantly enhanced by drill core investigations, borehole measurements, ground penetrating radar, and a new 3D seismic survey in recent years. The combined results indicate a highly complex internal structure with intensely folded Zechstein layers, contradicting earlier geological assumptions about this part of the salt structure. Furthermore, the strong tectonic influence during salt structure development is evidenced by complex structures in the cap rock and overburden, and by the formation of a salt wing on the steep southern flank. Additionally, a considerable narrowing of the salt structure to the southeast reduces the available space for the new mine. Our research shows that planning of waste repositories in complex salt structures has to be based on reliable, site-specific geoscientific data sets to reduce the risk of complications in the construction phase.
74th EAGE Conference and Exhibition incorporating EUROPEC 2012, 2012
Dedicated Glaciations In this paper we will document the stratigraphic evolution, internal facies... more Dedicated Glaciations In this paper we will document the stratigraphic evolution, internal facies architecture and geomorphology of regressive glacigenic deltas, controlled by rapid high-amplitude base-level change. These systems are excellent field example to test the effect of high-amplitude base-level change on glacigenic delta systems, because subsidence, compaction, wave or tides did not play a major role. A large data set, including outcrop data, borehole data and high-resolution shear-wave seismic sections can resolve architectural elements in the range of metres and bridge the common gap between outcrop and standard industrial compression wave seismic data. The objective of this work is to provide a synthesis of the stratigraphic architecture of regressive deltas, giving new insights into the controls on delta building and erosion processes. The emphasis is placed on the sedimentary facies associations, the correlation of seismic facies with boreholes and outcrops and the analysis of the larger scale stacking pattern of architectural elements. A new depositional model summarizing facies features, depositional processes and architectures is proposed that may add to the sequence stratigraphic interpretation of steep glacigenic delta systems, controlled by rapid base-level change.
The Pleistocene deposits of Schöningen represent an outstanding geological and archaeological arc... more The Pleistocene deposits of Schöningen represent an outstanding geological and archaeological archive, where an up to 45 m thick Middle to Late Pleistocene succession has been preserved and unique artefacts from the Lower Palaeolithic have been discovered. The preservation of such a thick and complete glacial/ interglacial succession is very rare in the geological record and requires a specific depositional setting. We will present a new depositional model for the Pleistocene succession of Schöningen, integrating outcrop data, borehole data and high-resolution shear wave seismics. A total of four outcrop sections and 744 borehole logs were examined to document the complex facies architecture. All collected sedimentological and geophysical data sets were integrated into a high-resolution 3D geological model (GOCAD Ò) for reconstructing the spatial distribution of facies associations and the large-scale depositional architecture. The spatial distribution of the artefacts will be discussed with respect to the depositional environment. The Elsterian and Holsteinian deposits are restricted to a NNWeSSE trending, elongated trough, which is deeply incised into unconsolidated lignite-bearing Palaeogene deposits. The geometry of this erosional structure points to a tunnel valley origin that was incised below the Elsterian ice sheet. The basal tunnel valley fill consists of cross-stratified pebbly sand and gravel overlain by till. After deglaciation the tunnel valley remained underfilled and acted as a depocentre for interglacial deposition. During the subsequent Holsteinian interglacial (MIS 9) a lake formed within this depocentre and lacustrine sediments accumulated. This interglacial succession consists of peat, organic-rich silt and fine-grained sand interpreted as lake-bottom and deltaic sediments fed by surface runoff shed from the Elm ridge. The lacustrine deposition was controlled by repeated lake-level fluctuations in the range of 1e6 m leading to the formation of laterally stacked delta systems. These lake-level changes were probably triggered by climate, causing variations of precipitation and surface runoff. During the late Saalian glaciation the remnant tunnel valley was completely filled with meltwater deposits. The sedimentary facies and depositional architecture point to a shallow-water delta. Subsequently the meltwater deposits were overlain by till. The deposition of the Middle Pleistocene sediments within an Elsterian tunnel valley explains the unique preservation of the sedimentary succession of Schöningen. The long-lived interglacial lake provided an attractive site for animals and early humans ambushing them. Artefacts mainly became embedded on the delta plain, which rapidly was transgressed during lake-level rise and artefacts were thus preserved.
Suitable host rocks for a repository for high-level radioactive waste (HLW) in Germany include no... more Suitable host rocks for a repository for high-level radioactive waste (HLW) in Germany include not only clay and crystalline rocks but also rock salt formations in so-called flat and steep bedding (StandAG, 2017). Favourable repository relevant properties of rock salt are, e.g. the high heat conductivity, low porosity and permeability, and its viscoplastic deformation behaviour. Thicker salt deposits can be attributed to the formation of approx. 700 salt structures that have formed under various geological conditions in the North German Basin (NGB) over the last 250 million years. According to their shape and genesis, salt structures are classified as salt pillows (considered as flat bedding) or salt diapirs (steep bedding). Out of a total of 74 sub-areas in rock salt, 60 sub-areas in salt diapirs consisting of Permian evaporates were identified within the first phase of the German site selection procedure (BGE, 2020). At the current stage of the site selection process, a conservative approach has been adopted and the internal structure of the salt structures have not yet been taken into account for further classification of the identified subareas. However, the interior of the salt structures not only consists of rock salt but also of varying proportions of clay, carbonate and anhydrite rocks, as well as potassium salts formed by progressive evaporation of marine brines. Multi-phase salt tectonics has led to the folding of these differently composed layers and to complex internal structures. Therefore, detailed knowledge of the salt structure compositions is necessary to identify suitable rock salt areas for the designation of the containment providing rock zone. As a result of decades of research through extensive salt and potash mining, cavern storage and exploration for final waste disposal, Permian salt rocks represent a well-studied host rock in Germany. The use of different exploration methods and multidisciplinary data evaluation have led to a comprehensive understanding of the internal composition of some well-studied salt structures. Systematic studies have shown that several factors have influenced the formation of salt structures as well as their external shapes, sizes, and spatial distribution (e.g., Pollok et al., 2020). Furthermore, the amount and distribution of suitable host rocks varies greatly in different salt structures and is closely related to their internal structure. Since the interior of salt structures has not been considered in the site selection process so far, a classification of salt structures (or sub-areas) into certain types with varying internal composition and complexity is presented. By examining their lithofacial composition, genesis, and structural geological position within the basin, it is possible to narrow down these types to specific areas in the NGB. Without the acquisition of additional exploration data in this phase of the site selection process, this salt structure classification provides important data for the legally demanded assessment of the overall favourable geological situation. Kurzfassung. Geeignete Wirtsgesteine für ein Endlager für hochradioaktive Abfälle (HAW) in Deutschland sind neben Ton-und Kristallingesteinen auch Steinsalzformationen in sogenannter flacher und steiler Lagerung (StandAG, 2017). Günstige endlagerrelevante Eigenschaften von Steinsalz sind z. B. die hohe Wärmeleitfähigkeit, die geringe Porosität und Permeabilität sowie sein viskoplastisches Verformungsverhalten. Mächtigere
This study presents a synthesis of the geomorphology, facies variability and depositional archite... more This study presents a synthesis of the geomorphology, facies variability and depositional architecture of ice-marginal deltas affected by rapid lake-level change. The integration of digital elevation models, outcrop, borehole, groundpenetrating radar and high-resolution shear-wave seismic data allows for a comprehensive analysis of these delta systems and provides information about the distinct types of deltaic facies and geometries generated under different lake-level trends. The exposed delta sediments record mainly the phase of maximum lake level and subsequent lake drainage. The stair-stepped profiles of the delta systems reflect the progressive basinward lobe deposition during forced regression when the lakes successively drained. Depending on the rate and magnitude of lake-level fall, fanshaped, lobate or more digitate tongue-like delta morphologies developed. Deposits of the stair-stepped transgressive delta bodies are buried, downlapped and onlapped by the younger forced regressive deposits. The delta styles comprise both Gilbert-type deltas and shoal-water deltas. The sedimentary facies of the steep Gilberttype delta foresets include a wide range of gravity-flow deposits. Delta deposits of the forced-regressive phase are commonly dominated by coarse-grained debrisflow deposits, indicating strong upslope erosion and cannibalization of older delta deposits. Deposits of supercritical turbidity currents are particularly common in sand-rich Gilbert-type deltas that formed during slow rises in lake level and during highstands. Foreset beds consist typically of laterally and vertically stacked deposits of antidunes and cyclic steps. The trigger mechanisms for these supercritical turbidity currents were both hyperpycnal meltwater flows and slope-failure events. Shoal-water deltas formed at low water depths during both low rates of lake-level rise and forced regression. Deposition occurred from tractional flows. Transgressive mouthbars form laterally extensive sand-rich delta bodies with a digitate, multi-tongue morphology. In contrast, forced regressive gravelly shoal-water deltas show a high dispersion of flow directions and form laterally overlapping delta lobes. Deformation structures in the forced-regressive ice-marginal deltas are mainly extensional features, including normal faults, small graben or half-graben structures and shear-deformation bands, which are related to gravitational delta tectonics, postglacial faulting during glacial-isostatic adjustment, and crestal collapse above salt domes. A neotectonic component cannot be ruled out in some cases.
In the last decades, salt-withdrawal basins achieved much attention due to their significant hydr... more In the last decades, salt-withdrawal basins achieved much attention due to their significant hydrocarbon potential like in the Gulf of Mexico, along the Brazilian passive margin and in northern Germany. The Helmstedt-Staßfurt salt wall and the related Schöningen rim syncline are an ideal natural laboratory to study the evolution of salt-withdrawal basins in detail. An excellent data set of 358 wells allows a detailed assessment of the basin-fill architecture. The aim was to expand on the classical cross-section based rim syncline analysis by the use of 3D models and basin simulations. The Helmstedt-Staßfurt salt wall is 70 km long, 6-8 km wide and one of the most important diapiric structures in northern Germany, based on the economically significant lignite-bearing rim synclines. The analysed Schöningen rim syncline, located on the southwestern side of the Helmstedt-Staßfurt structure, is 8 km long and 3 km wide. The basin-fill is up to 366 m thick and contains 13 major lignite sea...
Durch gezielte Aussolung von Salzgesteinen wurden bislang mehr als 300 Speicherkavernen in deutsc... more Durch gezielte Aussolung von Salzgesteinen wurden bislang mehr als 300 Speicherkavernen in deutschen Salzstrukturen errichtet. Sie dienen vor allem zur saisonalen Speicherung von Erdgas oder zur Lagerung strategischer Ölreserven. Im Rahmen des beschleunigten Übergangs auf fluktuierende erneuerbare Energieträger stellt sich die Frage der dezentralen großtechnischen Speicherung elektrischer Energie. Eine wichtige Rolle spielen Energiespeicherkraftwerke, die aus überschüssigem Strom Druckluft oder Wasserstoff erzeugen und in geeigneten Poren- bzw. Hohlräumen speichern. Eine großvolumige Speicherung dieser Medien kann nur behälterlos im geologischen Untergrund erfolgen. Aufgrund hoher Flexibilität in der Fahrweise, der mechanischen Stabilität sowie extrem geringer Reaktionsneigung mit dem Speichergut, stellen Salzkavernen die bevorzugte Speicheroption dar. 697 Salzstrukturen (Salzkissen, Salzstöcke oder Salzmauern) existieren im Norddeutschen Becken, das neben dem norddeutschen Festland...
This work reports on the use of a geological 3D model to reconstruct the development of salt stru... more This work reports on the use of a geological 3D model to reconstruct the development of salt structures. The study area is located in the south-eastern part of the North German Basin, in the State of Brandenburg. Notable structural features in the region are the salt domes Blankensee, Sperenberg and Paplitz, which are limited by the basement faults Cottbus-Störung and Lausitz-Störung (Kopp et.al. 2010). A third fault in this region is discussed by Krull (1991) and could be the extension of the Lausitzer Hauptabbruch. The salt structure Sperenberg located in the centre of the three domes, is limited by this supra-saline fault on the NE-flank. All faults show the same NW-SE striking orientation. Based on the horizons of the geological 3D model of the State of Brandenburg, and on integrated seismic and borehole data sets, it is possible to reconstruct the evolution of the three salt domes. Thickness variations of the rim synclines along the flanks of the three salt domes are used to de...
Im Rahmen des politisch forcierten Übergangs auf regenerative Energien stellt sich die Frage der ... more Im Rahmen des politisch forcierten Übergangs auf regenerative Energien stellt sich die Frage der großtechnischen Speicherung elektrischer Energie. Energiespeichern kommt zukünftig eine wichtige Rolle zu, da sich mit ihnen Schwankungen fluktuierender Energieträger ausgleichen lassen. Bei Bedarf können sie kurzfristig überschüssigen Strom, umgewandelt in Druckluft (CAES) oder Wasserstoff (H2), zwischenspeichern. Eine großvolumige Speicherung dieser Medien kann dabei nur im geologischen Untergrund erfolgen. Dabei stellen Salzkavernen aufgrund ihrer gebirgsmechanischen Stabilität, ihrer flexiblen Fahrweise sowie ihrer geringen Reaktionsneigung gegenüber dem Speichergut die bevorzugte Speicheroption dar. Für eine Bewertung verschiedener Salzstrukturen hinsichtlich ihrer Eignung für den Kavernenbau sowie eine fundierte Abschätzung, welche Energiemengen überhaupt im norddeutschen Untergrund speicherbar sind, mangelt es bisher an geeigneten Grundlagen. Diese Kenntnislücken werden mit dem Pr...
ABSTRACT Salt rim synclines contain important hydrocarbon and coal resources in central Europe. T... more ABSTRACT Salt rim synclines contain important hydrocarbon and coal resources in central Europe. The Schöningen salt rim syncline is filled with >300 m of Early to Middle Eocene unconsolidated clastics with interbedded lignitic coal seams that are mined at the surface. In this study, 357 lithologic logs are integrated with measured outcrop sections and paleo-botanical data to interpret the depositional environments and sequence stratigraphic framework of the rim syncline fill. As salt withdrew, it generated an elongate mini-basin that mimicked an incised valley. The sustained accommodation and slow broadening of the syncline affected the stratigraphic architecture and contributed to the preservation of coal units. The clastic units in the syncline filled in seven depositional stages: (1) tidally influenced fluvial estuarine channels; (2) mixed tide- and wave- dominated estuaries; (3) prograding wave dominate deltas; (4) transgressive shoreline deposits; (5) braided fluvial channels; (6) estuaries; and (7) prograding tide-dominated channels. The succession defines four 3rd order sequences and several higher order sequences that are possibly related to Milankovitch cycles. The higher order sequences are dominantly characterized by stacked transgressive cycles of thick, lowstand coals overlain by estuarine sands. The nearly continuous warm and wet Eocene climate was conducive to continuous peat production with a climatic overprint recorded in the mire type: ombrotrophic mires developed in wetter times and rheotrophic mires developed in relatively drier conditions pointing to the presence of orbitally controlled seasonality. Both mire types were impacted by the interplay of subsidence and base-level. The continuous dropping of the mires below base-level via subsidence protected the mires against erosion and may account for the absence of coals outside of the rim synclines in the region.
... Christian Brandes,* Lukas Pollok,* Carolin Schmidt,* Volker Wilde† and Jutta Winsemann* *Inst... more ... Christian Brandes,* Lukas Pollok,* Carolin Schmidt,* Volker Wilde† and Jutta Winsemann* *Institut fu¨r Geologie, Leibniz Universita¨t Hannover, Callinstr. ... The CEBS is bounded to the northeast by the Teisseyre-Tornquist Zone and Sorgenfrei-Tornquist Zone. ...
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