Articles | Volume 14, issue 3
https://doi.org/10.5194/se-14-237-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/se-14-237-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
06 Mar 2023
Research article |
| 06 Mar 2023
| 06 Mar 2023
Formation and geophysical character of transitional crust at the passive continental margin around Walvis Ridge, Namibia
Marine Geodynamics, Research Division 4: Dynamics of the Ocean Floor, GEOMAR
Helmholtz Centre for Ocean Research Kiel, Kiel, Germany
Marion Jegen
Marine Geodynamics, Research Division 4: Dynamics of the Ocean Floor, GEOMAR
Helmholtz Centre for Ocean Research Kiel, Kiel, Germany
Max Moorkamp
Geophysics, Department of Earth and Environmental Sciences, Ludwig Maximilian University of Munich, Munich, Germany
Christian Berndt
Marine Geodynamics, Research Division 4: Dynamics of the Ocean Floor, GEOMAR
Helmholtz Centre for Ocean Research Kiel, Kiel, Germany
Wolfgang Rabbel
Applied Geophysics, Institute of Geosciences, Christian-Albrechts University Kiel, Kiel, Germany
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Julie Christin Schindlbeck-Belo, Matthew Toohey, Marion Jegen, Steffen Kutterolf, and Kira Rehfeld
Earth Syst. Sci. Data, 16, 1063–1081, https://doi.org/10.5194/essd-16-1063-2024, https://doi.org/10.5194/essd-16-1063-2024, 2024
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Volcanic forcing of climate resulting from major explosive eruptions is a dominant natural driver of past climate variability. To support model studies of the potential impacts of explosive volcanism on climate variability across timescales, we present an ensemble reconstruction of volcanic stratospheric sulfur injection over the last 140 000 years that is based primarily on tephra records.
Damian L. Arévalo-Martínez, Amir Haroon, Hermann W. Bange, Ercan Erkul, Marion Jegen, Nils Moosdorf, Jens Schneider von Deimling, Christian Berndt, Michael Ernst Böttcher, Jasper Hoffmann, Volker Liebetrau, Ulf Mallast, Gudrun Massmann, Aaron Micallef, Holly A. Michael, Hendrik Paasche, Wolfgang Rabbel, Isaac Santos, Jan Scholten, Katrin Schwalenberg, Beata Szymczycha, Ariel T. Thomas, Joonas J. Virtasalo, Hannelore Waska, and Bradley A. Weymer
Biogeosciences, 20, 647–662, https://doi.org/10.5194/bg-20-647-2023, https://doi.org/10.5194/bg-20-647-2023, 2023
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Groundwater flows at the land–ocean transition and the extent of freshened groundwater below the seafloor are increasingly relevant in marine sciences, both because they are a highly uncertain term of biogeochemical budgets and due to the emerging interest in the latter as a resource. Here, we discuss our perspectives on future research directions to better understand land–ocean connectivity through groundwater and its potential responses to natural and human-induced environmental changes.
Felix Kästner, Simona Pierdominici, Judith Elger, Alba Zappone, Jochem Kück, and Christian Berndt
Solid Earth, 11, 607–626, https://doi.org/10.5194/se-11-607-2020, https://doi.org/10.5194/se-11-607-2020, 2020
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Knowledge about physical properties at depth is crucial to image and understand structures linked with orogenic processes. We examined seismic velocities from core and downhole data from the COSC-1 borehole, Sweden, and calibrated our results with laboratory measurements on core samples. Despite a strong mismatch between the core and downhole velocities due to microcracks, mafic units are resolved at all scales, while at sample scale, strong seismic anisotropy correlates with the rock foliation.
Christian Berndt, Sverre Planke, Damon Teagle, Ritske Huismans, Trond Torsvik, Joost Frieling, Morgan T. Jones, Dougal A. Jerram, Christian Tegner, Jan Inge Faleide, Helen Coxall, and Wei-Li Hong
Sci. Dril., 26, 69–85, https://doi.org/10.5194/sd-26-69-2019, https://doi.org/10.5194/sd-26-69-2019, 2019
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The northeast Atlantic encompasses archetypal examples of volcanic rifted margins. Twenty-five years after the last ODP leg on these volcanic margins, the reasons for excess melting are still disputed with at least three competing hypotheses being discussed. We are proposing a new drilling campaign that will constrain the timing, rates of volcanism, and vertical movements of rifted margins.
Ines Dumke and Christian Berndt
Solid Earth, 10, 1989–2000, https://doi.org/10.5194/se-10-1989-2019, https://doi.org/10.5194/se-10-1989-2019, 2019
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Knowing the velocity with which seismic waves travel through the top of the crust is important both for identifying anomalies, e.g. the presence of resources, and for geophysical data evaluation. Traditionally this has been done by using empirical functions. Here, we use machine learning to derive better seismic velocity estimates for the crust below the oceans. In most cases this methods performs better than empirical averages.
Sonja Geilert, Christian Hensen, Mark Schmidt, Volker Liebetrau, Florian Scholz, Mechthild Doll, Longhui Deng, Annika Fiskal, Mark A. Lever, Chih-Chieh Su, Stefan Schloemer, Sudipta Sarkar, Volker Thiel, and Christian Berndt
Biogeosciences, 15, 5715–5731, https://doi.org/10.5194/bg-15-5715-2018, https://doi.org/10.5194/bg-15-5715-2018, 2018
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Abrupt climate changes in Earth’s history might have been triggered by magmatic intrusions into organic-rich sediments, which can potentially release large amounts of greenhouse gases. In the Guaymas Basin, vigorous hydrothermal venting at the ridge axis and off-axis inactive vents show that magmatic intrusions are an effective way to release carbon but must be considered as very short-lived processes in a geological sense. These results need to be taken into account in future climate models.
Related subject area
Subject area: Crustal structure and composition | Editorial team: Seismics, seismology, paleoseismology, geoelectrics, and electromagnetics | Discipline: Geophysics
Post-Caledonian tectonic evolution of the Precambrian and Paleozoic platform boundary zone offshore Poland based on the new and vintage multi-channel reflection seismic data
Comparison of surface-wave techniques to estimate S- and P-wave velocity models from active seismic data
Complex fault system revealed by 3-D seismic reflection data with deep learning and fault network analysis
Advanced seismic characterization of a geothermal carbonate reservoir – insight into the structure and diagenesis of a reservoir in the German Molasse Basin
Electrical conductivity of anhydrous and hydrous gabbroic melt under high temperature and high pressure: implications for the high-conductivity anomalies in the mid-ocean ridge region
Utilisation of probabilistic magnetotelluric modelling to constrain magnetic data inversion: proof-of-concept and field application
Comparison of straight-ray and curved-ray surface wave tomography approaches in near-surface studies
3D deep geothermal reservoir imaging with wireline distributed acoustic sensing in two boreholes
3D high-resolution seismic imaging of the iron oxide deposits in Ludvika (Sweden) using full-waveform inversion and reverse time migration
Three-dimensional reflection seismic imaging of the iron oxide deposits in the Ludvika mining area, Sweden, using Fresnel volume migration
Drone-based magnetic and multispectral surveys to develop a 3D model for mineral exploration at Qullissat, Disko Island, Greenland
Ambient seismic noise analysis of LARGE-N data for mineral exploration in the Central Erzgebirge, Germany
Surface-wave tomography for mineral exploration: a successful combination of passive and active data (Siilinjärvi phosphorus mine, Finland)
Imaging crustal structures through a passive seismic imaging approach in a mining area in Saxony, Germany
Reverse time migration (RTM) imaging of iron oxide deposits in the Ludvika mining area, Sweden
Near-surface structure of the Sodankylä area in Finland, obtained by passive seismic interferometry
Evolution of the Iberian Massif as deduced from its crustal thickness and geometry of a mid-crustal (Conrad) discontinuity
Four-dimensional tracer flow reconstruction in fractured rock through borehole ground-penetrating radar (GPR) monitoring
Moho topography beneath the European Eastern Alps by global-phase seismic interferometry
Seismic imaging across fault systems in the Abitibi greenstone belt – an analysis of pre- and post-stack migration approaches in the Chibougamau area, Quebec, Canada
Wireline distributed acoustic sensing allows 4.2 km deep vertical seismic profiling of the Rotliegend 150 °C geothermal reservoir in the North German Basin
Sparse 3D reflection seismic survey for deep-targeting iron oxide deposits and their host rocks, Ludvika Mines, Sweden
Fault sealing and caprock integrity for CO2 storage: an in situ injection experiment
What can seismic noise tell us about the Alpine reactivation of the Iberian Massif? An example in the Iberian Central System
In situ hydromechanical responses during well drilling recorded by fiber-optic distributed strain sensing
Coherent diffraction imaging for enhanced fault and fracture network characterization
Seismic evidence for failed rifting in the Ligurian Basin, Western Alpine domain
Azimuth-, angle- and frequency-dependent seismic velocities of cracked rocks due to squirt flow
Characteristics of a fracture network surrounding a hydrothermally altered shear zone from geophysical borehole logs
Bayesian full-waveform inversion of tube waves to estimate fracture aperture and compliance
Correlation of core and downhole seismic velocities in high-pressure metamorphic rocks: a case study for the COSC-1 borehole, Sweden
Prediction of seismic P-wave velocity using machine learning
Large-scale electrical resistivity tomography in the Cheb Basin (Eger Rift) at an International Continental Drilling Program (ICDP) monitoring site to image fluid-related structures
Anisotropic P-wave travel-time tomography implementing Thomsen's weak approximation in TOMO3D
Full-waveform inversion of short-offset, band-limited seismic data in the Alboran Basin (SE Iberia)
Fault interpretation in seismic reflection data: an experiment analysing the impact of conceptual model anchoring and vertical exaggeration
Improving the quality of empirical Green's functions, obtained by cross-correlation of high-frequency ambient seismic noise
Quantifying the impact of the structural uncertainty on the gross rock volume in the Lubina and Montanazo oil fields (Western Mediterranean)
What happens to fracture energy in brittle fracture? Revisiting the Griffith assumption
Constraining the geotherm beneath the British Isles from Bayesian inversion of Curie depth: integrated modelling of magnetic, geothermal, and seismic data
Crustal-scale depth imaging via joint full-waveform inversion of ocean-bottom seismometer data and pre-stack depth migration of multichannel seismic data: a case study from the eastern Nankai Trough
Imaging the East European Craton margin in northern Poland using extended correlation processing of regional seismic reflection profiles
Ionian Abyssal Plain: a window into the Tethys oceanic lithosphere
Granite microporosity changes due to fracturing and alteration: secondary mineral phases as proxies for porosity and permeability estimation
3-D seismic travel-time tomography validation of a detailed subsurface model: a case study of the Záncara river basin (Cuenca, Spain)
The effect of rock composition on muon tomography measurements
Seismic imaging of dyke swarms within the Sorgenfrei–Tornquist Zone (Sweden) and implications for thermal energy storage
Quang Nguyen, Michal Malinowski, Stanisław Mazur, Sergiy Stovba, Małgorzata Ponikowska, and Christian Hübscher
Solid Earth, 15, 1029–1046, https://doi.org/10.5194/se-15-1029-2024, https://doi.org/10.5194/se-15-1029-2024, 2024
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Our work demonstrates the following: (1) an efficient seismic data-processing strategy focused on suppressing shallow-water multiple reflections. (2) An improvement in the quality of legacy marine seismic data. (3) A seismic interpretation of sedimentary successions overlying the basement in the transition zone from the Precambrian to Paleozoic platforms. (4) The tectonic evolution of the Koszalin Fault and its relation to the Caledonian Deformation Front offshore Poland.
Farbod Khosro Anjom, Frank Adler, and Laura Valentina Socco
Solid Earth, 15, 367–386, https://doi.org/10.5194/se-15-367-2024, https://doi.org/10.5194/se-15-367-2024, 2024
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Most surface-wave techniques focus on estimating the S-wave velocity (VS) model and consider the P-wave velocity (VP) model as prior information in the inversion step. Here, we show the application of three surface-wave methods to estimate both VS and VP models. We apply the methods to the data from a hard-rock site that were acquired through the irregular source–receiver recording technique. We compare the outcomes and performances of the methods in detail.
Thilo Wrona, Indranil Pan, Rebecca E. Bell, Christopher A.-L. Jackson, Robert L. Gawthorpe, Haakon Fossen, Edoseghe E. Osagiede, and Sascha Brune
Solid Earth, 14, 1181–1195, https://doi.org/10.5194/se-14-1181-2023, https://doi.org/10.5194/se-14-1181-2023, 2023
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We need to understand where faults are to do the following: (1) assess their seismic hazard, (2) explore for natural resources and (3) store CO2 safely in the subsurface. Currently, we still map subsurface faults primarily by hand using seismic reflection data, i.e. acoustic images of the Earth. Mapping faults this way is difficult and time-consuming. Here, we show how to use deep learning to accelerate fault mapping and how to use networks or graphs to simplify fault analyses.
Sonja H. Wadas, Johanna F. Krumbholz, Vladimir Shipilin, Michael Krumbholz, David C. Tanner, and Hermann Buness
Solid Earth, 14, 871–908, https://doi.org/10.5194/se-14-871-2023, https://doi.org/10.5194/se-14-871-2023, 2023
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The geothermal carbonate reservoir below Munich, Germany, is extremely heterogeneous because it is controlled by many factors like lithology, diagenesis, karstification, and tectonic deformation. We used a 3D seismic single- and multi-attribute analysis combined with well data and a neural-net-based lithology classification to obtain an improved reservoir concept outlining its structural and diagenetic evolution and to identify high-quality reservoir zones in the Munich area.
Mengqi Wang, Lidong Dai, Haiying Hu, Ziming Hu, Chenxin Jing, Chuanyu Yin, Song Luo, and Jinhua Lai
Solid Earth, 14, 847–858, https://doi.org/10.5194/se-14-847-2023, https://doi.org/10.5194/se-14-847-2023, 2023
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This is the first time that the electrical conductivity of gabbroic melt was assessed at high temperature and high pressure. The dependence of electrical conductivity on the degree of depolymerization was also explored. Electrical conductivity of gabbroic melts can be employed to interpret high-conductivity anomalies in the Mohns Ridge of the Arctic Ocean. This is of widespread interest to potential readers in high-pressure rock physics, solid geophysics, and deep Earth science.
Jérémie Giraud, Hoël Seillé, Mark D. Lindsay, Gerhard Visser, Vitaliy Ogarko, and Mark W. Jessell
Solid Earth, 14, 43–68, https://doi.org/10.5194/se-14-43-2023, https://doi.org/10.5194/se-14-43-2023, 2023
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We propose and apply a workflow to combine the modelling and interpretation of magnetic anomalies and resistivity anomalies to better image the basement. We test the method on a synthetic case study and apply it to real world data from the Cloncurry area (Queensland, Australia), which is prospective for economic minerals. Results suggest a new interpretation of the composition and structure towards to east of the profile that we modelled.
Mohammadkarim Karimpour, Evert Slob, and Laura Valentina Socco
Solid Earth, 13, 1569–1583, https://doi.org/10.5194/se-13-1569-2022, https://doi.org/10.5194/se-13-1569-2022, 2022
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Near-surface characterisation is of great importance. Surface wave tomography (SWT) is a powerful tool to model the subsurface. In this work we compare straight-ray and curved-ray SWT at near-surface scale. We apply both approaches to four datasets and compare the results in terms of the quality of the final model and the computational cost. We show that in the case of high data coverage, straight-ray SWT can produce similar results to curved-ray SWT but with less computational cost.
Evgeniia Martuganova, Manfred Stiller, Ben Norden, Jan Henninges, and Charlotte M. Krawczyk
Solid Earth, 13, 1291–1307, https://doi.org/10.5194/se-13-1291-2022, https://doi.org/10.5194/se-13-1291-2022, 2022
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We demonstrate the applicability of vertical seismic profiling (VSP) acquired using wireline distributed acoustic sensing (DAS) technology for deep geothermal reservoir imaging and characterization. Borehole DAS data provide critical input for seismic interpretation and help assess small-scale geological structures. This case study can be used as a basis for detailed structural exploration of geothermal reservoirs and provide insightful information for geothermal exploration projects.
Brij Singh, Michał Malinowski, Andrzej Górszczyk, Alireza Malehmir, Stefan Buske, Łukasz Sito, and Paul Marsden
Solid Earth, 13, 1065–1085, https://doi.org/10.5194/se-13-1065-2022, https://doi.org/10.5194/se-13-1065-2022, 2022
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Fast depletion of shallower deposits is pushing the mining industry to look for cutting-edge technologies for deep mineral targeting. We demonstrated a joint workflow including two state-of-the-art technologies: full-waveform inversion and reverse time migration. We produced Earth images with significant details which can help with better estimation of areas with high mineralisation, better mine planning and safety measures.
Felix Hloušek, Michal Malinowski, Lena Bräunig, Stefan Buske, Alireza Malehmir, Magdalena Markovic, Lukasz Sito, Paul Marsden, and Emma Bäckström
Solid Earth, 13, 917–934, https://doi.org/10.5194/se-13-917-2022, https://doi.org/10.5194/se-13-917-2022, 2022
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Methods for mineral exploration play an important role within the EU. Exploration must be environmentally friendly, cost effective, and feasible in populated areas. Seismic methods have the potential to deliver detailed images of mineral deposits but suffer from these demands. We show the results for a sparse 3D seismic dataset acquired in Sweden. The 3D depth image allows us to track the known mineralizations beyond the known extent and gives new insights into the geometry of the deposit.
Robert Jackisch, Björn H. Heincke, Robert Zimmermann, Erik V. Sørensen, Markku Pirttijärvi, Moritz Kirsch, Heikki Salmirinne, Stefanie Lode, Urpo Kuronen, and Richard Gloaguen
Solid Earth, 13, 793–825, https://doi.org/10.5194/se-13-793-2022, https://doi.org/10.5194/se-13-793-2022, 2022
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We integrate UAS-based magnetic and multispectral data with legacy exploration data of a Ni–Cu–PGE prospect on Disko Island, West Greenland. The basalt unit has a complex magnetization, and we use a constrained 3D magnetic vector inversion to estimate magnetic properties and spatial dimensions of the target unit. Our 3D modelling reveals a horizontal sheet and a strong remanent magnetization component. We highlight the advantage of UAS use in rugged and remote terrain.
Trond Ryberg, Moritz Kirsch, Christian Haberland, Raimon Tolosana-Delgado, Andrea Viezzoli, and Richard Gloaguen
Solid Earth, 13, 519–533, https://doi.org/10.5194/se-13-519-2022, https://doi.org/10.5194/se-13-519-2022, 2022
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Novel methods for mineral exploration play an important role in future resource exploration. The methods have to be environmentally friendly, socially accepted and cost effective by integrating multidisciplinary methodologies. We investigate the potential of passive, ambient noise tomography combined with 3D airborne electromagnetics for mineral exploration in Geyer, Germany. We show that the combination of the two geophysical data sets has promising potential for future mineral exploration.
Chiara Colombero, Myrto Papadopoulou, Tuomas Kauti, Pietari Skyttä, Emilia Koivisto, Mikko Savolainen, and Laura Valentina Socco
Solid Earth, 13, 417–429, https://doi.org/10.5194/se-13-417-2022, https://doi.org/10.5194/se-13-417-2022, 2022
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Passive-source surface waves may be exploited in mineral exploration for deeper investigations. We propose a semi-automatic workflow for their processing. The geological interpretation of the results obtained at a mineral site (Siilinjärvi phosphorus mine) shows large potentialities and effectiveness of the proposed workflow.
Hossein Hassani, Felix Hloušek, Stefan Buske, and Olaf Wallner
Solid Earth, 12, 2703–2715, https://doi.org/10.5194/se-12-2703-2021, https://doi.org/10.5194/se-12-2703-2021, 2021
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Passive seismic imaging methods use natural earthquakes as seismic sources, while in active seismic imaging methods, artificial sources (e.g. explosives) are used to generate seismic waves. We imaged some structures related to a major fault plane through a passive seismic imaging approach using microearthquakes with magnitudes smaller than 0.9 (Mw). These structures have not been illuminated by a previously conducted 3D active seismic survey due to their large dip angles.
Yinshuai Ding and Alireza Malehmir
Solid Earth, 12, 1707–1718, https://doi.org/10.5194/se-12-1707-2021, https://doi.org/10.5194/se-12-1707-2021, 2021
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In this article, we investigate the potential of reverse time migration (RTM) for deep targeting iron oxide deposits and the possible AVO effect that is potentially seen in the common image gathers from this migration algorithm. The results are promising and help to delineate the deposits and host rock structures using a 2D dataset from the Ludvika mines of central Sweden.
Nikita Afonin, Elena Kozlovskaya, Suvi Heinonen, and Stefan Buske
Solid Earth, 12, 1563–1579, https://doi.org/10.5194/se-12-1563-2021, https://doi.org/10.5194/se-12-1563-2021, 2021
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In our study, we show the results of a passive seismic interferometry application for mapping the uppermost crust in the area of active mineral exploration in northern Finland. The obtained velocity models agree well with geological data and complement the results of reflection seismic data interpretation.
Puy Ayarza, José Ramón Martínez Catalán, Ana Martínez García, Juan Alcalde, Juvenal Andrés, José Fernando Simancas, Immaculada Palomeras, David Martí, Irene DeFelipe, Chris Juhlin, and Ramón Carbonell
Solid Earth, 12, 1515–1547, https://doi.org/10.5194/se-12-1515-2021, https://doi.org/10.5194/se-12-1515-2021, 2021
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Vertical incidence seismic profiling on the Iberian Massif images a mid-crustal-scale discontinuity at the top of the reflective lower crust. This feature shows that upper- and lower-crustal reflections merge into it, suggesting that it has often behaved as a detachment. The orogen-scale extension of this discontinuity, present in Gondwanan and Avalonian affinity terranes into the Iberian Massif, demonstrates its relevance, leading us to interpret it as the Conrad discontinuity.
Peter-Lasse Giertzuch, Joseph Doetsch, Alexis Shakas, Mohammadreza Jalali, Bernard Brixel, and Hansruedi Maurer
Solid Earth, 12, 1497–1513, https://doi.org/10.5194/se-12-1497-2021, https://doi.org/10.5194/se-12-1497-2021, 2021
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Two time-lapse borehole ground penetrating radar (GPR) surveys were conducted during saline tracer experiments in weakly fractured crystalline rock with sub-millimeter fractures apertures, targeting electrical conductivity changes. The combination of time-lapse reflection and transmission GPR surveys from different boreholes allowed monitoring the tracer flow and reconstructing the flow path and its temporal evolution in 3D and provided a realistic visualization of the hydrological processes.
Irene Bianchi, Elmer Ruigrok, Anne Obermann, and Edi Kissling
Solid Earth, 12, 1185–1196, https://doi.org/10.5194/se-12-1185-2021, https://doi.org/10.5194/se-12-1185-2021, 2021
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The European Alps formed during collision between the European and Adriatic plates and are one of the most studied orogens for understanding the dynamics of mountain building. In the Eastern Alps, the contact between the colliding plates is still a matter of debate. We have used the records from distant earthquakes to highlight the geometries of the crust–mantle boundary in the Eastern Alpine area; our results suggest a complex and faulted internal crustal structure beneath the higher crests.
Saeid Cheraghi, Alireza Malehmir, Mostafa Naghizadeh, David Snyder, Lucie Mathieu, and Pierre Bedeaux
Solid Earth, 12, 1143–1164, https://doi.org/10.5194/se-12-1143-2021, https://doi.org/10.5194/se-12-1143-2021, 2021
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High-resolution seismic profiles in 2D are acquired in the north and south of the Chibougamau area, Quebec, Canada located in the northeast of the Abitibi Greenstone belt. The area mostly includes volcanic rocks, and both profiles cross over several fault zones. The seismic method is acquired to image the subsurface down to depth of 12 km. The main aim of this study is to image major fault zones and the geological formations connected to those faults to investigate metal endowment in the area.
Jan Henninges, Evgeniia Martuganova, Manfred Stiller, Ben Norden, and Charlotte M. Krawczyk
Solid Earth, 12, 521–537, https://doi.org/10.5194/se-12-521-2021, https://doi.org/10.5194/se-12-521-2021, 2021
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We performed a seismic survey in two 4.3 km deep geothermal research wells using the novel method of distributed acoustic sensing and wireline cables. The characteristics of the acquired data, methods for data processing and quality improvement, and interpretations on the geometry and structure of the sedimentary and volcanic reservoir rocks are presented. The method enables measurements at high temperatures and reduced cost compared to conventional sensors.
Alireza Malehmir, Magdalena Markovic, Paul Marsden, Alba Gil, Stefan Buske, Lukasz Sito, Emma Bäckström, Martiya Sadeghi, and Stefan Luth
Solid Earth, 12, 483–502, https://doi.org/10.5194/se-12-483-2021, https://doi.org/10.5194/se-12-483-2021, 2021
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A smooth transition toward decarbonization demands access to more minerals of critical importance. Europe has a good geology for many of these mineral deposits, but at a depth requiring sensitive, environmentally friendly, and cost-effective methods for their exploration. In this context, we present a sparse 3D seismic dataset that allowed identification of potential iron oxide resources at depth and helped to characterise key geological structures and a historical tailing in central Sweden.
Alba Zappone, Antonio Pio Rinaldi, Melchior Grab, Quinn C. Wenning, Clément Roques, Claudio Madonna, Anne C. Obermann, Stefano M. Bernasconi, Matthias S. Brennwald, Rolf Kipfer, Florian Soom, Paul Cook, Yves Guglielmi, Christophe Nussbaum, Domenico Giardini, Marco Mazzotti, and Stefan Wiemer
Solid Earth, 12, 319–343, https://doi.org/10.5194/se-12-319-2021, https://doi.org/10.5194/se-12-319-2021, 2021
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The success of the geological storage of carbon dioxide is linked to the availability at depth of a capable reservoir and an impermeable caprock. The sealing capacity of the caprock is a key parameter for long-term CO2 containment. Faults crosscutting the caprock might represent preferential pathways for CO2 to escape. A decameter-scale experiment on injection in a fault, monitored by an integrated network of multiparamerter sensors, sheds light on the mobility of fluids within the fault.
Juvenal Andrés, Puy Ayarza, Martin Schimmel, Imma Palomeras, Mario Ruiz, and Ramon Carbonell
Solid Earth, 11, 2499–2513, https://doi.org/10.5194/se-11-2499-2020, https://doi.org/10.5194/se-11-2499-2020, 2020
Yi Zhang, Xinglin Lei, Tsutomu Hashimoto, and Ziqiu Xue
Solid Earth, 11, 2487–2497, https://doi.org/10.5194/se-11-2487-2020, https://doi.org/10.5194/se-11-2487-2020, 2020
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Spatially continuous strain responses in two monitoring wells induced by a well-drilling process were monitored using high-resolution fiber-optic distributed strain sensing (DSS). The modeling results suggest that the strain polarities and magnitudes along the wellbores may be indicative of the layered-permeability structure or heterogeneous formation damage. The performance and value of DSS as a novel hydrogeophysical tool for in situ subsurface monitoring are emphasized.
Benjamin Schwarz and Charlotte M. Krawczyk
Solid Earth, 11, 1891–1907, https://doi.org/10.5194/se-11-1891-2020, https://doi.org/10.5194/se-11-1891-2020, 2020
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Intricate fault and fracture networks cut through the upper crust, and their detailed delineation and characterization play an important role in the Earth sciences. While conventional geophysical sounding techniques only provide indirect means of detection, we present scale-spanning field data examples, in which coherent diffraction imaging – a framework inspired by optics and visual perception – enables the direct imaging of these crustal features at an unprecedented spatial resolution.
Anke Dannowski, Heidrun Kopp, Ingo Grevemeyer, Dietrich Lange, Martin Thorwart, Jörg Bialas, and Martin Wollatz-Vogt
Solid Earth, 11, 873–887, https://doi.org/10.5194/se-11-873-2020, https://doi.org/10.5194/se-11-873-2020, 2020
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The Ligurian Sea opened ~30–15 Ma during the SE migration of the Calabrian subduction zone. Seismic travel time tomography reveals the absence of oceanic crust, documenting that the extension of continental lithosphere stopped before seafloor spreading initiated. The extension led to extreme crustal thinning and possibly exhumed mantle accompanied by syn-rift sedimentation. Our new interpretation of the crust's nature is important for plate reconstruction modelling related to the Alpine orogen.
Yury Alkhimenkov, Eva Caspari, Simon Lissa, and Beatriz Quintal
Solid Earth, 11, 855–871, https://doi.org/10.5194/se-11-855-2020, https://doi.org/10.5194/se-11-855-2020, 2020
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We perform a three-dimensional numerical study of the fluid–solid deformation at the pore scale. We show that seismic wave velocities exhibit strong azimuth-, angle- and frequency-dependent behavior due to squirt flow between interconnected cracks. We conclude that the overall anisotropy mainly increases due to squirt flow, but in some specific planes it can locally decrease as well as increase, depending on the material properties.
Eva Caspari, Andrew Greenwood, Ludovic Baron, Daniel Egli, Enea Toschini, Kaiyan Hu, and Klaus Holliger
Solid Earth, 11, 829–854, https://doi.org/10.5194/se-11-829-2020, https://doi.org/10.5194/se-11-829-2020, 2020
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A shallow borehole was drilled to explore the petrophysical and hydraulic characteristics of a hydrothermally active fault in the crystalline Aar massif of the Alps. A key objective of studying surficial features of this kind is to establish analogies with natural and deep-seated engineered hydrothermal systems. A wide range of geophysical borehole logs was acquired, which revealed a complex fracture network in the damage zone of the fault and a related compartmentalized hydraulic behavior.
Jürg Hunziker, Andrew Greenwood, Shohei Minato, Nicolás Daniel Barbosa, Eva Caspari, and Klaus Holliger
Solid Earth, 11, 657–668, https://doi.org/10.5194/se-11-657-2020, https://doi.org/10.5194/se-11-657-2020, 2020
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The characterization of fractures is crucial for a wide range of pertinent applications, such as geothermal energy production, hydrocarbon exploration, CO2 sequestration, and nuclear waste disposal. We estimate fracture parameters based on waves that travel along boreholes (tube waves) using a stochastic optimization approach.
Felix Kästner, Simona Pierdominici, Judith Elger, Alba Zappone, Jochem Kück, and Christian Berndt
Solid Earth, 11, 607–626, https://doi.org/10.5194/se-11-607-2020, https://doi.org/10.5194/se-11-607-2020, 2020
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Knowledge about physical properties at depth is crucial to image and understand structures linked with orogenic processes. We examined seismic velocities from core and downhole data from the COSC-1 borehole, Sweden, and calibrated our results with laboratory measurements on core samples. Despite a strong mismatch between the core and downhole velocities due to microcracks, mafic units are resolved at all scales, while at sample scale, strong seismic anisotropy correlates with the rock foliation.
Ines Dumke and Christian Berndt
Solid Earth, 10, 1989–2000, https://doi.org/10.5194/se-10-1989-2019, https://doi.org/10.5194/se-10-1989-2019, 2019
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Knowing the velocity with which seismic waves travel through the top of the crust is important both for identifying anomalies, e.g. the presence of resources, and for geophysical data evaluation. Traditionally this has been done by using empirical functions. Here, we use machine learning to derive better seismic velocity estimates for the crust below the oceans. In most cases this methods performs better than empirical averages.
Tobias Nickschick, Christina Flechsig, Jan Mrlina, Frank Oppermann, Felix Löbig, and Thomas Günther
Solid Earth, 10, 1951–1969, https://doi.org/10.5194/se-10-1951-2019, https://doi.org/10.5194/se-10-1951-2019, 2019
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An active CO2 degassing site in the western Eger Rift, Czech Republic, was investigated with a 6.5 km long geophysical survey using a specific large-scale geoelectrical setup, supported by shallow geoelectrical surveys and gravity measurements. The experiment reveals unusually low resistivities in the sediments and basement below the degassing area of less than 10 Ω and provides a base for a custom geological model of the area for a future 400 m deep research drilling in this area.
Adrià Meléndez, Clara Estela Jiménez, Valentí Sallarès, and César R. Ranero
Solid Earth, 10, 1857–1876, https://doi.org/10.5194/se-10-1857-2019, https://doi.org/10.5194/se-10-1857-2019, 2019
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A new code for anisotropic travel-time tomography is presented. We describe the equations governing the anisotropic ray propagation algorithm and the modified inversion solver. We study the sensitivity of two medium parameterizations and compare four inversion strategies on a canonical model. This code can provide better understanding of the Earth's subsurface in the rather common geological contexts in which seismic velocity displays a weak dependency on the polar angle of ray propagation.
Clàudia Gras, Daniel Dagnino, Clara Estela Jiménez-Tejero, Adrià Meléndez, Valentí Sallarès, and César R. Ranero
Solid Earth, 10, 1833–1855, https://doi.org/10.5194/se-10-1833-2019, https://doi.org/10.5194/se-10-1833-2019, 2019
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We present a workflow that combines different geophysical techniques, showing that a detailed seismic velocity model can be obtained even for non-optimal data sets, i.e. relatively short-offset, band-limited streamer data recorded in deep water. This fact has an important implication for the Marine seismic community, suggesting that many of the existing data sets should be revisited and analysed with new techniques to enhance our understanding of the subsurface, as in the Alboran Basin case.
Juan Alcalde, Clare E. Bond, Gareth Johnson, Armelle Kloppenburg, Oriol Ferrer, Rebecca Bell, and Puy Ayarza
Solid Earth, 10, 1651–1662, https://doi.org/10.5194/se-10-1651-2019, https://doi.org/10.5194/se-10-1651-2019, 2019
Nikita Afonin, Elena Kozlovskaya, Jouni Nevalainen, and Janne Narkilahti
Solid Earth, 10, 1621–1634, https://doi.org/10.5194/se-10-1621-2019, https://doi.org/10.5194/se-10-1621-2019, 2019
Carla Patricia Bárbara, Patricia Cabello, Alexandre Bouche, Ingrid Aarnes, Carlos Gordillo, Oriol Ferrer, Maria Roma, and Pau Arbués
Solid Earth, 10, 1597–1619, https://doi.org/10.5194/se-10-1597-2019, https://doi.org/10.5194/se-10-1597-2019, 2019
Timothy R. H. Davies, Maurice J. McSaveney, and Natalya V. Reznichenko
Solid Earth, 10, 1385–1395, https://doi.org/10.5194/se-10-1385-2019, https://doi.org/10.5194/se-10-1385-2019, 2019
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Griffith (1921) assumed that energy used to create new surface area by breaking intact rock immediately becomes surface energy which is not available for further breakage. Our lab data disprove this assumption; we created much more new surface area, 90 % on submicron fragments, than the energy involved should allow. As technology allows ever smaller fragments to be measured, continued use of the Griffith assumption will lead to incorrect energy budgets for earthquakes and rock avalanches.
Ben Mather and Javier Fullea
Solid Earth, 10, 839–850, https://doi.org/10.5194/se-10-839-2019, https://doi.org/10.5194/se-10-839-2019, 2019
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The temperature in the crust can be constrained by the Curie depth, which is often interpreted as the 580 °C isotherm. We cast the estimation of Curie depth, from maps of the magnetic anomaly, within a Bayesian framework to properly quantify its uncertainty across the British Isles. We find that uncertainty increases considerably for deeper Curie depths, which demonstrates that generally this method is only reliable in hotter regions, such as Scotland and Northern Ireland.
Andrzej Górszczyk, Stéphane Operto, Laure Schenini, and Yasuhiro Yamada
Solid Earth, 10, 765–784, https://doi.org/10.5194/se-10-765-2019, https://doi.org/10.5194/se-10-765-2019, 2019
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In order to broaden our knowledge about the deep lithosphere using seismic methods, we develop leading-edge imaging workflows integrating different types of data. Here we exploit the complementary information carried by seismic wavefields, which are fundamentally different in terms of acquisition setting. We cast this information into our processing workflow and build a detailed model of the subduction zone, which is subject to further geological interpretation.
Miłosz Mężyk, Michał Malinowski, and Stanisław Mazur
Solid Earth, 10, 683–696, https://doi.org/10.5194/se-10-683-2019, https://doi.org/10.5194/se-10-683-2019, 2019
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The Precambrian East European Craton is one of the most important building blocks of the European plate. Unlike in Scandinavia, its crystalline crust in Poland is concealed beneath younger sediments. Reprocessing of ca. 950 km regional reflection seismic profiles acquired during shale gas exploration in NE Poland revealed reflectivity patterns interpreted as signs of Svekofennian orogeny, proving a similar mechanism of Paleoproterozoic crustal formation across the Baltic Sea.
Anke Dannowski, Heidrun Kopp, Frauke Klingelhoefer, Dirk Klaeschen, Marc-André Gutscher, Anne Krabbenhoeft, David Dellong, Marzia Rovere, David Graindorge, Cord Papenberg, and Ingo Klaucke
Solid Earth, 10, 447–462, https://doi.org/10.5194/se-10-447-2019, https://doi.org/10.5194/se-10-447-2019, 2019
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The nature of the Ionian Sea crust has been the subject of scientific debate for more than 30 years. Seismic data, recorded on ocean bottom instruments, have been analysed and support the interpretation of the Ionian Abyssal Plain as a remnant of the Tethys oceanic lithosphere with the Malta Escarpment as a transform margin and a Tethys opening in the NNW–SSE direction.
Martin Staněk and Yves Géraud
Solid Earth, 10, 251–274, https://doi.org/10.5194/se-10-251-2019, https://doi.org/10.5194/se-10-251-2019, 2019
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Granite is suitable to host geothermal wells or disposals of hazardous waste and in these cases the rock porosity and permeability are critical. Our detailed porosity and permeability data on variously deformed Lipnice granite yield a span of 5 orders of magnitude in permeability between the least and the most deformed facies. To facilitate the estimation of porosity and permeability in similar settings, we provide optical and chemical data on the characteristic minerals of each facies.
David Marti, Ignacio Marzan, Jana Sachsenhausen, Joaquina Alvarez-Marrón, Mario Ruiz, Montse Torne, Manuela Mendes, and Ramon Carbonell
Solid Earth, 10, 177–192, https://doi.org/10.5194/se-10-177-2019, https://doi.org/10.5194/se-10-177-2019, 2019
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A detailed knowledge of the very shallow subsurface has become of crucial interest for modern society, especially if it hosts critical surface infrastructures such as temporary waste storage sites. The use of indirect methods to characterize the internal structure of the subsurface has been successfully applied, based on the 3-D distribution of seismic velocities and well-log data, which are of great interest for civil engineering companies.
Alessandro Lechmann, David Mair, Akitaka Ariga, Tomoko Ariga, Antonio Ereditato, Ryuichi Nishiyama, Ciro Pistillo, Paola Scampoli, Fritz Schlunegger, and Mykhailo Vladymyrov
Solid Earth, 9, 1517–1533, https://doi.org/10.5194/se-9-1517-2018, https://doi.org/10.5194/se-9-1517-2018, 2018
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Muon tomography is a technology, similar to X-ray tomography, to image the interior of an object, including geologically interesting ones. In this work, we examined the influence of rock composition on the physical measurements, and the possible error that is made by assuming a too-simplistic rock model. We performed numerical simulations for a more realistic rock model and found that beyond 300 m of rock, the composition starts to play a significant role and has to be accounted for.
Alireza Malehmir, Bo Bergman, Benjamin Andersson, Robert Sturk, and Mattis Johansson
Solid Earth, 9, 1469–1485, https://doi.org/10.5194/se-9-1469-2018, https://doi.org/10.5194/se-9-1469-2018, 2018
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Interest and demand for green-type energy usage and storage are growing worldwide. Among several, thermal energy storage that stores energy (excess heat or cold) in fluids is particularly interesting. For an upscaling purpose, three seismic profiles were acquired within the Tornquist suture zone in the southwest of Sweden and historical crustal-scale offshore BABEL lines revisited. A number of dykes have been imaged and implications for the storage and tectonic setting within the zone discussed.
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Short summary
Our study focuses on the correlation of two geophysical parameters (electrical resistivity and density) with geological units. We use this computer-aided correlation to improve interpretation of the Earth’s formation history along the Namibian coast and the associated formation of the South Atlantic Ocean. It helps to distinguish different types of sediment cover and varieties of oceanic crust, as well as to identify typical features associated with the breakup of continents.
Our study focuses on the correlation of two geophysical parameters (electrical resistivity and...
