503 Works

Recrystallization and deformation mechanisms in the NEEM deep ice core, Greenland

Ernst-Jan Kuiper, Martyn Drury, Gill Pennock, Hans de Bresser & Ilka Weikusat
Utrecht University, The Netherlands (1); Alfred Wegener Institute, Bremerhaven, Germany (2)

Understanding the evolution of lower latitude climate from the most recent glacial period of the latest Pleistocene to post glacial warmth in the continental tropical regions has been obstructed by a lack of continuous time series. Here we present results from a lacustrine record from tropical North America. Specifically, we examine sediments from Lake Chalco, located in the Valley of Mexico, central Mexico...

Milankovitch-scale paleoclimatic variability recorded in Permian loessite (south-central France)

Lily S.r Pfeifer, Linda Hinnov, Christian Zeeden, Christian Rolf & Christian) Laag
University of Oklahoma, USA (1); Department of Atmospheric, Oceanic, and Earth Sciences, George Mason University, Fairfax, VA, USA (2); Leibniz Institute for Applied Geophysics, Hanover, Germany (3); Institut de Physique du Globe de Paris (IPGP), CNRS, Université de Paris, Paris, France (4)

We present the findings from our recent paper wherein rock magnetic data record discernible Milankovitch-scale paleoclimatic variability through the Permian Salagou Formation loessite (south-central France). Analysis and modeling of this stratigraphic...

North Atlantic sea surface temperature evolution across the Eocene–Oligocene transition

Ilja Japhir Kocken, Kasper van der Veen, Inigo R. Müller, Anna Nele Meckler & Martin Ziegler
Utrecht University, The Netherlands (1); Unviersity of Bergen, Norway (2)

The Eocene–Oligocene Transition (EOT, ~34 Ma), is marked by the rapid development of semi-permanent Antarctic ice-sheet1. Foraminiferal stable oxygen isotopes (δ18O) as well as Mg/Ca and other indicators (e.g. ice-rafted debris) indicate the development of permanent glaciation that potentially coincides with ~2.5 °Cdeep-sea cooling2. However, due to the nature of the δ18O proxy, uncertainties in the Mg/Ca concentrations of the palaeo-seawater, and calibration...

An anatectic model for albite-spodumene pegmatites from the Austroalpine Unit (Eastern Alps)

Tanja Knoll, Benjamin Huet, Ralf Schuster & Heinrich Mali
Geological Survey of Austria, Austria (1); Department of Applied Geosciences and Geophysics, Montanuniversität Leoben (2)

Albite-spodumene pegmatite are considered to be the product of extreme fractionation of melts or fluids deriving from large alkaline granite intrusions. Anatectic melts deriving from partially molten metasediments are in contrast not believed to be a possible source for such pegmatite. In the Austroalpine Unit of the Eastern Alps, albite-spodumene pegmatite are associated with simple pegmatite and relatively...


Sarah Musalizi & Gertrud E. Rössner
Bayerische Staatssammlung für Paläontologie und Geologie, München Department für Geo- und Umweltwissenschaften, Ludwig- Maximilians-Universität München, Uganda

Chevrotains or mouse-deer (Tragulidae, Mammalia) are non-pecoran ruminant artiodactyls that are considered to have branched off the Ruminantia stem lineage during the late Eocene or Oligocene to Early Miocene. Extant tragulids live in central Africa (Hyemoschus) and South to Southeast Asia (Moschiola, Tragulus).The fossil record is reported to have been more diverse in phenotypes with a wider Afro-Eurasian...

Landslide susceptibility mapping on the country scale with data mining techniques in Armenia

Agnieszka Ledworowska, Anika Braun, Hans-Balder Havenith & Tomás Manuel Fernández-Steeger
Engineering Geology, Technische Universität Berlin, Germany (1); Department of Geology, University of Liège, Belgium (2)

Armenia is a country strongly affected by landslides, but still not enough research has been done on landslide susceptibility in this area. Therefore, the main goal of the study was to create one of the first landslide susceptibility zonation maps covering the entire territory of Armenia. Two different data mining techniques for landslide susceptibility analysis were applied: artificial...

Geoethics and the responsibility of Geoscientist in society: from research to teaching and outreach

Clara Vasconcelos (1) & Nir Orion (2)
Porto University, Portugal (1); Weizmann Institute of Science, Israel (2)

Geoethics emerged as the discipline that studies and reflects upon the values that underpin appropriate human behaviors and practices, whenever humans interact with the Earth. The foundations of geoethics are traced back to three main elements: the importance of geological culture as an essential part of the geoscientist’s background, the concept of responsibility (individual and social), and the definition of an ethical criterion...

Virtual Fieldtrips in Learning & Development: Geology 4 Non-Geologists - North Sea petroleum systems and reservoir geology, Dorset coast, UK

Jürgen Grötsch, Young Kon Yong & Maren Kleemeyer

Training courses in industry are being moved from face-to-face events to virtual equivalents for cost reasons but also for convenience, ie availability of online training where and when needed. This effort also comprises geological fieldtrips which in addition pose significant safety risks. On the other hand, acquiring 3D panoramic images, as well as drone footage in geological outcrops is nowadays inexpensive and easy to process due to hard- and software developments during the last...

Postnatal growth rates of the dwarf hippo Phanourios minor from the Pleistocene of Cyprus

Anneke H. van Heteren & P. Martin Sander
Cyprus, in the Pleistocene, was extremely isolated from a geological and biogeographical point of view. Only two macromammals successfully colonised the island before the Holocene: Elephas cypriotes, approximately 1.4 metres tall at the withers, and Phanourios minor. The latter is the smallest dwarfed hippo ever found; it stood 70 centimetres at the withers and weighed an estimated 200 kilograms, approximately 10% of its mainland ancestor’s weight. The main objective of this study was to determine...

Roots of the post-collisional Eocene magmatism in NE Turkey: Insights from ultramafic-mafic Yıldızdağ Gabbroic Intrusion

Gönenç Göçmengil (1), Zekiye Karacık (2) & Namık Aysal (3)
(1) Acıbadem, Kadıköy, İstanbul-Turkey; (2) İstanbul Teknik University, Geological Engineering Department, Turkey ; (3) Istanbul University- Cerrahpaşa, Geological Engineering Department, Turkey

Ultramafic-mafic cumulate rocks often situated at deep root zones of the magmatic systems when they intruded into continental crustal areas. In rare occurrences, they can also intrude at the middle to upper portion of the crust and record the MASH processes developed within the crust. Yıldızdağ Gabbroic Intrusion (YGI) represents one of the...

Critical Minerals in US Geothermal Brines: Opportunities and Challenges for their Extraction

Ghanashyam Neupane
Geothermal power plants produce a large volume of brine for power generation. Since these brines are the product of long-term water-rock interactions at elevated temperatures at depth, they contain dissolved chemical components including critical and strategic mineral commodities at various concentrations. Despite the low concentrations for many of these minerals, significant quantities of select minerals could be recovered due to the large volumes of brine utilized by geothermal power plants. Over the years, the U.S....

Wall rock contamination and mineralogical modifications in carbonatite dykes of the Palabora Complex, South Africa

R. Johannes Giebel , Benjamin F. Walter , Michael A.W. Marks & Gregor Markl
Contamination of carbonatite melts is often neglected due to a fast magma ascent and low liquidus temperatures. However, increased silicate mineral formation observed in numerous carbonatite occurrences world-wide requires an external Si introduction. Our study demonstrates that carbonatite dykes penetrating different lithologies of Palabora (South Africa) shows different modes of mineralogical modification. In particular Al and Si-rich lithologies show the most significant effects. Besides silicate mineral formation Si introduction may cause directly and indirectly variations...

Subduction initiation and arc evolution from a rear-arc perspective – A synthesis of results from IODP Exp. 351

Philipp A. Brandl
Subduction is a key process for the plate tectonic cycle and is responsible for the bimodal composition of the Earth’ crust. Whereas active subduction zones can be directly observed at many places, their initiation and the early evolution of the associated volcanic arc can only be studied from the geological record. One key location to study the geological processes related to subduction initiation and subsequent arc emergence and maturation is the Izu-Bonin-Mariana (IBM) subduction zone...

Thermo-compositional models of the West Gondwana cratons

Nils-Peter Finger , Mikhail K. Kaban , Magdala Tesauro , Walter D. Mooney & Maik Thomas
When Western Gondwana broke apart into the South American and African continents ca.120 Ma ago, some of its cratons were broken apart as well. Following the isopycnic hypothesis, their long-term stability and often neutral to positive buoyancy can be explained by the counteracting effects of cooling (density increase) and iron depletion (density decrease). To separate these effects, we created the presented models following an iterative integrated approach using mainly seismic and gravity data. In the...

Inverse modelling of transport distance to reduce ambiguities of microbial and chemical source tracking in karst catchments

Johannes Zirlewagen, Ferry Schiperski , Tobias Licha & Traugott Scheytt
The identification of contamination sources is vital for water protection, especially in highly vulnerable karst aquifers. Contamination sources might be distinguished by host-specific DNA markers of bacteria (Microbial Source Tracking, MST) or source-specific indicator compounds (Chemical Source Tracking, CST). These methods can help to identify a type of contamination source but fail to distinguish similar contaminant signals from different origins, e.g. multiple points of wastewater infiltration. Transport modelling can reduce these ambiguities by considering the...

µ-EDXRF based classification of chromites. A quick approach for testing hand specimen and drill cores.

Dieter Rammlmair & Wilhelm Nikonow
Chromites from ophiolites and layered intrusions show a wide variety in Cr#, Mg# and Cr/Fe ratios. These ratios provide information on the genesis of the chromite deposits e.g. the place of formation. By means of µ-EDXRF this information can be obtained in a very quick way from cut hand specimen. Unfortunately, chromites show a number of very intensive diffraction signals due to the polychromatic beam of the µ-EDXRF system, which even after calculating the minimum...

Experimental investigation of hydrogen storage and transport properties in reservoir rocks under the influence of abiotic chemical reactions, microbial metabolism, and \"in-situ\" pressures.

Nicolai Thüns, Garri Gaus , Ralf Littke & Helge Stanjek
RWTH Aachen, Clay and Interface Mineralogy(1);RWTH Aachen, Institute for Geology and Geochemistry of Petroleum and Coal(2);Temporary underground storage of molecular hydrogen (H2) in depleted oil and gas reservoirs has recently attracted increasing research interest as it can support chemical industry demands and peak-shaving in the energy supply grid. Experimental parameters related to abiotic chemical reactions, microbial metabolism, and transport mechanisms of molecular hydrogen under elevated pressure conditions in such reservoirs are of potential relevance to...

Mine water rebound in German hard coal mines – geochemical and petrophysical data support for an integrative monitoring plan

Henning Jasnowski-Peters, Barbara M.A. Teichert , Till Genth , Lisa Rose & Christian Melchers
Research Center of Post Mining, Technische Hochschule Georg Agricola University, Germany(1);Mine water rebound in German hard coal mine areas operated by RAG AG under the leadership of RAG Foundation is a showcase for post-mining associated research. It is a long-term, cost intensive and multidisciplinary project affecting highly populated urban areas like the Ruhr District. RAG is facing long-term liabilities as regulatory framework for the rebound process. Currently, mine water is pumped from levels down to...

Collecting, sharing, and visualising harmonised data on European raw materials occurrences and mines – success or failure?

Špela Kumelj , Lisbeth Flindt Jørgensen , Frands Schjøth , Andrej Vihtelič , Blaž Bahar & Katarina Hribernik
Geological Survey of Slovenia, Slovenia(1);Geological Survey of Denmark and Greenland, Denmark(2);Easy web access to useful and reliable mineral information for the whole of Europe is the main objective of the extension of the M4EU base in the GeoERA project Mineral Intelligence for Europe (MINTELL4EU). The foundation has been laid by previous projects such as Minerals4EU, ProSUM, SCRREEN, EuRare, ORAMA, and new ones have been added in collaboration with ongoing projects such as RESEERVE. Europe's geological...

Volcanites of MORB and WPB character in the evaporitic Permian Haselgebirge Formation (Eastern Alps, Austria) and possible tectonic implications

Christoph Leitner, Friedrich Finger & Albert Gilg
The evaporitic Haselgebirge Formation hosts in many places small occurrences of basaltic rocks. The geochemistry of these basalts can potentially provide information about the tectonic setting of the Haselgebirge Formation and the evolution of the Meliata ocean, respectively. XRD analysis and thin sections give hints to the original geochemistry, however the basalts altered significantly in contact with brines. Therefore, we present here 70 new XRF analyses of these basaltic rocks from various localities (Pfennigwiese, Annaberg,...

Reasons for extreme Th/U zoning of zircon in magmatic rocks: examples from the Bushveld Complex

Armin Zeh , Dominik Gudelius & Allan H Wilson
Zircons of magmatic rocks can show enormous variations in Th/U ratios (0.2 to 100) and extreme Th/U zoning. We present data from felsic and mafic rocks of the Bushveld Complex in South Africa. Zircon grains in mafic cumulate rocks reveal Th/U ratios up to 70, those in felsic rocks barely exceed 1.0. In mafic rocks zircon mostly occur together with Rt-Bt-Kfs-Qtz in intercumulus domains, and crystallized during final magma cooling between 900 and 700°C, after...

Time-dependent fracture permeability induced by fluid-rock interactions under intermittent and continuous flow

Chaojie Cheng & Harald Milsch
Fractures are the predominant flow pathways in low-permeability rocks. Understanding the fluid-rock interactions that occur in rock fractures and their effects on fracture aperture variations is important for assessing the sustainability of reservoir productivity. This study presents two long-term flow-through experiments with fractured pure quartz sandstones to investigate how fluid composition affects fracture changes over time. One sample was continuously flowed through with fluids (DI or Si-rich fluid), while the other sample was subjected to...

FloodRisk: Earthquakes, uplift, and long-term liabilities – risk minimisation during mine flooding

Dennis Quandt , Michael Alber , Felix Allgaier , Benjamin Busch , Even Markus , Kasper Fischer , Wolfgang Friederich , Jonas Greve , Mathias Knaak , Birgit Müller , Thomas Niederhuber , Detlev Rettenmaier , Martina Rische , Thomas Röckel , Frank Schilling , Daniel Schröder , Olaf Ukelis , Malte Westerhaus , Roman Zorn & Benjamin Busch
Due to the cessation of coal mining in Germany, mine water management in the former coal districts is subject to change and of environmental and economic significance. Since there is no technical need to drain the abandoned coal mines, mine water levels rise. As a result, subsurface rock pore pressures rise changing the subsurface effective stress regime. This may induce local ground movements and activate mining-related and natural fault zones. In order to develop a...

Recent case studies and advances of the magnetotelluric method in geothermal exploration

Friedemann Samrock
The magnetotelluric (MT) method is a well-established tool in geothermal exploration. Case studies from all over the world and from different geothermal settings have proven its effectiveness, when it comes to subsurface reservoir characterization and the successful siting of geothermal wells. A reason for MT being a popular tool in geothermal exploration is that the bulk electrical conductivity of the subsurface, as recovered by MT, can be used as a proxy for key geothermal parameters....

A Gaussian process regression model to determine solubility of calcium sulfate in aqueous fluids

Ali Sadighi , Reza Taherdangkooi & Christoph Butscher
The swelling of clay-sulfate rocks is a well-known phenomenon often causing threats to the success of different projects, for instance, geothermal drillings triggered swelling and ground heave with dramatic damages in Staufen, Germany. The origin of clay-sulfate swelling is usually explained by physical swelling due to clay expansion combined with chemical swelling associated with the transformation of anhydrite (CaSO4) into gypsum (CaSO4.2H2O). The swelling leads to about 60% of the volume increase of the rock...

Registration Year

  • 2022
  • 2021
  • 2020

Resource Types

  • Text
  • Other


  • Karlsruhe Institute of Technology
  • Helmholtz Centre Potsdam - GFZ German Research Centre for Geosciences
  • Federal Institute for Geosciences and Natural Resources
  • Technical University of Darmstadt
  • RWTH Aachen University
  • University of Bremen
  • University of Tübingen
  • Utrecht University
  • Kiel University
  • Ludwig-Maximilians-Universität München