GLORIA

GEOMAR Library Ocean Research Information Access

X

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Online Resource
    Online Resource
    A multidisciplinary approach considering geochemical reorganization and internal structure of tailings impoundments for metal exploration
    Elsevier BV ; 2019
    In:  Applied Geochemistry Vol. 104 ( 2019-05), p. 51-59
    Details
    In: Applied Geochemistry, Elsevier BV, Vol. 104 ( 2019-05), p. 51-59
    Type of Medium: Online Resource
    ISSN: 0883-2927
    URL: Article
    DOI: 10.1016/j.apgeochem.2019.03.014
    Language: English
    Publisher: Elsevier BV
    Publication Date: 2019
    detail.hit.zdb_id: 1499242-5
    SSG: 13
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 2
    Online Resource
    Online Resource
    Development and characterization of glass matrix composites as porous coating film of a solid state reference electrode
    IMAPS - International Microelectronics Assembly and Packaging Society ; 2012
    In:  Additional Conferences (Device Packaging, HiTEC, HiTEN, and CICMT) Vol. 2012, No. CICMT ( 2012-09-01), p. 000200-000207
    Details
    In: Additional Conferences (Device Packaging, HiTEC, HiTEN, and CICMT), IMAPS - International Microelectronics Assembly and Packaging Society, Vol. 2012, No. CICMT ( 2012-09-01), p. 000200-000207
    Abstract: For protection against leaching of the electrolyte reservoir of a solid state reference electrode a porous covering film was prepared and characterized. The porous covering film is based on a glass matrix composite and fired at 400 °C according to the thick-film-based structure of the reference electrode. Based on stability investigations on low sintering glasses in the range of pH 1.68 to pH 9.18 and in various concentrated potassium chloride solutions, a suitable zinc borate glass was selected. Using this glass and Al2O3 or ZrO2 oxide powders, various glass matrix composites were prepared and their sintering behavior was investigated in dependence on the amount of crystalline fraction up to 45 vol%. The shrinkage was measured by heating microscopy of powder compacts of cylindrical shape. In addition composite films on ZrO2 substrates screen-printed and at 400 °C fired were characterized in terms of their porosity by means of micro structural analysis and electrochemical deposition of copper. According to these investigations, suitable composites were selected as porous covering materials for the reference electrode and were tested therefore. The electrochemical characterization showed that the solid-state reference electrodes with porous covering films have a very good performance compared to conventional reference electrodes.
    Type of Medium: Online Resource
    ISSN: 2380-4491
    URL: Article
    DOI: 10.4071/CICMT-2012-TP46
    Language: English
    Publisher: IMAPS - International Microelectronics Assembly and Packaging Society
    Publication Date: 2012
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 3
    Online Resource
    Online Resource
    Microstructure and composition of brittle faults in claystones of the Mont Terri rock laboratory (Switzerland): New data from petrographic studies, geophysical borehole logging and permeability tests
    Elsevier BV ; 2017
    In:  Engineering Geology Vol. 231 ( 2017-12), p. 139-156
    Details
    In: Engineering Geology, Elsevier BV, Vol. 231 ( 2017-12), p. 139-156
    Type of Medium: Online Resource
    ISSN: 0013-7952
    URL: Article
    DOI: 10.1016/j.enggeo.2017.10.016
    Language: English
    Publisher: Elsevier BV
    Publication Date: 2017
    detail.hit.zdb_id: 1500329-2
    SSG: 19,1
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 4
    Online Resource
    Online Resource
    From process to system understanding with multi-disciplinary investigation methods: set-up and first results of the CD-A experiment (Mont Terri rock laboratory)
    Copernicus GmbH ; 2021
    In:  Safety of Nuclear Waste Disposal Vol. 1 ( 2021-11-10), p. 79-81
    Details
    In: Safety of Nuclear Waste Disposal, Copernicus GmbH, Vol. 1 ( 2021-11-10), p. 79-81
    Abstract: Abstract. A potential repository site for high-level radioactive waste should ensure the highest possible safety level over a period of one million years. In addition to design issues, demonstrating the integrity of the barrier is essential as it ensures the long-term containment of radioactive waste. Therefore, a multi-disciplinary approach is necessary for the characterization of the surrounding rock and for the understanding of the occurring physical processes. For site selection, however, the understanding of the respective system is essential as well: Do fault zones exist in the relevant area? Are these active and relevant for interpreting system behavior? What is the role of the existing heterogeneities of the claystone and how do these site-dependent conditions influence the physical effects? To answer these questions, the site-selection procedure requires underground exploration, which includes geophysical and geological investigations on milli- to decameter scales. Their results serve as the basis for numerical modelling. This combined, multi-disciplinary interpretation requires extensive knowledge of the various methods, their capabilities, limitations, and areas of application. In the cyclic deformation (CD-A) experiment in the Mont Terri rock laboratory, the hydraulic–mechanical effects due to excavation and the climatic conditions within the rock laboratory are investigated in two niches in the Opalinus Clay. The twin niches differ mainly with regard to the relative humidity inside them, but are also characterized by different boundary conditions such as existing fault zones, the technical construction of the neighboring gallery, etc. In order to gain insights into the relevance of the individual influences, comparative studies are being carried out on both niches. The presented results provide a first insight into the initial experimental years of the CD-A long-term experiment and illustrate the benefits of multi-disciplinary investigations in terms of system understanding and the scale dependency of physical effects. Amongst other effects, the assessment of the impact of heterogeneities on the deformation behavior and the evolution of pore water pressure is very complex and benefits from geological interpretation and measurements of for example deformation, water content, and pore pressure. The numerical modeling allows statements about the interaction of different processes and thus enables an interpretation of the overall system, taking into account the knowledge gained by the multi-disciplinary investigation.
    Type of Medium: Online Resource
    ISSN: 2749-4802
    URL: Article
    URL: Article
    DOI: 10.5194/sand-1-79-2021
    DOI: 10.5194/sand-1-79-2021-supplement
    Language: English
    Publisher: Copernicus GmbH
    Publication Date: 2021
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 5
    Online Resource
    Online Resource
    Capturing the structural and compositional variability of Opalinus Clay: constraints from multidisciplinary investigations of Mont Terri drill cores (Switzerland)
    Springer Science and Business Media LLC ; 2021
    In:  Environmental Earth Sciences Vol. 80, No. 11 ( 2021-06)
    Details
    In: Environmental Earth Sciences, Springer Science and Business Media LLC, Vol. 80, No. 11 ( 2021-06)
    Abstract: Opalinus Clay is considered a potential host rock for radioactive waste disposal. The Jurassic claystone formation is composed of several facies and subfacies types, which are characterized by varying amounts of quartz, carbonates (cements and fossils) and clay minerals. To provide samples for ongoing experimental and numerical studies, a complete core section was drilled in the Mont Terri rock laboratory. The lithological and structural variability (including tectonic fault structures) from borehole BAD-2 was investigated using a multidisciplinary approach including high-resolution geoelectric in situ borehole measurements, mineralogical/geochemical and (micro)structural analyses. The lithological–compositional variability was captured by successfully applying a modified subfacies approach, which is independently confirmed by the geochemical data and ERT (Electrical Resistivity Tomography) measurements. The variability on the cm to dm scale perpendicular to bedding can be determined based on the mean resistivity and variation of amplitude. In particular, the facies transitions could be precisely located. The new results suggest that both shaly facies types form the homogenous part of the investigated section, whereas the sandy facies and especially the carbonate-rich sandy facies represent the more heterogeneous lithofacies types of the Opalinus Clay. The varying resistivity can be attributed to differences in clay mineral and carbonate content. Regarding the structural variability, brittle faults were observed with varying frequency throughout the investigated section. Most fault planes occur in the shaly facies types, some of them concentrate along heterogeneities on the subfacies scale. The striking reproducibility of the measurements and observations was confirmed by a comparison with boreholes drilled in parallel, indicating a rather low compositional–structural variability parallel to bedding. The applied multidisciplinary approach is well suited to depict the vertical and lateral variability of a claystone formation, allowing an assessment of the degree of homogeneity/heterogeneity based on the subfacies concept.
    Type of Medium: Online Resource
    ISSN: 1866-6280 , 1866-6299
    URL: Article
    DOI: 10.1007/s12665-021-09708-1
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2021
    detail.hit.zdb_id: 2493699-6
    SSG: 13
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 6
    Online Resource
    Online Resource
    Understanding the evolution of nuclear waste repositories by performing appropriate experiments – selected investigations at Mont Terri rock laboratory
    Copernicus GmbH ; 2019
    In:  Advances in Geosciences Vol. 49 ( 2019-10-30), p. 175-186
    Details
    In: Advances in Geosciences, Copernicus GmbH, Vol. 49 ( 2019-10-30), p. 175-186
    Abstract: Abstract. Any site selection process for a final repository for high-level and heat producing radioactive waste is a national challenge and has to take into account, among others, regional geological settings. In Germany, the site selection has to restart from zero, and all potential host rocks have to be considered equal, including argillaceous rocks. Therefore, the Federal Institute for Geosciences and Natural Resources (BGR) performs appropriate experiments in the Swiss Mont Terri rock laboratory, which is located in the Jurassic Opalinus Clay. In this paper, activities and results from actual and still ongoing experiments, with participation of BGR, are presented exemplarily. All experiments aim for a contribution to understand particular aspects regarding the behaviour of underground facilities, BGR's focus lies mainly on aspects of the early lifetime of a repository, namely the construction, post-closure transient, and partly post-closure equilibrium phases. It is obvious that for a full understanding of the evolution of a final repository, knowledge and experience of many different groups, their studies and results covering all aspects, have to be included. In this paper, we can only emphasise a few representative examples on geophysical and geotechnical in-situ site investigations, geotechnical mine-by monitoring, laboratory investigations, and modelling aspects. The combined interpretation of these results enhance interpretations and is a prerequisite for a comprehensive understanding of a repository.
    Type of Medium: Online Resource
    ISSN: 1680-7359
    URL: Article
    DOI: 10.5194/adgeo-49-175-2019
    Language: English
    Publisher: Copernicus GmbH
    Publication Date: 2019
    detail.hit.zdb_id: 2625759-2
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 7
    Online Resource
    Online Resource
    Formation of sequences of cemented layers and hardpans within sulfide-bearing mine tailings (mine district Freiberg, Germany)
    Elsevier BV ; 2007
    In:  Applied Geochemistry Vol. 22, No. 11 ( 2007-11), p. 2486-2508
    Details
    In: Applied Geochemistry, Elsevier BV, Vol. 22, No. 11 ( 2007-11), p. 2486-2508
    Type of Medium: Online Resource
    ISSN: 0883-2927
    URL: Article
    DOI: 10.1016/j.apgeochem.2007.07.002
    Language: English
    Publisher: Elsevier BV
    Publication Date: 2007
    detail.hit.zdb_id: 1499242-5
    SSG: 13
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 8
    Online Resource
    Online Resource
    Large-scale testing of a sandwich shaft-sealing system at the Mont Terri rock laboratory
    Copernicus GmbH ; 2021
    In:  Safety of Nuclear Waste Disposal Vol. 1 ( 2021-11-10), p. 133-135
    Details
    In: Safety of Nuclear Waste Disposal, Copernicus GmbH, Vol. 1 ( 2021-11-10), p. 133-135
    Abstract: Abstract. Shaft-sealing systems for nuclear waste repositories are constructed to limit fluid inflow from the adjacent rock during the early stage after closure of the repository and to delay the release of possibly contaminated fluids from the repository at later stages. Current German concepts of shaft seals contain the hydraulic sandwich sealing system as a component of the lower seal in host rock (Kudla and Herold, 2021). The KIT-developed sandwich sealing system consists of alternating sealing segments (DS) of bentonite and equipotential segments (ES) that are characterized by a high hydraulic conductivity. Within the ES, fluid is evenly distributed over the cross section of the seal. Water bypassing the seal via the excavation-damaged zone or penetrating the seal inhomogeneously is contained, and a more homogeneous hydration and swelling of the DS is obtained. The functionality of such a system was proven in laboratory and semi-technical-scale experiments (Schuhmann et al., 2009). After a joint international pre-project (Emmerich et al., 2019) dedicated to the planning of a large-scale in situ test that demonstrates the feasibility and effectiveness of the sandwich shaft-sealing system in interaction with the host rock, the large-scale experiment was launched at the Mont Terri rock laboratory in July 2019 with partners from Germany, Switzerland, Spain, UK, and Canada. It consists of two experimental shafts of 1.18 m diameter and 10–12.6 m depth, constructed using a core drilling technique with a custom-made drill rig in a new niche in the sandy facies of the Opalinus Clay. The seal in shaft 1 consists of four DS (calcigel) of 1 m thickness and five ES (fine-grained quartz sand), each 30 cm thick (Fig. 1). Shaft sinking began in August 2020 and was completed in November 2020. In the following months, the sealing system and instrumentation of shaft 1 were installed. The sealing system is saturated from a pressure chamber located at the shaft bottom via an inclined lateral feeding borehole. Hydration of the system started in May 2021. Shaft 2 will host a slightly modified system emplaced 1–1.5 years later, in order to integrate experience obtained during the early operation phase of shaft 1. In contrast to shaft 1, the excavation-damaged zone around shaft 2 will have had time to develop. The seals and the surrounding rock are intensely monitored. Measurements in the rock (geophysics, pore pressure, and total stress) were started between August 2019 and March 2020. Characterization of the excavation-damaged zone along the wall of shaft 1 was performed by geophysical and surface packer measurements prior to seal emplacement. Measurements inside the shaft comprise water content, relative humidity, and temperature, pore pressure, stress, and displacements. The in situ work is backed by laboratory testing and model simulation. Data and experience obtained to date will be presented. The sandwich experiment is funded by the German Federal Ministry for Economic Affairs and Energy under contract 02E11799.
    Type of Medium: Online Resource
    ISSN: 2749-4802
    URL: Article
    URL: Article
    DOI: 10.5194/sand-1-133-2021
    DOI: 10.5194/sand-1-133-2021-supplement
    Language: English
    Publisher: Copernicus GmbH
    Publication Date: 2021
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 9
    Online Resource
    Online Resource
    Hydration and response of an experimental Sandwich shaft-sealing system at the Mont Terri rock laboratory
    Copernicus GmbH ; 2023
    In:  Safety of Nuclear Waste Disposal Vol. 2 ( 2023-09-06), p. 175-176
    Details
    In: Safety of Nuclear Waste Disposal, Copernicus GmbH, Vol. 2 ( 2023-09-06), p. 175-176
    Abstract: Abstract. A necessary and important component for the closure of deep geological repositories (accessed by a shaft) is a shaft-sealing system that limits the fluid inflow from the adjacent rock to the repository in the early post-closure phase and delays the release of possibly contaminated fluids from the repository at a later stage. The Sandwich system developed at Karlsruhe Institute of Technology (Schuhmann et al., 2009) is a multicomponent barrier that can contribute to this sealing function and is considered as part of the German shaft-sealing concept (Kudla and Herold, 2021). Its functionality has been assessed in a large-scale in situ test (the SW-A experiment) carried out at the Mont Terri rock laboratory (MTRL) in cooperation with international partners as part of the Sandwich-HP project since July 2019. The in situ test was planned as part of an international pre-project (Emmerich et al., 2019) and is accompanied by a laboratory- and semi-technical-scale test program as well as by model simulations. The setup of the SW-A experiment comprises two shafts of 1.18 m diameter and 10–12.6 m depth in the Sandy Facies of the Opalinus Clay at MTRL. Each shaft contains a Sandwich seal as well as a hydration system in order to realize fluid inflow from the bottom (Fig. 1a). The implemented Sandwich system is characterized by an alternating arrangement of four low-permeability sealing segments (DS) made of bentonite and five equipotential segments (ES) made of fine-grained quartz sand with higher hydraulic conductivity. Fluid entering an ES is supposed to be evenly distributed over the cross section and, thus, the interface of the adjacent DS, leading to a homogeneous hydration and swelling of the DS. Water bypassing a DS and high hydraulic loads can be absorbed and distributed by the next ES. In the experiment, the sealing systems and the surrounding rock are intensely monitored (e.g., geophysics, water content, relative humidity and temperature, pore pressure, stress, and displacement) in order to investigate the saturation process and assess the interaction of the sealing system and the host rock. Hydration of the system in Shaft 1 started in May 2021, and the monitoring system showed a relatively fast saturation of the lowermost ES and DS and a water bypass in August 2021 (Fig. 1b); this was accompanied by slower saturation of the upper ES and DS, swelling of the DS and a pore pressure increase in the surrounding rock. Hydration of Shaft 2 started in May 2023. Data and experience obtained to date will be presented.
    Type of Medium: Online Resource
    ISSN: 2749-4802
    URL: Article
    DOI: 10.5194/sand-2-175-2023
    Language: English
    Publisher: Copernicus GmbH
    Publication Date: 2023
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...