9 Works

Subduction Dynamics and Rheology Control on Forearc and Backarc Subsidence: Numerical Models and Observations from the Mediterranean

Attila Balazs , Claudio Faccenna , Taras Gerya , Kosuke Ueda & Francesca Funiciello
The dynamics of subduction zones is linked to the rise and demise of forearc and backarc sedimentary basins in the overriding plate. Subsidence and uplift rates of these distinct basins are controlled by variations in plate convergence and subduction velocities and determined by the rheological and thermal structure of the lithosphere. In this study we conducted a series of high-resolution 2D numerical models of oceanic subduction and subsequent continental collision. The numerical code 2DELVIS involves...

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....

Cave monitoring of La Vallina Cave (NISA): Imprint of seasonality on δ13CDIC, δ18O and trace elements and the implications for speleothems

Oliver Kost , Saul Gonzalez Lemos , Laura Endres & Heather Stoll
A cave monitoring sets the basis of speleothem studies. It helps to understand changing cave conditions on seasonal scale and site-specific geochemical differences such as hydrological conditions and heterogeneities in bedrock respectively. Here we present a set of parameters measured in La Vallina Cave (NW Iberian Speleothem Archive, NISA). Over the course of 16 months cave air conditions (pCO2 and δ13C) were examined to understand calcite precipitation, ventilation processes and mixing of soil air and...

Decoupled dust deposition and ocean productivity in the Antarctic Zone of the Southern Ocean over the past 1.5 million years

Michael E. Weber , Ian Bailey , Sidney R. Hemming , Yasmina M. Martos , Brendan T. Reilly , Thomas A. Ronge , Stefanie Brachfeld , Trevor Williams , Maureen Raymo , Simon T. Belt , Hendrik Vogel , Victoria Peck , Linda Armbrecht , Alix Cage , Fabricio G. Cardillo , Zhiheng Du , Gerson Fauth , Christopher J. Fogwill , Marga Garcia , Marlo Garnsworthy , Anna Glüder , Michelle Guitard , Marcus Gutjahr , Iván Hernández-Almeida , Frida S. Hoem … & Xufeng Zheng
Southern Ocean paleoceanography provides key insights into how iron fertilization and oceanic productivity developed through Pleistocene ice-ages and their role in influencing the carbon cycle. We report the first high-resolution record of dust deposition and ocean productivity for the Antarctic Zone, close to the main dust source, Patagonia. Our deep-ocean records cover the last 1.5 Ma, thus doubling that from Antarctic ice-cores. We find a ≥10-fold increase in dust deposition during glacials and a ≤5-fold...

Geothermal Reservoir Characterisation and Probability Analysis of Fractured Media at Grimsel Test Site, Switzerland

Selvican Türkdogan & Peter Achtziger
Exploitation of deep geothermal energy is considered as one of the most efficient renewable energy applications. In this sense, reservoir stimulation is established to extract geothermal energy from EGS (Enhanced Geothermal System) which is highly dependent on its in-situ structural properties: damage/shear zones, faults, fractures, its statistics and characteristics. In more detail, damage zones may behave like a conduit providing preferential pathways for fluid flow in otherwise impermeable rock such as granite or gneiss. To...

Quantifying carbonate denudation from cosmogenic 36Cl and climatic and tectonic controls on carbonate landscape evolution

Richard F Ott , Sean F Gallen & David Helman
Department of Earth Sciences, ETH Zurich, Zurich, Switzerland(1);Earth Surface Geochemistry, German Centre for Geoscience Research, Potsdam, Germany(2);Department of Geosciences, Colorado State University, Fort Collins, US(3);Department of Soil and Water Sciences, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel(4);Advanced School for Environmental Studies, The Hebrew University of Jerusalem, Jerusalem, Israel(5);Quantifying carbonate denudation and the partitioning between chemical and mechanical surface lowering in karstic areas is challenging. Here...

Multi-proxy, localised reconstructions of climate and weathering from cave speleothem samples

Christopher Day , Philip Pogge von Strandmann , Franziska Lechleitner & Heather Stoll
Speleothems (secondary calcium carbonate formations) offer significant potential for recording environmental processes above caves, an area increasingly referred to as the Critical Zone. Speleothems grow for hundreds to millions of years, with absolute chronology from U-Th and U-Pb chronometers. The solution properties of rainwater infiltrating the soil and underlying caves respond to environmental controls. These environmental signals can be preserved within speleothem carbonates. Recent efforts to calibrate, model and interpret this complex geochemistry has progressed...

Numerical Modeling to Study the Impact of Pore Characteristics on the Electric Breakdown of Rock for Plasma Pulse Geo Drilling (PPGD)

Mohamed Ezzat , Daniel Vogler , Benjamin M. Adams & Martin O. Saar
Reducing the cost of drilling is crucial to economically extract deep geothermal energy as drilling costs can reach up to 70% of the total investment budget (Tester et al. 2006). Unfortunately, traditional mechanical rotary drilling is often far too expensive to enable economical geothermal energy extraction from many deep geologic settings due to the amount of energy rotary drilling requires and due to its significant drill bit wear, causing long, unproductive tripping times to exchange...

Combined Fluorescence Imaging and LA-ICP-MS Trace Element Mapping ofStalagmites: Microfabric identification and interpretation

Jakub Sliwinski & Heather Stoll
Here, we map a series of stalagmites from Asturias, Spain, by laser ablation inductively-coupled-plasma mass spectrometry and confocal laser scanning (fluorescence) microscopy and discuss the origins of trace element and fluorescence variations. Seasonal banding is evident with both methods and may be attributed to lignins/humic acids based on fluorescence absorption and emission characteristics. Some lateral variations in fluorescence present as saw-tooth “spires” and demonstrate disruptions of seasonal banding, corroborated by trace element variations (most prominently...

Registration Year

  • 2022

Resource Types

  • Text


  • ETH Zurich
  • University of Bern
  • Keele University
  • University of Adelaide
  • University of Plymouth
  • Spanish Institute of Oceanography
  • Columbia University
  • Andalusian Earth Sciences Institute
  • Oregon State University
  • University of California, San Diego