6,086 results on '"Géologie"'
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2. Anthropozän
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Folkers, Andreas, Sonnberger, Marco, editor, Bleicher, Alena, editor, and Groß, Matthias, editor
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- 2024
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3. La réflexivité géologique des sciences modernes : De l’activité humaine dans la géologie (xixe – début xxe s.).
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de Jouvancourt, Pierre
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Copyright of Revue d'Histoire des Sciences is the property of Librairie Armand Colin and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2024
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4. State of the art of wear prediction in mechanised tunnelling.
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Stopp, Annika and Feinendegen, Martin
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TUNNEL design & construction , *ROCK music , *CUTTING tools , *FORECASTING , *SUBSOILS - Abstract
The wear of cutting tools in mechanised tunnelling is closely linked to the abrasiveness of the present subsoil. Therefore, most of the models used for wear prediction take an abrasiveness index into account. The most common index used for hard rock is the Cerchar Abrasiveness Index (CAI); whereas such a standard does not yet exist for soil. Both the literature research and the results of calculation examples presented in the article show that significantly more practical models are currently available for wear prediction in hard rock. One reason for this is that far more wear‐relevant influencing factors have to be quantified for soft ground. Another reason is that the scientific studies concerning this topic only started in the course of mechanised tunnelling. Since especially the calculations carried out for low‐abrasive rocks differ widely among the different models for tool life, further research is needed also for wear prediction in hard rock [ABSTRACT FROM AUTHOR]
- Published
- 2023
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5. 'Der sterbende Leichnam der Natur'. Geologische Provokationen bei Goethe, Novalis und Tieck
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Attanucci, Timothy, Borgards, Roland, Series Editor, Middelhoff, Frederike, Series Editor, Wernli, Martina, Series Editor, Boehm, Katharina, Advisory Editor, Grave, Johannes, Advisory Editor, Holm, Christiane, Advisory Editor, Hühn, Helmut, Advisory Editor, Lennartz, Norbert, Advisory Editor, Müller, Gesine, Advisory Editor, Müller-Wille, Klaus, Advisory Editor, Schmitz-Emans, Monika, Advisory Editor, and Thums, Barbara, editor
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- 2023
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6. THE CONTRIBUTION OF GEOPHYSICS TO THE PREPARATION OF ROAD AND RAILWAY TUNNEL CONSTRUCTION IN THE AREA OF VÁCLAV HAVEL AIRPORT (RUZYNĚ).
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Jaroslav, Bárta, Tomáš, Belov, Josef, Buneš, Kateřina, Dvořáková, Peter, Hurbánek, Jaroslav, Jirků, Daniel, Reif, and Jaroslav, Reif
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TUNNELS ,RAILROAD design & construction ,TUNNEL design & construction ,RAILROAD tunnels ,HIGH speed trains ,GEOPHYSICS - Abstract
Copyright of EGRSE - Exploration Geophysics, Remote Sensing & Environment is the property of CAAG - Czech Association of Geophysicists and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2023
- Full Text
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7. Design and construction of Map Kabao Tunnel, longest rail tunnel in Thailand.
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Morya, Phichet, Chansutham, Tassawat, Phienwej, Noppadol, Chanrungautai, Sirisin, Inkoom, Pratuang, and Jongpradit, Pornkasem
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RAILROAD tunnels , *MAP design , *RAILROAD design & construction , *TUNNELS , *TUNNEL design & construction , *CLASTIC rocks , *RAILROAD safety measures - Abstract
Map Kabao Tunnel is a significant part of the track doubling project for the railway line connecting Bangkok to Northeast Thailand. The 5.2 km‐long twin‐tube tunnel makes is the longest railway tunnel in Thailand. The conventional tunnelling method was used to excavate the tunnel through complex geological conditions consisting of thrusted and folded carbonate and clastic sedimentary rocks. While encountering a few incidents of tunnelling difficulties caused by the poor quality of the rock mass attributed to weathering, sheared discontinuities, and karst features, the construction of the tunnel was ultimately successful and was completed in 2023. This article provides a comprehensive analysis of the lessons learned from the design and construction of this mountain rail tunnel project. [ABSTRACT FROM AUTHOR]
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- 2023
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8. Geotechnical challenges and innovations in urban underground construction – The Klang Valley Mass Rapid Transit project.
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Khoo, Chee‐Min and Ooi, Teik‐Aun
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UNDERGROUND construction , *PUBLIC transit , *TUNNELS , *RAILROAD tunnels , *TUNNEL design & construction , *ENGINEERING design , *DIRECTIONAL drilling - Abstract
The Klang Valley Mass Rapid Transit (KVMRT) project involves the construction of an urban passenger transport system, i.e., Mass Rapid Transit (MRT) system, together with the existing urban rail network, will form the backbone of the public transport system in the Greater Kuala Lumpur/Klang Valley region in Malaysia. The first MRT line implemented is the 47 km Kajang Line, of which 9.5 km is underground tunnels with seven underground stations. Construction of the line began on 8 July 2011 and achieved the full line opening on 17 July 2017. The second MRT line―Putrajaya Line―began fully operations on 16 March 2023, stretches from Sungai Buloh to Serdang and ends at Putrajaya for a length of 57.7 km, of which 13.5 km is underground tunnels with 10 new underground stations. Like all other metro underground stations/tunnels designed as part of the urban city, the KVMRT underground construction faces challenges from a technical (engineering design and construction) as well as social (environmental and land related) point of view. Needless to say, underground construction in Klang Valley is intensified with the inherent geotechnical challenges presented by complex ground conditions ranging from hard granite, heterogeneous Kenny Hill formation and extreme karstic limestone with fully developed weathered profiles to soft recent deposits including alluvium and mine tailing that is under‐consolidated in places due to past mining activities. The development of this large‐scale infrastructure project has not only opened up tremendous works and new frontier for tunnelling and geotechnical engineering in Malaysia, but it also provided a wealth of information of unique geotechnical challenges/accomplishments as well as technology breakthrough and design innovation in underground engineering. This article discusses some aspects of geotechnical challenges and interesting lessons learnt as well as numerous innovations embedded into this highly complex urban underground construction project. [ABSTRACT FROM AUTHOR]
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- 2023
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9. Las Leñas International Tunnel – Geomechanical challenges in large‐scale tunneling projects across The Andes.
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Orellana, Rodrigo, Höfer‐Öllinger, Giorgio, Ulloa, Juan Carlos, and Flores Bertoglio, Alejandro
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INFRASTRUCTURE (Economics) , *NUMERICAL analysis , *ROCK bursts , *ENGINEERING geology , *ROCKFALL - Abstract
Developing large‐scale tunnelling projects in orogenic regions implies enormous technical challenges. Las Leñas International Tunnel Project through the Andes Main Cordillera of Chile and Argentina has been a long‐awaited infrastructure project, whose geological and topographic settings suggest several complex singularities to be considered, analyzed, and assessed during its development. Throughout the course of this feasibility study, the complex geological subsurface interpretation offers a broad spectrum of technical demands to be fulfilled. The overburden conditions, the presence of certain lithologies such as expansive clays or soluble evaporitic sequences, along with regional stress assessment, are major technical challenges. Through extensive geological, geotechnical, and hydrogeological mapping, subsurface 3D modelling interpretation, along with numerical analysis and its relationship with similar projects in the region, brittle, and plastic behaviour are analyzed. A wide range of modern techniques are used to assess those mentioned tasks, which enable an extensive comprehension of the geological and geotechnical conditions of the area. The purpose of this contribution is to enrich the knowledge on geological and geomechanical challenges faced in large tunnelling infrastructure projects in high‐mountain environments and what specific lessons may arise from them for similar future projects. [ABSTRACT FROM AUTHOR]
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- 2023
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10. ASPECTE TEORETICO-CONCEPTUALE CU PRIVIRE LA INTITULAREA DOMENIULUI JURIDIC PREOCUPAT DE PROTECȚIA FACTORILOR DE MEDIU
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Andrian CREȚU
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mediu ,ecologie ,factori de mediu ,componente antropice ,geologie ,biologie. ,Law - Abstract
Cunoașterea cu precizie a sferei de cuprindere ce aparține unui domeniu sau ramuri de drept este o condiție indispensabilă evoluției oricărei ramuri din sistemul dreptului. Este și cazul dreptului mediului. În pofida diferitelor dezbateri asupra denumirii corecte a ramurii preocupate de protecția factorilor de mediu, lansate în spațiul doctrinar încă din momentul apariției sale, astăzi tot mai mulți specialiști dedicați domeniului utilizează sintagma „dreptul mediului” atunci când se referă la relațiile juridice constituite cu ocazia protecției juridice a mediului, dezvoltării, conservării și folosirii raționale a tuturor componentelor de mediu, inclusiv și cele antropice. Cu toate acestea, actualmente mai există unele controverse în privința certitudinii segmentului juridic de preocupare a ramurii de drept a mediului, fiind adesea confundat cu cel al științei ecologia, suprapus chiar la nivel de abordare științifică și didactică. Din respectivul considerent, am decis ca prin studiului de față să punem capăt discuțiilor ce complică și mai mult lucrurile, încercând a arăta că ecologia și mediul, respectiv, dreptul mediului sunt domenii distincte, deși foarte apropiate, corelate și coexistente în sistemul dreptului.
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- 2022
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11. Small‐diameter tunneling in difficult ground – Analysis of TBM performance in hard rock.
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Lehmann, Gabriel, Käsling, Heiko, Praetorius, Steffen, Seng, Frederic, and Thuro, Kurosch
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ROCK music , *TUNNEL design & construction , *TUNNELS , *PIPELINE transportation , *NATURAL gas pipelines - Abstract
Small‐diameter tunneling in hard rock is increasingly widespread due to the need for new and longer utility tunnels comprising sewer, stormwater, freshwater, or hydropower as well as cable tunnels and casings for pipelines transporting gas or hydrogen. Utility tunnels have to deal with a wide range of geological settings, like small overburden, weathered rock, rock–soil transitions, as well as fractured or intact hard rock with high strength and abrasivity. A database has been created including 35 hard rock projects with diameters between 1 and 5 m as well as more than 70,000 m of tunnel alignments, with a median drive length of less than 500 m. Challenges in creating it and some early interpretations based on the contents of the database are presented. Details about an exemplary pipe jacking project in basement rocks in Brittany, France, are given. The large variety in this small‐diameter range in hard rock includes different TBM types, cutterhead designs, cutter types, and geotechnical conditions. Potential pitfalls in small‐diameter TBM data analysis are shown and general drive parameter trends and penetration prediction approaches are presented and set in relation to the geotechnical conditions. Our analysis shows that difficult ground conditions do not only incorporate rocks with very high strength, but also generally weak rocks like schist or limestone could be responsible for low penetration rates and high thrust forces. [ABSTRACT FROM AUTHOR]
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- 2023
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12. Automated geological model updates during TBM operation – An approach based on probabilistic machine learning concepts.
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Wellmann, Florian, Amann, Florian, de la Varga, Miguel, and Chudalla, Nils
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GEOLOGICAL modeling , *CONCEPT learning , *BAYESIAN field theory , *MACHINE learning , *PREDICTION models , *ENGINEERING geology , *GROUND penetrating radar - Abstract
Geological models are commonly used to predict the position of relevant geological features, such as rock types or faults in the subsurface. These models can contain significant uncertainties, as the geological input parameters are often not perfectly known. Predictions of geological features, for example, on the level of a tunnel during an excavation process, are therefore uncertain. This work shows how these uncertainties can be estimated using probabilistic concepts. Furthermore, an approach is presented to automatically adjust the geological model predictions using measurements of the tunnel boring machine (TBM) operation. To this aim, the geological forward model is combined with a measurement model and both are integrated in a probabilistic machine learning framework. This integration enables a Bayesian inference process using computational methods, enabling an update of the parameters of the geological and measurement models. Based on the inferred parameter distributions, the model predictions on the tunnel level are subsequently updated. The application of the concept in a simple schematic application shows that such a combination can accurately and precisely predict features ahead of the operation within the limits of the model capabilities. In future work, the methods need to be tested with a real case study to evaluate the accuracy of predictions using real‐world TBM data and more complex geological models. The framework presented here could directly be extended to this purpose. [ABSTRACT FROM AUTHOR]
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- 2022
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13. Limberg III pumped storage power station project – special challenges posed by logistics and the tunnelling systems of a large‐scale construction site in a high mountain region.
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Schorn, Roland, Rieder, Christian, and Hager, Andreas
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BUILDING sites , *TUNNEL design & construction , *CONSTRUCTION projects , *TUNNELS , *STORAGE , *MOUNTAIN soils , *MOUNTAINS - Abstract
Construction of the Verbund project Limberg III pumped storage power station is currently underway in the area of the Kaprun/Salzach power station group. Preliminary work started on 6 April 2021, the main construction work started on 7 January 2022 and the overall facility is scheduled to be commissioned the end of 2025. Kaprun has a long history in the construction of power stations. The Kaprun storage power stations in the 1950s were an outstanding engineering feat and is symbolic of the reconstruction efforts that took place in Austria in the wake of World War II. The power station facilities at the main and upper stage have been in existence since the 1950s and have since been continuously expanded. From 2006 to 2011 the all‐year‐round reservoirs Mooserboden and Wasserfallboden were extended to include the Limberg II pumped storage station. The group is currently expanding the Kaprun/Salzach power station group by building the Limberg III pumped storage station, for which the same design as Limberg II has been adopted for implementation purposes. In addition to the significant logistical challenges posed by the high mountain location of the construction site, this report also covers the tunnelling systems. [ABSTRACT FROM AUTHOR]
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- 2022
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14. Scale formation processes – State of knowledge and current challenges.
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Dietzel, Martin and Eichinger, Stefanie
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DRAINAGE , *WATER tunnels , *CONSTRUCTION projects , *CONSTRUCTION materials , *TUNNELS , *CALCIUM carbonate - Abstract
Scale formation in water drainage systems occurs in diverse forms. In tunnel drainage systems in particular, calcium carbonate deposition can significantly impair water discharge, resulting in costly maintenance work and tunnel closures. This review paper presents and discusses the state of knowledge as well as the current challenges regarding scale formation in tunnel drainage systems in terms of typification, parameters controlling formation, such as hydrochemistry, interfacial phenomena, microbial activity, and countermeasures, such as appropriate adaptation of construction materials, drainage design, inhibitor use and cleaning. Detailed knowledge of the case‐specific scale formation environment and the scaling capacities of the waters provides the basis for the tailored development and evaluation of suitable strategies for successfully reducing maintenance efforts and tunnel closure. For this purpose, time‐ and site‐resolved monitoring of the composition of the solid phases, waters and the tunnel atmosphere during the implementation of the construction project and during the operation of the tunnel is paramount. [ABSTRACT FROM AUTHOR]
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- 2022
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15. Reduction of scale formation by optimized drainage conditions – Insights from field testing.
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Boch, Ronny, Pilgerstorfer, Thomas, and Moritz, Bernd
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DRAINAGE , *WATER hardness , *IRON ores , *MICROBIAL mats , *MINERAL waters - Abstract
A field test was carried out in Koralmtunnel in order to enhance process understanding and to optimize the drainage system in a tunnel section that is complex in terms of hydrochemistry, water inflow and mineral (calcareous scale, iron ochre) and biological (microbial mats) deposits. The field test comprised three test fields with different system components and flow characteristics. The development of critical waters and deposits was recorded by continuous measurements of relevant water and air parameters by means of autonomous sensors/data loggers. Furthermore, the components were "forensically" examined with respect to scale formation. The experiments show the crucial importance of gas exchange (CO2, oxygen ingress), filling level (flow geometry/regime), residence time of waters and water‐air interaction in the drainage system. The type, material consistency, and amount of scale and biofilms depend significantly on specific gradients. Floating scale crusts formed in stagnant sections, biofilms and iron ochre deposits of soft consistency formed at higher flow rates. Seepage packs and siphons turned out to be potential sediment traps with decreasing flow‐through with no access. Drainage hoses and dimpled membranes tend to be beneficial because they can prevent air exchange at relatively high flow rates. High CO2 partial pressure within these components (measured and modeled) inhibits carbonate precipitation. The drainage system is locally designed as a series of direct cross‐drains with simple flow paths, restricted air exchange, precautionary cleaning access, and optional water hardness stabilization (liquid conditioning). [ABSTRACT FROM AUTHOR]
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- 2022
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16. Current developments of digital ground modelling in tunnelling.
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Exenberger, Hans, Massimo‐Kaiser, Ines Maria, and Flora, Matthias
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COMPUTER software development , *COMPUTER art , *BUILDING information modeling - Abstract
This article analyses and discusses the current state of the art in the development of digital ground models in tunnelling. Following a review and discussion of the literature research combined with interview responses, a deficit analysis was performed. It shows why current projects mainly work with models and software that function as isolated solutions. A lack of software developments and limited collaborative work mean that the effects of current findings cannot immediately be implemented in models. Accordingly, the enormous potential of full coaction can only be imagined. A further problem is the lack of loss‐free data exchange across varying project phases and participants. Science is already moving in the right direction with the goal of harmonising the basic systematics. Finally, requirements for a digital ground model are formulated, and in combination with collaborative working and improved communication, these result in a large number of advanced possible applications. [ABSTRACT FROM AUTHOR]
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- 2022
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17. Automation and digitalisation of the geological documentation in tunnelling.
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Rabensteiner, Stefan, Weichenberger, Franz Peter, and Chmelina, Klaus
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GEOLOGICAL modeling , *TUNNEL design & construction , *BUILDING information modeling , *DOCUMENTATION , *AUTOMATION , *DIGITAL media , *INFORMATION storage & retrieval systems - Abstract
In tunnelling, the geological documentation comprises the daily recording and processing of various data for continuously assessing the geological–geotechnical conditions on‐site. One of the core tasks is the documentation of the tunnel face area. With Geodata's Tunnel Mapper, a new measuring system is presented enabling a highly automated data acquisition and the processing of a geo‐referenced three‐dimensional (3D) tunnel face model. Versions of the measuring system for both conventional and mechanised tunnelling have been developed. From the 3D model, high‐quality digital products as well as geometric and geological parameters can be derived, which serve as a basis for decisions on‐site. The data can then be integrated into the geological information system TUGIS.NET of Geoconsult, merged there with other data and further (geologically) evaluated, analysed and visualised. A spatial model that has been interpreted and quantified by the geologist can be established and used for target/actual comparisons and forecasts. The model can be transferred into building information modeling (BIM)‐compatible data structures for integration into an overall BIM model of the project. The further automation and digitalisation of the geological documentation and the full documentation (geometry and geology) of the face area are achieved in the interaction of the systems mentioned. [ABSTRACT FROM AUTHOR]
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- 2022
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18. Dr. Walter Biese (1895-1960) - Verspäteter Nachruf auf einen politisch verfolgten Geologen und Höhlenforscher.
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Knolle, Friedhart, Röhling, Heinz-Gerd, Brust, Michael K., and Danner, Peter
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KARST , *PALEONTOLOGY , *RESEARCH personnel , *CAVES , *MINING corporations , *ANHYDRITE , *POLITICAL persecution , *GEOLOGY - Abstract
The year 2022 marks the 100th anniversary of Dr Walter Biese's admission to the German Geological Society. Biese, whose life and work this paper is intended to commemorate, was a geologist, palaeontologist and speleologist from Berlin. He is considered a pioneer of research into the genesis of the gypsum and anhydrite caves in the southern Harz region and critically examined the formerly popular cave river theory. During the Nazi era, Walter Biese was banned from his profession due to social democratic activities. In 1934 he emigrated to Switzerland and from there to Chile in 1937. Walter Biese continued to be active in geology, palaeontology and speleology in these two countries. In Switzerland he compiled a cave register, while in Chile he first worked for a mining company and then as an independent geologist and on behalf of the government, mainly in the field of raw material exploration and regional mapping. In addition, he dedicated himself to palaeontology, botany and zoology, especially malacology. In 1959, he was awarded honorary membership of the Federation of German Cave and Karst Researchers. [ABSTRACT FROM AUTHOR]
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- 2022
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19. Geomechanical reservoir characterisation in Bavaria within the framework of the Geothermal‐Alliance Bavaria.
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Potten, Martin, Bohnsack, Daniel, Käsling, Heiko, and Thuro, Kurosch
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GEOTHERMAL resources , *DRILL cores , *CORE drilling , *CARBONATE rocks , *DRILL core analysis , *CARBONATES , *HYDROELECTRIC power plants , *COALBED methane - Abstract
To increase the use of geothermal energy in Bavaria, the subsurface, which serves as a reservoir, must be explored as precisely as possible. In the projects of the Geothermal‐Alliance Bavaria, the most promising areas for geothermal exploration in Bavaria were characterised based on an extensive geomechanical laboratory testing program which was carried out on both drill cores and analogue samples from quarries. In the North Alpine Foreland Basin (SE Germany), the geomechanical test results on Upper Jurassic carbonate rocks show a high heterogeneity. On the contrary, in the Franconian Basin (NE Bavaria) the geomechanical properties of granite analogues are rather homogenous. For the numerical simulation of the borehole stability, the determined parameters from ultrasonic‐ and compression tests serve as input parameters for different scenarios. For both locations, the determination of the failure depth around the borehole and the stress distribution in the near‐field of the borehole were accomplished. In the North Alpine Foreland Basin, the borehole stability decreases with increasing depth. For all scenarios in NE Bavaria, the borehole stability is very low. In the future, the determined parameter ranges will allow to validate already existing models and to develop new ones. This will enable a better knowledge of the sedimentary and crystalline reservoirs and a more effective use of geothermal energy in Bavaria. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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20. The rock mass as the governing factor for successfully developing deep geothermal systems in Southern Germany.
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Stockinger, Georg, Thuro, Kurosch, Moeck, Inga, and Straubinger, Robert
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GEOTHERMAL wells , *DRILL cores , *CORE drilling , *LIMESTONE , *DOLOMITE , *CARBONATES , *ROCK mechanics - Abstract
In Southern Germany, geothermal wells target Upper Jurassic carbonates, formerly referred to as Malm, below the Northern Alpine Foreland Basin (NAFB). In the northern, shallower carbonates (3000 m depth), e.g., in the Munich area, hydrothermal systems prevail, and wells yield proper flow rates. Deeper carbonates (< 4000 m) towards the south indicate a petrothermal system due to a decline in porosity and permeability. Inexplicably, fractures only contribute poorly to larger flow rates. This sets the goal for the project Dolomitkluft to analyse the rock mass for options countering low flow rates in two geothermal wells at Geretsried, Bavaria. Therefore, 20 m drill cores from 4600 to 4715 m total vertical depth (TVD) depict the initial structure of the rock mass: the rock parameters, the discontinuity network, and the in situ stresses. Alternating homogeneous, micritic, strong, to inhomogeneous, porous, weak limestones and massive, crystalline dolostones define the stratigraphy. Five joint sets from the cores can be distinguished into the bedding, two paleo anti‐ and synthetic normal faults and two recent strike‐slip faults. The latter, in combination with core disking, allows exclusively a strike‐slip (SS) stress regime and delimits the ratio to at least SH : Sv : Sh = 1.7 : 1.0 : 0.7. According to the results, including dilatation‐ and slip‐tendencies, drill trajectories of prosperous geothermal wells should head ESE/WNW, perpendicular to SS‐faults, and avoid the presence of normal faults. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
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21. Characterisation of the Upper Jurassic geothermal reservoir in the South German Molasse Basin as basis for a potential assessment to foster the geothermal installation development – Results from the joint research project Geothermal Alliance Bavaria
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Zosseder, Kai, Pfrang, Daniela, Schölderle, Felix, Bohnsack, Daniel, and Konrad, Florian
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MOLASSE , *GEOTHERMAL resources , *WATER temperature , *ROCK concerts , *TEST interpretation , *ROCK permeability , *DATA logging , *PROGNOSIS - Abstract
Geothermal energy applications are seen as one key element for a successful heat transition in Bavaria. But there are still some barriers for a further development. To minimize these barriers the joint research project Geothermal Alliance Bavaria (GAB) is established. One important issue to foster the implementations of geothermal projects is the assessment of geothermal load prediction in the South German Molasse Basin (SGMB). This includes, aside from a reservoir temperature prognosis, an accurate description of the hydraulic properties of the Upper Jurassic Malm reservoir. Hydraulic test analyses are conducted in the framework of the GAB to obtain specific information about the hydraulic productivity of the reservoir. Results from these analyses show a decrease of rock permeability in southern direction within the reservoir. Because the spatial distribution of hydraulic test data is limited, the porosity of the reservoir is assessed by borehole core tests and logs interpretation. A trend of matrix porosity decrease with depth is recognised and correlates with the hydraulic test results. Based on these findings and combined with further information the Upper Jurassic reservoir could be classified in separated zones of similar production rates, which can now be used for a thermal output prognosis for the Bavarian part of the SGMB. To spatially expand these prognoses more data must be investigated in the next research phase of the GAB. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
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22. Geomechanical effects of seasonal heat storage in abandoned mines.
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Bücken, Daniel, Meier, Tobias, and Backers, Tobias
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HEAT storage , *ABANDONED mines , *INDUCED seismicity , *SOLAR heating , *FAULT zones - Abstract
For the transition to sustainable heat sources, storage infrastructure is required to provide heat evenly throughout the year. Solar heat is typically produced in the summer and can be stored in underground heat reservoirs for the winter. Flooded coal mines, e.g., are potential heat reservoirs. To assess whether the geomechanical integrity of a colliery and the surrounding rock mass are affected by seasonally stored heat, a numerical case study was performed at "Zeche Dannenbaum" in the Ruhr valley, Germany. During summer, hot water was injected into level 8 of the colliery while cold water was produced from level 4. This process was reversed in winter. Detailed subsurface models of the colliery, rock mass and tectonic faults were used to numerically simulate the cyclical changes in pore pressure and temperature and the resulting stress changes. The displacement of the land surface, and geomechanically critical regions in the rock mass were derived. Moreover, the reactivation potential of the fault zones and the risk of induced seismicity were evaluated. The high injection temperatures induce strong thermoelastic effects, which could potentially lead to fault reactivation and induced seismicity. Surface displacements, however, are negligeable. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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23. Results of the EU H2020 project ThermoDrill – Contribution of rock mechanics to the utilization of geothermal energy.
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Stoxreiter, Thomas and Galler, Robert
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ROCK mechanics , *ENERGY consumption , *IMPACT (Mechanics) , *CARBON emissions , *DRILLING muds - Abstract
The urgent need to speed up the process of reducing CO2 emissions, as well as to stimulate the production and use of renewable energy demands sophisticated technologies to reach these goals. By developing an advanced drilling technology, the EU H2020 project ThermoDrill set itself the target to make the utilization of geothermal energy more economical. The new drilling technology is based on the combination of rotary drilling and high‐pressure fluid jetting. Rock mechanics largely contributes to the achievement of the common purpose of the project. Especially the investigation of the rock destruction process due to the combined hydraulic and mechanical impact plays a major role. The results are based on extensive experimental research concerning rock fracture under varying conditions. Additionally, various methods of crack detection are applied to identify the underlying mechanisms of the drilling technology. As a result, the specifications of the developed prototypes are to a considerable amount based on the rock mechanical findings. The huge potential of the advanced drilling technology is supported by the results of laboratory tests and field tests. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
24. 3D thermo‐hydro‐mechanical simulation of the behaviour of a naturally fractured petrothermal reservoir in deep Upper Jurassic carbonates of the Bavarian Molasse Basin – Case study Geretsried.
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Meneses Rioseco, Ernesto, Dussel, Michael, and Moeck, Inga S.
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MOLASSE , *FLUID injection , *FLUID flow , *INJECTION wells , *CARBONATES , *RESERVOIRS , *THERMAL stresses - Abstract
Based on multi‐scale and multi‐disciplinary measured data, gathered at the Geretsried geothermal site, a 3D reservoir model of the deep and fracture‐controlled Upper Jurassic carbonates in the North Alpine Foreland Basin is generated in this work. An efficient methodology is developed to numerically simulate the coupled reservoir processes of fluid flow, heat transport and thermoporoelastic stresses resulting from possible geothermal doublet operating schemes with cold fluid injection and production profiles in an enhanced naturally fractured reservoir. A variety of numerical experiments is conducted to study the reactivation potential and dilation tendency of the fracture and fault system. Simulation results show the spatiotemporal evolution of the thermoporoelastic stresses and the zone affected after 50 years of geothermal doublet operation. From these simulations, the thermoelastic response of a geothermal doublet operating with 60 °C fluid injection temperature and 20 l/s flow rate translates into a maximum induced thermal stress of around 49.4 MPa near the injection well. In terms of a long‐term reservoir performance and fault and fracture reactivation potential, the findings reveal a negligible risk to a sustainable geothermal doublet operation. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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25. Water jet drilling technology for application in geothermal environments.
- Author
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Hahn, Simon, Polat, Berker, Jamali, Shahin, Wittig, Volker, and Bracke, Rolf
- Subjects
- *
WATER well drilling , *RESERVOIR rocks , *HYDRAULICS , *ROCK music , *ROCK mechanics , *WATER jets - Abstract
High‐pressure water jet drilling technologies are widely used in the drilling industry. Especially in geothermal and hard rock applications, jet drilling is, however, confronted with several limitations like lateral length, hole size, steerability and jetability of the reservoir rock. The application of jet drilling technologies in the field can only be estimated based on the experience of the operator and surface experiments imitating downhole conditions. To predict a successful jetting operation in the field, a modelling framework has been developed, which considers operational and technical parameters as well as reservoir rock specifications. The framework consists of calibrated models describing downhole hydraulics and mechanics during the jetting operation and estimates the required technical equipment to successfully penetrate the reservoir rock and the maximum achievable lateral length for various hole configurations. The modelling framework is applied on a theoretical case study. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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- View/download PDF
26. Possible applications for a digital ground model in infrastructure construction.
- Author
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Gächter, Werner, Exenberger, Hans, Fasching, Alfred, Hillisch, Stefan, Mulitzer, Günther, Seywald, Martin, Rettenbacher, Martin, Fleischmann, Gregor, Fröch, Georg, and Flora, Matthias
- Subjects
- *
STRUCTURAL engineering , *INFORMATION superhighway , *INFORMATION modeling , *BUILDING information modeling , *KNOWLEDGE transfer - Abstract
The BIM pilot project "New Köstendorf‐Salzburg Line" for ÖBB‐Infrastruktur AG covers a new twin‐track section about 21 km long involving a wide variety of different engineering structures and a corresponding need for close interdisciplinary collaboration within a sensitive project space. The pilot project successfully achieved its objective of generating a largely software‐independent overall model and transferring the knowledge gained to the Employer's Information Requirements and subsequently to a BIM execution plan. In addition to internal coordination meetings, a preliminary external meeting took place to discuss the model elements required for a government agency as part of an approval process and the availability of such elements by means of direct access to the model. By adopting an integrated, collaborative approach to project management, it was possible to define extensive procedures and workflows adapted to the needs of the respective project partners for the single‐discipline models (specialist models) and to coordinate an overall federated model. The results of the co‐ordinated overall model show the ample opportunities afforded by a parameterised ground model for transparent risk and project assessment, paving the way for a holistic, phase‐based infrastructure information model. In this regard, the authors felt that it was important to adapt the project partners' established internal procedures only minimally and to translate them into BIM‐compatible, cooperative workflows. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
27. Towards the integration of smart techniques for tunnel seismic applications.
- Author
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Dickmann, Thomas, Hecht‐Méndez, Jozsef, Krüger, Dirk, Sapronova, Alla, Unterlaß, Paul Johannes, and Marcher, Thomas
- Subjects
- *
DATA transmission systems , *MACHINE learning , *DATA quality , *ARTIFICIAL intelligence , *ELECTRONIC data processing , *ROCK mechanics - Abstract
Applications of seismic measurements for the prediction of hazard zones are applied practice in many tunnel drives in rock mass today. Next to a large exploration range and accurate localisation of discontinuities, seismic data provide attributes for a comprehensive characterisation of the ground conditions. A good synchronisation of all technical components is required to obtain optimum data quality and quantity while the tunnel excavation is not obstructed thereby. Firstly, the signal source must feed as much energy as possible into the rock in a very short time. Secondly, continuity of the signal generation with constant quality and its precise timing by means of wireless data transmission also ensure a reliable measurement process. Artificial intelligence is used to determine the quality of the recorded data already in the tunnel and feedback is given to the user keeping the data quality high. From the tunnel site, recorded raw data can be transferred to a cloud, from where an authorised processor collects them, wherever in the world. An immediately started data processing delivers a result within an hour that includes a geological forecast of up to 150 m of heading, depending on the rock mass condition. In addition to data quality, the quality of the results is crucial. Therefore, techniques are currently under development using machine learning to correlate and analyse seismic attributes with geological properties. This should lead to a more objective evaluation of the geological forecast in the future. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
28. Innovative slurry solutions for demanding TBM drives through soil with high permeability in a dense urban area.
- Author
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Hochart, Arnaud and Vialle, Denis
- Subjects
- *
SOIL permeability , *CITIES & towns , *SLURRY , *TUNNEL design & construction , *HYDRAULIC circuits - Abstract
The extension of the Metro B line in Lyon represents a technical challenge combining difficulties with very few equivalents in pressurised TBM history. Alluviums with wide porosity and high permeability (up to 10–2 m/s) imply a risk of slurry loss leading to ground instabilities. To mitigate geological risks without using heavy ground treatment, two lines of research were followed: i) A slurry development program, aiming to define and validate technical mud formulae reducing the losses and ensuring the continuous confinement pressure. Two types of innovative slurries were to be defined, a "technical" one for horizons with high permeability, and an "emergency mud" to secure the tunnel and constructions in the event of a sudden slurry loss. ii) The use of a variably density TBM to use these technical slurries with a classic and an independent auxiliary hydraulic circuit. In addition, an embedded emergency mud supply was added to the TBM. The first phase implemented the slurry development lab, which consisted in the characterisation of a wide range of products entering in the slurry composition such as bentonite, mineral or organic clogging agents, polymers, gels, etc.. The slurry formulae were then tested under pressure in permeameters of two different sizes. Solutions clogging the porosity and sustaining mud and air pressure have been developed. The execution phase proved, that the developed solutions were giving the expected results regarding controlling slurry losses in the ground, maintaining front confinement pressure and reducing surface settlement below expected values in a dense urban area. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
29. S1 Tunnel Donau‐Lobau – The complex path to geological exploration in the Donau‐Auen National Park.
- Author
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Schröfelbauer, Thomas, Permanschlager, Katrin, Montag, Oliver, and Avender, Thomas
- Subjects
- *
NATIONAL parks & reserves , *CIVIL engineering , *TUNNELS , *CIVIL engineers , *TUNNEL design & construction , *SUBSOILS ,ENVIRONMENTAL compliance - Abstract
The S1 Donau‐Lobau tunnel closes the gap in the road network around Vienna. Its two tunnel tubes run under the Danube and the Donau‐Auen National Park, with the provision that no work is allowed to take place on the surface of the site. The (hydro‐)geological subsurface conditions in the project area can be described as "difficult". The tunnel project must also meet all safety‐related requirements that arise during construction and operation, while at the same time minimizing the environmental impact. This article describes the essential special civil engineering and tunnelling measures in connection with the local subsoil conditions. It outlines the geotechnical exploration goals required for the structural tendering and detailed planning as well as for limiting the subsoil risk. Just obtaining the necessary permits for the exploration work required extensive preparatory work. As a result, both the exploration programme and the tunnel itself have been further adapted. The approved explorations were completed in the shortest possible time in compliance with extensive environmental requirements during a single winter season. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
30. Highly specialized geophysical methods for undergroud construction works – Semmering Base Tunnel, a practice report.
- Author
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Radinger, Alexander, Hofmann, Thomas, Holzer, Robert, Fasching, Florian, and Kusnirak, David
- Subjects
- *
UNDERGROUND construction , *CONSTRUCTION projects , *GEOPHYSICAL prospecting , *TUNNEL design & construction , *GEOPHYSICAL surveys , *GEOLOGICAL modeling - Abstract
The use of geophysical methods for the planning of complex underground structures such as deep tunnels has made significant progress in the last two decades. The realization of large underground construction projects in complex geological environments has led to an increase of geophysical exploration during excavation activities, drilling, and geological documentation. The aim is to continuously update and improve the geological model in order to identify and mitigate potential risks. Flexible planning of geophysical measurements and their fast and efficient implementation are required to minimize the impact on ongoing construction works. During construction of the Semmering Base Tunnel geophysical measurements were and are used to supplement exploratory drillings and tunnel documentation. This paper presents results from the construction lots SBT1.1 (Gloggnitz) and SBT3.1 (Grautschenhof) with an emphasis on carbonate prediction, and from the Göstritz cavern where sudden water ingress required an update of the geologic model. For each assignment a tailored‐made geophysical methodology was designed and applied. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
31. Injection materials in tunnel excavation material – Waste or substitute construction material?
- Author
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Tintelnot, Götz and Koch, Michael
- Subjects
- *
CONSTRUCTION materials , *INJECTIONS , *SOIL protection , *TUNNEL design & construction , *EXCAVATION , *CEMENT , *BENTONITE , *CEMENT admixtures - Abstract
This paper examines the possibility of using excavated material with system‐related admixtures as a substitute construction material, considering the current rules and regulations in the field of landfilling or disposal. In addition to conventional injections with bentonite‐ and cement‐containing suspensions, which always require longer setting times and are relevant for classification during disposal with sulfate values in the eluate, fast‐setting multicomponent resins are suitable for filling or consolidation, e.g. fast‐reacting, high‐foaming silicate resins, polyurethane resins for stopping water ingress, or rubber‐elastic, versatile 3‐component acrylate gels. However, the discussion is currently focusing on tunnelling compounds to which foams or resins have been added and which, according to Systal's "system‐related admixtures", are to be remunerated as special services. This paper deals with the question how to deal with the excavated material contaminated with organic matter under soil protection law and waste law. On the basis of the results of laboratory tests, the question arises as to whether tunnel excavation with a few percent of organic, system‐related admixtures would not make an excellent substitute building material in the sense of the draft substitute building materials ordinance. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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- View/download PDF
32. Regard socio-anthropologique sur la géologie de terrain en sciences de la Terre
- Author
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Raineau Laurence
- Subjects
environnement ,ressources naturelles ,socio-anthropologie ,géologie ,interdisciplinarité ,Science ,Social Sciences - Abstract
Si dans le contexte environnemental actuel il devient difficile d’identifier une nature autonome et indépendante de l’Homme et de la société, quel est alors l’objet des sciences de la nature ? Nous proposons d’apporter ici une réponse à partir d’une enquête socio-anthropologique réalisée dans le cadre d’un projet interdisciplinaire à l’initiative des sciences de la Terre. Celle-ci nous a conduit à pointer l’importance du rapport au terrain dans la culture du géologue, même si ce terrain est souvent mis au second plan (ou disparaît même parfois) des publications en sciences de la Terre. Cette approche socio-anthropologique de la géologie, révélant la place du sujet dans la formation de la connaissance, permettra de conclure sur l’importance d’une réflexion pluridisciplinaire sur l’ethos du chercheur face aux enjeux environnementaux d’aujourd’hui.
- Published
- 2020
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33. Dynamic Mars : Recent and Current Landscape Evolution of the Red Planet
- Author
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Richard Soare, Susan Conway, Stephen M. Clifford, Richard Soare, Susan Conway, and Stephen M. Clifford
- Subjects
- SCIENCE / Astronomy, Planets--Geology, Geologie, Geomorphologie
- Abstract
Dynamic Mars: Recent and Current Landscape Evolution of the Red Planet presents the latest observations, interpretations, and explanations of geological change at the surface or near-surface of this terrestrial body. These changes raise questions about a decades-old paradigm, formed largely in the aftermath of very coarse Mariner-mission imagery in the 1960s, suggesting that much of the interesting geological activity on Mars occurred deep in its past, eons ago. The book includes discussions of (1) Mars'ever-changing atmosphere and the impact of this on the planet's surface and near-surface; (2) the possible involvement of water in relatively new, if not contemporary, gully-like flows and slope streaks (i.e. recurring slope lineae); and (3) the identification of a broad suite of agents and processes (i.e. glacial, periglacial, aeolian, meteorological, volcanic, and meteoric) that are actively revising surface and near-surface landscapes, landforms, and features on a local, regional, and hemispheric scale.Highly illustrated and punctuated by data from the most recent Mars missions, Dynamic Mars is a valuable resource for all levels of research in the geological history of Mars, as well as of the three other terrestrial planets. Utilizes observational and model-based data as well as geological context to frame the understanding of the dynamic surface and near-surface of Mars Presents a broad spectrum of highly regarded experts and themes to discuss and evaluate the geological history of late and current Mars Includes extensive and detailed imagery to clearly illustrate these themes, discussions, and evaluations
- Published
- 2018
34. Geologische und geophysikalische Untersuchungen
- Author
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Ernstson, Kord, Bauer, Mathias, editor, Freeden, Willi, editor, Jacobi, Hans, editor, and Neu, Thomas, editor
- Published
- 2018
- Full Text
- View/download PDF
35. Oberflächennahe Geothermie in der Schweiz
- Author
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Link, Katharina, Wyss, Roland, Bauer, Mathias, editor, Freeden, Willi, editor, Jacobi, Hans, editor, and Neu, Thomas, editor
- Published
- 2018
- Full Text
- View/download PDF
36. Use of artificial ground freezing in construction of cross passages under Suez Canal.
- Author
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Phillips, Mina, Fadhel, Haider, Raafat, Ibrahim, and El‐Kelesh, Adel
- Subjects
- *
TUNNELS , *WATERLOGGING (Soils) , *FREEZING , *GROUNDWATER , *SOIL freezing - Abstract
The Artificial Ground Freezing (AGF) has demonstrated its versatility as an effective approach for both temporary ground stabilization and ground water control in almost all types of saturated soils. This paper describes the use of a closed circuit freezing system in the construction of four cross passages. The passages connect 4.8 km long twin road tunnels that have recently been constructed at depths of up to 60 m under Suez Canal in Ismailia, Egypt. The paper starts by describing the ground conditions at the locations of the cross passages and by presenting the results of laboratory tests conducted on unfrozen, frozen and thawed soil specimens. The main design criteria considered in designing the freezing works are discussed and the freezing and cross passages construction works are described. The frozen body was carefully monitored during the freezing process and construction of passages. Records of the adopted monitoring program are presented and discussed. Significant observations that contribute to effective planning of future freezing works are also presented. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
37. Safety aspects of a water reservoir influenced by a creep like landslide.
- Author
-
Marte, Roman, Ausweger, Georg, Schweiger, Helmut F., Seiwald, Stephan, Kainz, Florian, and Breymann, Helfried
- Subjects
- *
LANDSLIDES , *AQUATIC sports safety measures , *HAZARD mitigation , *SOIL mechanics , *SAFETY factor in engineering - Abstract
On the basis of a case history of a pumping storage which is endangered by a slow moving landslide, the interaction of the reservoir operation and the deformation behaviour of the landslide will be discussed in this paper. Comprehensive measurements as well as theoretical investigations, which had been performed to understand the determining factors for the deformation behaviour of the landslide, will be discussed. Based on these investigation results a warn and alarm plan as part of the safety concept for the storage had been developed. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
38. Characterisation of rock as foundation for dams and hydropower plants – Experience from a field geologist's perspective.
- Author
-
Dietler, Thomas
- Subjects
- *
WATER power , *GEOLOGISTS , *GEOLOGICAL surveys , *GEOLOGY - Abstract
The characterisation of rock as a foundation for hydropower plants in general and dams in particular is highly complex and requires a great deal of experience on the part of the geologists involved. Geology cannot be studied remotely; it requires geological field surveys and investigations. This paper describes the aspects to be considered, the planning of the investigations and the degree of detail needed at the various planning phases from the field geologist's perspective. It also highlights the internationally recognised methods of investigation used for large‐scale projects and describes how the results are documented and recorded. It concludes by briefly outlining the soft factors which constitute an integral part of successful geological feasibility studies. Geology is an "inexact" science that requires extensive experience in order to generate the most realistic ground model possible. For this reason, a clear distinction must be made between facts (basic data) and their interpretation (experience). Furthermore, it is important to consider what other conclusions can be drawn from surveying the subsoil. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
39. Rodundwerk I, new headrace system – Concept and realization.
- Author
-
Innerhofer, Guntram and Bickel, Lukas
- Subjects
- *
BLASTING , *PLANT anatomy , *TUNNELS , *POWER plants , *CONCEPTS , *DECISION making - Abstract
As a result of several feasibility studies from which sound economic and technical arguments emerged, the decision was made to construct a new headrace system for the Rodundwerk I consisting of a low pressure tunnel, a shallow pressure shaft parallel to the surface slope and a subsequent high‐pressure penstock gallery. The new distribution pipeline was designed as a concrete‐encased gravity abutment. Construction started at the beginning of May 2020 and since then excavation work has progressed according to plan. Particular attention had to be addressed to the impact of construction operations on the existing power plant structures. Hence, a detailed monitoring concept was established concerning the vibration transmission in the rock mass. Excavation works are carried out partly by tunnel boring machine, partly by drilling and blasting and, once the critical threshold of vibration has been reached, by alternative methods. By continuously adjusting the blasting parameters (charge amount, ignition timing), it was possible to minimise the detonation‐related effects in the vicinity of the existing structures. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
40. De Zijpe en de Zuiderzee.
- Author
-
Borger, Guus J.
- Abstract
Dutch geologists and archaeologists disagree about the time the Flevo-lakes in the Wet Heart of the Netherlands were connected with the western part of the Waddenzee. Geologists hold the strong view that this connection originated in the centuries bc. Archaeological research revealed, however, that the pre-urban development of the city of Amsterdam did not start until the last quarter of the 12th century ad. This urban development has been considered as an indication that the shipping route between the mouth of the river Amstel and the Waddenzee had improved shortly before. Therefore, archaeologists are convinced that the improvement of this shipping route was forced by the All Saint's flood of 1170. To the west of Schagen, the sea is considered to have broken up the coastal barrier which led to the development of the Zuiderzee. Because of the etymological relation between the names Flevo and Vlie, the Flevo-lakes must have been already connected with the Waddenzee in the Roman period. Near Medemblik, however, the water did not become brackish before the 8th century ad and more to the south not earlier than the 9th century. Therefore, drainage must have been the main function of the connection between the Flevo-lakes and the Waddenzee for centuries. From historical documents it is known that somewhere around Stavoren a large amount of land was lost to the sea in 1170. Together with the swift development of Amsterdam it is likely that the Zuiderzee came into being after 1170. A breakthrough of the coastal barrier to the west of Schagen at that time, however, is unlikely. In 1170 there was some damage in the northern part of the province of Holland caused by a storm surge, but the loss of land was limited due to the building of several dikes. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
41. „IRIS-Baurohstoffe in Österreich" ist online!
- Author
-
Heinrich, Maria, Lipiarski, Piotr, Fritz, Ingomar, Heger, Horst, Knoll, Tanja, Lipiarska, Irena, Moshammer, Beatrix, Rabeder, Julia, Reischer, Johannes, Reitner, Heinz, Schedl, Albert, Schuberth-Hlavac, Gerald, Träxler, Barbara, and Untersweg, Thomas
- Abstract
Copyright of BHM Berg- und Hüttenmännische Monatshefte is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2021
- Full Text
- View/download PDF
42. Risk assessment of route options for the Hanau–Würzburg/Fulda railway project: Optimised exploratory concept and application of BIM in early project phases: Optimiertes Erkundungskonzept und Anwendung von BIM in frühen Projektphasen.
- Author
-
Wilfing, Lisa, Michael, Joachim, and Schütz, Dirk
- Subjects
- *
RAILROAD design & construction , *RISK assessment , *WATER table , *TUNNELS , *EMBANKMENTS - Abstract
In the course of the preliminary planning of the new Gelnhausen–Fulda railway line which is part of the railway project Hanau–Würzburg/Fulda, two route options with tunnels, bridges, cuts and embankments are to be investigated and assessed as efficiently as possible with regard to potential geotechnical risk areas. Due to the geological and hydrogeological conditions within the north‐eastern Hessian Buntsandsteingebirge, several groundwater levels, landslides in tunnel portal areas and karstification structures are to be expected on the two route options, each of which is approx. 45 km long. In order to obtain detailed and, above all, large‐scale knowledge of geotechnical hazards of each route = in the preliminary stage of the exploration programme, geophysical surface investigations are a cost‐ and time‐optimized exploration method in addition to standard drilling. These findings as well as existing subsurface information are combined by means of BIM, so that risk areas can be identified at an early stage of the project and taken into account when selecting the most affordable route. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
43. Besoins langagiers à l'oral chez les étudiants de 1ère année de géologie de l'Université d'Annaba.
- Author
-
Bouacha, Saida
- Subjects
FACE-to-face communication ,ORAL communication ,COMMUNICATIVE competence ,COLLEGE students ,FRENCH language ,CURRICULUM - Abstract
Copyright of Synergies Algérie is the property of GERFLINT (Groupe d'Etudes et de Recherches pour le Francais Langue Internationale) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2021
44. Using open-source software GRASS GIS for analysis of the environmental patterns in Lake Chad, Central Africa
- Abstract
Lake Chad, situated in the semi-arid region of African Sahel, plays a vital role in hydrogeological balance of regional ecosystems. It presents an essential water source and provides a habitat for rare wildlife species including migrating waterbirds. However, the lake has shrunk significantly since the 1960s and has continued to reduce in size and extent during recent decades. Trends in drying and shrinking of Lake Chad are caused by environmental factors and changed climate. The desiccation of the lake is threatening environmental sustainability. This study focused on identification of changes in the Chad Lake area, wetland extent, and associated land cover types. The methods include the Geographic Resources Analysis Support System (GRASS) Geographic Information System (GIS) for remote sensing data classification. The maximum likelihood discriminant analysis classifier was applied for analysis of multispectral Landsat 8–9 OLI/TIRS images in 2013, 2017, and 2022. Detected changes in land cover types reflect variations in water balance and wetland area and extent around Lake Chad over recent decades. Cartographic scripting tools of GRASS GIS provide an efficient method of digital image processing for monitoring endorheic lakes of Central Africa. GRASS GIS methods provide an opportunity to automatically classify Earth observation data with cartographic scripts for environmental monitoring., Der Tschadsee liegt in der halbtrockenen Region der afrikanischen Sahelzone und spielt eine entscheidende Rolle für das hydrogeolo- gische Gleichgewicht regionaler Ökosysteme. Es stellt eine wichtige Wasserquelle dar und bietet Lebensraum für seltene Wildtierarten, darunter auch wandernde Wasservögel. Allerdings ist der See seit den 1960er-Jahren erheblich geschrumpft und hat in den letzten Jahr- zehnten immer weiter an Größe und Ausdehnung abgenommen. Tendenzen zur Austrocknung und Schrumpfung des Tschadsees werden durch Umweltfaktoren und verändertes Klima verursacht. Die Austrocknung des Sees gefährdet die ökologische Nachhaltigkeit. Diese Studie konzentrierte sich auf die Identifizierung von Veränderungen im Gebiet des Tschadsees, der Feuchtgebietsausdehnung und den damit verbundenen Landbedeckungstypen. Zu den Methoden gehört das GRASS GIS zur Klassifizierung von Fernerkundungsdaten. Der Maximum-Likelihood-Diskriminanzanalyse-Klassifikator wurde für die Analyse multispektraler Landsat 8-9 OLI/TIRS-Bilder in den Jahren 2013, 2017 und 2022 angewendet. Die festgestellten Veränderungen in den Landbedeckungstypen spiegeln Schwankungen im Wasserhaushalt, in der Feuchtgebietsfläche und in der Ausdehnung rund um den Tschadsee in den letzten Jahrzehnten wider. Kartogra- fische Skriptwerkzeuge des GRASS GIS bieten eine effiziente Methode der digitalen Bildverarbeitung zur Überwachung endorheischer Seen in Zentralafrika. Die GRASS GIS-Methoden bieten die Möglichkeit, die Erdbeobachtungsdaten automatisch nutzend kartografi- schen Skripten für die Umweltüberwachung zu klassifizieren., SCOPUS: ar.j, info:eu-repo/semantics/published
- Published
- 2023
45. Structural controls on magma pathways in Bora-Baricha-Tullu Moye (BBTM) volcanic system, Main Ethiopian Rift
- Abstract
The Bora-Baricha-Tullu Moye (BBTM) volcanic complex is located at a transitional zone in the Main Ethiopian Rift where tectonic and volcanic features show complex interplays. We mapped and characterised volcanic and tectonic features using high-resolution digital elevation models and performed morphometric and vent spatial distribution analyses. Structural analysis reveals NNE–SSW, NE–SW, and NW–SE trending faults in the region. The dominant post-caldera volcanic landforms are lava domes, pumice cones, scoria cones, maars, obsidian coulees and lava flows, which have distinct morphological characteristics. Vent elongation and alignment highlight close association between these landforms and the caldera(s) as well as with tectonic structures, suggesting these structures acted as the main magma pathways during the BBTM recent eruptions. We estimate that during the entire BBTM post-caldera phase a total bulk volume of 10.9 km3 of material was erupted. This would represent a time-averaged magma flux of 0.05 km3 ky-1 in the BBTM., info:eu-repo/semantics/published
- Published
- 2023
46. Reconstructing the first moments after the Cretaceous-Paleogene boundary impact event: high-resolution petrography and geochemistry of proximal and distal Chicxulub impactites
- Abstract
The Chicxulub meteorite impact, ~66 million years ago, marks one of the most catastrophic events inEarth’s history. This event is linked to abrupt climate change and the Cretaceous-Paleogene (K-Pg)boundary mass extinction, responsible for the demise of 75% of life including the iconic non-aviandinosaurs. Fractured, molten, and vaporized rocks from the impact site were rapidly ejected into theatmosphere. This likely triggered the environmental stress at the K-Pg boundary, but the timing and exactmechanisms of these impact-induced processes are still poorly understood. The ~200-km-wide Chicxulubimpact structure, buried below the Yucatán Peninsula in México, forms a unique natural laboratory toinvestigate these processes. This crater is the only impact structure on Earth associated with ejectapreserved worldwide, which allows for a direct comparison between material from the source area and itsglobal deposits. In this PhD thesis, I present new high-resolution geochemical and petrographic analysis onrocks from the Chicxulub crater region and on globally distributed and well-preserved K-Pg boundaryejecta deposits. This work allows for a detailed reconstruction of the sequence of geological and biologicalevents that occurred in the moments prior, during and in the direct aftermath (minutes to years) of theChicxulub impact.The first part of this thesis is centered around crater suevites (impact-melt-bearing breccias)obtained from the Chicxulub northern peak ring by the recent IODP-ICDP Expedition 364 drilling campaign.The peak ring, consisting of granitoid basement, pre-impact dikes and impact melt bodies, was formed dueto the downward and outward collapse of the central uplift and this process took place within the first tenminutes after impact. The ~100 m thick suevite sequence on top is likely formed within 1 day after impactby the rapid arrival of ocean water in the crater that interacted with the underlying melt and subsequentlyflooded the crater basin. The overlying, Doctorat en Sciences, info:eu-repo/semantics/nonPublished
- Published
- 2023
47. Coherence of Bangui Magnetic Anomaly with Topographic and Gravity Contrasts across Central African Republic
- Abstract
The interactions between the geophysical processes and geodynamics of the lithosphere play a crucial role in the geologic structure of the Earth’s crust. The Bangui magnetic anomaly is a notable feature in the lithospheric structure of the Central African Republic (CAR) resulting from a complex tectonic evolution. This study reports on the coherence in the geophysical data and magnetic anomaly field analysed from a series of maps. The data used here include raster grids on free-air altimetric gravity, magnetic EMAG2 maps, geoid EGM2008 model and topographic SRTM/ETOPO1 relief. The data were processed to analyse the correspondence between the geophysical and geologic setting in the CAR region. Histogram equalization of the topographic grids was implemented by partition of the raster grids into equal-area patches of data ranged by the segments with relative highs and lows of the relief. The original data were compared with the equalized, normalized and quadratic models. The scripts used for cartographic data processing are presented and commented. The consistency and equalization of topography, gravity and geoid data were based using GMT modules ‘grdfft’ and ‘grdhisteq’ modules. Using GMT scripts for mapping the geophysical and gravity data over CAR shows an advanced approach to multi-source data visualization to reveal the relationships in the geophysical and topographic processes in central Africa. The results highlighted the correlation between the distribution of rocks with high magnetism in the central part of the Bangui anomaly, and distribution of granites, greenstone belts, and metamorphosed basalts as rock exposure. The correspondence between the negative Bouguer anomaly (<−80 mGal), low geoid values (<−12 m) and the extent of the magnetic anomaly with extreme negative values ranging from −1000 to −200 nT is identified. The integration of the multi-source data provides new insights into the analysis of crustal thicknesses and the average density of the Earth, SCOPUS: ar.j, info:eu-repo/semantics/published
- Published
- 2023
48. The 9th international conference on arctic margins (ICAM9) abstract volume
- Abstract
Ce rapport est une compilation des résumés présentés par les participants à la 9e Conférence internationale sur les marges arctiques (CIMA 9) qui s'est tenue à Ottawa, au Canada, du 13 au 15 juin 2022. La Conférence internationale sur les marges arctiques rassemble une communauté internationale de chercheurs en sciences de la Terre qui étudient l'océan Arctique et les masses continentales adjacentes. L'objectif de la CIMA 9 était de mettre en lumière l'état de la recherche géoscientifique de pointe sous-tendue par des collaborations nationales et internationales dans la région arctique. ICAM 9 a rassemblé plus de 80 participants provenant de huit nations. Le programme technique de l'ICAM 9 comprenait deux sessions spéciales et onze sessions techniques résultant d'un effort communautaire pour capturer un large éventail de résultats de recherche sous le thème "Par la lentille de l'Arctique.
- Published
- 2023
49. Passing a major fault zone three times: NATM helps TBM to succeed.
- Author
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Pilgerstorfer, Thomas, Hölzl, Harald, and Moritz, Bernd
- Subjects
- *
CONSTRUCTION delays , *SOLUTION strengthening , *UNITS of time , *RISK assessment - Abstract
This paper discusses the design and construction of a fault zone of the OeBB Koralmtunnel lot KAT3. Due to the experience gained during the advance of the parallel‐situated southbound tunnel and the aim to minimize the geotechnical hazard for the subsequent excavation of the northbound TBM bore, an extensive redesign regarding the excavation‐concept and ‐method was performed. Five different alternative solutions have been subject to a risk analysis to optimize the required measures and to minimize the cost‐effective risks and hazards to an acceptable level. The set of measures, which was evaluated and juxtaposed, contained solutions for strengthening the rock mass with grouting from the TBM and from aside the bore, conventional tunnelling and backfill with a top heading or full‐face excavation. Finally, the fault zone has been excavated with a conventional top heading drive from a nearby‐situated cross‐passage. Subsequently this tunnel stretch has been excavated by TBM without any construction delay. The paper focuses on highlighting the importance of a consequent application of the observational method and thereof derived measures in the context of a geotechnical safety management plan for controlling the residual risks. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
50. Semmering Base Tunnel – Tunnelling in challenging geotechnical and geological conditions in major fault zones.
- Author
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Holzer, Robert, Prall, Karoline, Wagner, Oliver Kai, and Gobiet, Gerhard
- Subjects
- *
FAULT zones , *TUNNELS , *TUNNEL design & construction , *HYDROGEOLOGY , *GROUNDWATER , *WATER hardness - Abstract
One of the major fault zones in the Semmering area runs along the Auebach Valley. In this fault zone a combination of soft fault rocks and water bearing hard rocks led to extremely challenging conditions in the design and execution of the tunnel. In difficult conditions, overlapping exploratory drillings in front of tunnel drive are essential to improve the geological‐hydrogeological model and to assess geotechnical risks. However, in the encountered geological‐hydrogeological conditions, the well‐established exploratory drilling methods reached their limits. Despite the ongoing risk analysis, a very large‐scale water and ground inflow with subsequent tunnel face collapse and development of a sinkhole on the surface occurred during the tunnelling. This paper describes the causes of the incident and the development of procedures to cope with the problem. In addition to the geological‐geotechnical analyses, the article also discusses the limitations of geotechnical surveillance in complex heterogeneous rock masses. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
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