Articles | Volume 8, issue 3
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Correcting for static shift of magnetotelluric data with airborne electromagnetic measurements: a case study from Rathlin Basin, Northern Ireland
Geophysics Section, School of Cosmic Physics, Dublin Institute for Advanced Studies (DIAS), 5 Merrion Square, Dublin 2, Ireland
National University of Ireland, Galway, University Road, Galway, Ireland
Geophysics Section, School of Cosmic Physics, Dublin Institute for Advanced Studies (DIAS), 5 Merrion Square, Dublin 2, Ireland
Alan G. Jones
Geophysics Section, School of Cosmic Physics, Dublin Institute for Advanced Studies (DIAS), 5 Merrion Square, Dublin 2, Ireland
Complete MT Solutions, Ottawa, Canada
Mark R. Muller
Geological Survey of Northern Ireland (GSNI), Belfast, UK
No articles found.
D. Mottaghy, G. Schwamborn, and V. Rath
Clim. Past, 9, 119–133,
Related subject area
GeophysicsSeismic amplitude response to internal heterogeneity of mass-transport depositsInvestigation of the effects of surrounding media on the distributed acoustic sensing of a helically wound fibre-optic cable with application to the New Afton deposit, British ColumbiaUtilisation of probabilistic magnetotelluric modelling to constrain magnetic data inversion: proof-of-concept and field applicationGeophysical analysis of an area affected by subsurface dissolution – case study of an inland salt marsh in northern Thuringia, GermanyComparison of straight-ray and curved-ray surface wave tomography approaches in near-surface studiesAn efficient probabilistic workflow for estimating induced earthquake parameters in 3D heterogeneous media3D deep geothermal reservoir imaging with wireline distributed acoustic sensing in two boreholesFormation and geophysical character of transitional crust at the passive continental margin around Walvis Ridge, Namibia3D high-resolution seismic imaging of the iron oxide deposits in Ludvika (Sweden) using full-waveform inversion and reverse time migrationThree-dimensional reflection seismic imaging of the iron oxide deposits in the Ludvika mining area, Sweden, using Fresnel volume migrationDrone-based magnetic and multispectral surveys to develop a 3D model for mineral exploration at Qullissat, Disko Island, GreenlandAmbient seismic noise analysis of LARGE-N data for mineral exploration in the Central Erzgebirge, GermanySurface-wave tomography for mineral exploration: a successful combination of passive and active data (Siilinjärvi phosphorus mine, Finland)Reflection tomography by depth warping: a case study across the Java trenchDynamic motion monitoring of a 3.6 km long steel rod in a borehole during cold-water injection with distributed fiber-optic sensingImpact of Timanian thrust systems on the late Neoproterozoic–Phanerozoic tectonic evolution of the Barents Sea and SvalbardForearc density structure of the overriding plate in the northern area of the giant 1960 Valdivia earthquakeImaging crustal structures through a passive seismic imaging approach in a mining area in Saxony, GermanyInvestigating the effects of intersection flow localization in equivalent-continuum-based upscaling of flow in discrete fracture networksCross-diffusion waves resulting from multiscale, multiphysics instabilities: application to earthquakesReverse time migration (RTM) imaging of iron oxide deposits in the Ludvika mining area, SwedenNear-surface structure of the Sodankylä area in Finland, obtained by passive seismic interferometryEvolution of the Iberian Massif as deduced from its crustal thickness and geometry of a mid-crustal (Conrad) discontinuityFour-dimensional tracer flow reconstruction in fractured rock through borehole ground-penetrating radar (GPR) monitoringMoho topography beneath the European Eastern Alps by global-phase seismic interferometrySeismic imaging across fault systems in the Abitibi greenstone belt – an analysis of pre- and post-stack migration approaches in the Chibougamau area, Quebec, CanadaEarly Cenozoic Eurekan strain partitioning and decoupling in central Spitsbergen, SvalbardOn the comparison of strain measurements from fibre optics with a dense seismometer array at Etna volcano (Italy)Cross-diffusion waves resulting from multiscale, multi-physics instabilities: theoryMulti-scale analysis and modelling of aeromagnetic data over the Bétaré-Oya area in eastern Cameroon, for structural evidence investigationsThe impact of seismic interpretation methods on the analysis of faults: a case study from the Snøhvit field, Barents SeaWireline distributed acoustic sensing allows 4.2 km deep vertical seismic profiling of the Rotliegend 150 °C geothermal reservoir in the North German BasinIntegrated land and water-borne geophysical surveys shed light on the sudden drying of large karst lakes in southern MexicoSparse 3D reflection seismic survey for deep-targeting iron oxide deposits and their host rocks, Ludvika Mines, SwedenFault sealing and caprock integrity for CO2 storage: an in situ injection experimentWhat can seismic noise tell us about the Alpine reactivation of the Iberian Massif? An example in the Iberian Central SystemIn situ hydromechanical responses during well drilling recorded by fiber-optic distributed strain sensingCoherent diffraction imaging for enhanced fault and fracture network characterizationOn the morphology and amplitude of 2D and 3D thermal anomalies induced by buoyancy-driven flow within and around fault zonesCharacterizing a decametre-scale granitic reservoir using ground-penetrating radar and seismic methodsMantle flow below the central and greater Alpine region: insights from SKS anisotropy analysis at AlpArray and permanent stationsUpper Jurassic carbonate buildups in the Miechów Trough, southern Poland – insights from seismic data interpretationsSeismic evidence for failed rifting in the Ligurian Basin, Western Alpine domainAzimuth-, angle- and frequency-dependent seismic velocities of cracked rocks due to squirt flowCharacteristics of a fracture network surrounding a hydrothermally altered shear zone from geophysical borehole logsBayesian full-waveform inversion of tube waves to estimate fracture aperture and complianceCorrelation of core and downhole seismic velocities in high-pressure metamorphic rocks: a case study for the COSC-1 borehole, SwedenNew regional stratigraphic insights from a 3D geological model of the Nasia sub-basin, Ghana, developed for hydrogeological purposes and based on reprocessed B-field data originally collected for mineral explorationThe relative contributions of scattering and viscoelasticity to the attenuation of S waves in Earth's mantleCharacterisation of subglacial water using a constrained transdimensional Bayesian transient electromagnetic inversion
Jonathan Ford, Angelo Camerlenghi, Francesca Zolezzi, and Marilena Calarco
Solid Earth, 14, 137–151,Short summary
Submarine landslides commonly appear as low-amplitude zones in seismic data. Previous studies have attributed this to a lack of preserved internal structure. We use seismic modelling to show that an amplitude reduction can be generated even when there is still metre-scale internal structure, by simply deforming the bedding. This has implications for interpreting failure type, for core-seismic correlation and for discriminating landslides from other "transparent" phenomena such as free gas.
Sepidehalsadat Hendi, Mostafa Gorjian, Gilles Bellefleur, Christopher D. Hawkes, and Don White
Solid Earth, 14, 89–99,Short summary
In this study, the modelling results are used to help understand the performance of a helically wound fibre (HWC) from a field study at the New Afton mine, British Columbia. We introduce the numerical 3D model to model strain values in HWC to design more effective HWC system. The DAS dataset at New Afton, interpreted in the context of our modelling, serves as a practical demonstration of the extreme effects of surrounding media and coupling on HWC data quality.
Jérémie Giraud, Hoël Seillé, Mark D. Lindsay, Gerhard Visser, Vitaliy Ogarko, and Mark W. Jessell
Solid Earth, 14, 43–68,Short summary
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.
Sonja H. Wadas, Hermann Buness, Raphael Rochlitz, Peter Skiba, Thomas Günther, Michael Grinat, David C. Tanner, Ulrich Polom, Gerald Gabriel, and Charlotte M. Krawczyk
Solid Earth, 13, 1673–1696,Short summary
The dissolution of rocks poses a severe hazard because it can cause subsidence and sinkhole formation. Based on results from our study area in Thuringia, Germany, using P- and SH-wave reflection seismics, electrical resistivity and electromagnetic methods, and gravimetry, we develop a geophysical investigation workflow. This workflow enables identifying the initial triggers of subsurface dissolution and its control factors, such as structural constraints, fluid pathways, and mass movement.
Mohammadkarim Karimpour, Evert Slob, and Laura Valentina Socco
Solid Earth, 13, 1569–1583,Short summary
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.
La Ode Marzujriban Masfara, Thomas Cullison, and Cornelis Weemstra
Solid Earth, 13, 1309–1325,Short summary
Induced earthquakes are natural phenomena in which the events are associated with human activities. Although the magnitudes of these events are mostly smaller than tectonic events, in some cases, the magnitudes can be high enough to damage buildings near the event's location. To study these (high-magnitude) induced events, we developed a workflow in which the recorded data from an earthquake are used to describe the source and monitor the area for other (potentially high-magnitude) earthquakes.
Evgeniia Martuganova, Manfred Stiller, Ben Norden, Jan Henninges, and Charlotte M. Krawczyk
Solid Earth, 13, 1291–1307,Short summary
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.
Gesa Franz, Marion Jegen, Max Moorkamp, Christian Berndt, and Wolfgang Rabbel
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 breaking-apart of continents.
Brij Singh, Michał Malinowski, Andrzej Górszczyk, Alireza Malehmir, Stefan Buske, Łukasz Sito, and Paul Marsden
Solid Earth, 13, 1065–1085,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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.
Yueyang Xia, Dirk Klaeschen, Heidrun Kopp, and Michael Schnabel
Solid Earth, 13, 367–392,Short summary
Geological interpretations based on seismic depth images depend on an accurate subsurface velocity model. Reflection tomography is one method to iteratively update a velocity model based on depth error analysis. We used a warping method to estimate closely spaced data-driven depth error displacement fields. The application to a multichannel seismic line across the Sunda subduction zone illustrates the approach which leads to more accurate images of complex geological structures.
Martin Peter Lipus, Felix Schölderle, Thomas Reinsch, Christopher Wollin, Charlotte Krawczyk, Daniela Pfrang, and Kai Zosseder
Solid Earth, 13, 161–176,Short summary
A fiber-optic cable was installed along a freely suspended rod in a deep geothermal well in Munich, Germany. A cold-water injection test was monitored with fiber-optic distributed acoustic and temperature sensing. During injection, we observe vibrational events in the lower part of the well. On the basis of a mechanical model, we conclude that the vibrational events are caused by thermal contraction of the rod. The results illustrate potential artifacts when analyzing downhole acoustic data.
Jean-Baptiste P. Koehl, Craig Magee, and Ingrid M. Anell
Solid Earth, 13, 85–115,Short summary
The present study shows evidence of fault systems (large cracks in the Earth's crust) hundreds to thousands of kilometers long and several kilometers thick extending from northwestern Russia to the northern Norwegian Barents Sea and the Svalbard Archipelago using seismic, magnetic, and gravimetric data. The study suggests that the crust in Svalbard and the Barents Sea was already attached to Norway and Russia at ca. 650–550 Ma, thus challenging existing models.
Andrei Maksymowicz, Daniela Montecinos-Cuadros, Daniel Díaz, María José Segovia, and Tomás Reyes
Solid Earth, 13, 117–136,Short summary
This work analyses the density structure of the continental forearc in the northern segment of the 1960 Mw 9.6 Valdivia earthquake. Results show a segmentation of the continental wedge along and perpendicular to the margin. The extension of the less rigid basement units conforming the marine wedge and Coastal Cordillera domain could modify the process of stress loading during the interseismic periods. This analysis highlights the role of the overriding plate on the seismotectonic process.
Hossein Hassani, Felix Hloušek, Stefan Buske, and Olaf Wallner
Solid Earth, 12, 2703–2715,Short summary
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.
Maximilian O. Kottwitz, Anton A. Popov, Steffen Abe, and Boris J. P. Kaus
Solid Earth, 12, 2235–2254,Short summary
Upscaling fluid flow in fractured reservoirs is an important practice in subsurface resource utilization. In this study, we first conduct numerical simulations of direct fluid flow at locations where fractures intersect to analyze the arising hydraulic complexities. Next, we develop a model that integrates these effects into larger-scale continuum models of fracture networks to investigate their impact on the upscaling. For intensively fractured systems, these effects become important.
Klaus Regenauer-Lieb, Manman Hu, Christoph Schrank, Xiao Chen, Santiago Peña Clavijo, Ulrich Kelka, Ali Karrech, Oliver Gaede, Tomasz Blach, Hamid Roshan, Antoine B. Jacquey, Piotr Szymczak, and Qingpei Sun
Solid Earth, 12, 1829–1849,Short summary
This paper presents a trans-disciplinary approach bridging the gap between observations of instabilities from the molecular scale to the very large scale. We show that all scales communicate via propagation of volumetric deformation waves. Similar phenomena are encountered in quantum optics where wave collisions can release sporadic bursts of light. Ocean waves show a similar phenomenon of rogue waves that seem to come from nowhere. This mechanism is proposed to be the trigger for earthquakes.
Yinshuai Ding and Alireza Malehmir
Solid Earth, 12, 1707–1718,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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.
Jean-Baptiste P. Koehl
Solid Earth, 12, 1025–1049,Short summary
By using seismic data and fieldwork, this contribution shows that soft, coal-rich sedimentary rocks absorbed most of early Cenozoic, Eurekan, contractional deformation in central Spitsbergen, thus suggesting that no contractional deformation event is needed in the Late Devonian to explain the deformation differences among late Paleozoic sedimentary rocks. It also shows that the Billefjorden Fault Zone, a major crack in the Earth's crust in Svalbard, is probably segmented.
Gilda Currenti, Philippe Jousset, Rosalba Napoli, Charlotte Krawczyk, and Michael Weber
Solid Earth, 12, 993–1003,Short summary
We investigate the capability of distributed acoustic sensing (DAS) to record dynamic strain changes related to Etna volcano activity in 2019. To validate the DAS measurements, we compute strain estimates from seismic signals recorded by a dense broadband array. A general good agreement is found between array-derived strain and DAS measurements along the fibre optic cable. Localised short wavelength discrepancies highlight small-scale structural heterogeneities in the investigated area.
Klaus Regenauer-Lieb, Manman Hu, Christoph Schrank, Xiao Chen, Santiago Peña Clavijo, Ulrich Kelka, Ali Karrech, Oliver Gaede, Tomasz Blach, Hamid Roshan, and Antoine B. Jacquey
Solid Earth, 12, 869–883,Short summary
In this paper we expand on a recent discovery of slow cross-diffusion hydromechanical waves cast into a new concise reaction–diffusion equation for THMC coupling. If waves are excited through the THMC reaction terms unbounded reactions can be captured by inclusion of statistical information from the lower scale through nonlocal reaction–diffusion equations. These cross-diffusion coefficients regularize extreme earthquake-like events (rogue waves) through a new form of quasi-soliton wave.
Christian Emile Nyaban, Théophile Ndougsa-Mbarga, Marcelin Bikoro-Bi-Alou, Stella Amina Manekeng Tadjouteu, and Stephane Patrick Assembe
Solid Earth, 12, 785–800,Short summary
A multi-scale analysis of aeromagnetic data combining tilt derivative, Euler deconvolution, upward continuation, and 2.75D modelling was applied over Cameroon between the latitudes 5°30'–6° N and the longitudes 13°30'–14°45' E. Major families of faults oriented ENE–WSW, E–W, NW–SE, and N–S with a NE–SW prevalence were mapped. Depths of interpreted faults range from 1000 to 3400 m, mylonitic veins were identified, and 2.75D modelling revealed fault depths greater than 1200 m.
Jennifer E. Cunningham, Nestor Cardozo, Chris Townsend, and Richard H. T. Callow
Solid Earth, 12, 741–764,Short summary
This work investigates the impact of commonly used seismic interpretation methods on the analysis of faults. Fault analysis refers to fault length, displacement, and the impact these factors have on geological modelling and hydrocarbon volume calculation workflows. This research was conducted to give geoscientists a better understanding of the importance of interpretation methods and the impact of unsuitable methology on geological analyses.
Jan Henninges, Evgeniia Martuganova, Manfred Stiller, Ben Norden, and Charlotte M. Krawczyk
Solid Earth, 12, 521–537,Short summary
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.
Matthias Bücker, Adrián Flores Orozco, Jakob Gallistl, Matthias Steiner, Lukas Aigner, Johannes Hoppenbrock, Ruth Glebe, Wendy Morales Barrera, Carlos Pita de la Paz, César Emilio García García, José Alberto Razo Pérez, Johannes Buckel, Andreas Hördt, Antje Schwalb, and Liseth Pérez
Solid Earth, 12, 439–461,Short summary
We use seismic, electromagnetic, and geoelectrical methods to assess sediment thickness and lake-bottom geology of two karst lakes. An unexpected drainage event provided us with the unusual opportunity to compare water-borne measurements with measurements carried out on the dry lake floor. The resulting data set does not only provide insight into the specific lake-bottom geology of the studied lakes but also evidences the potential and limitations of the employed field methods.
Alireza Malehmir, Magdalena Markovic, Paul Marsden, Alba Gil, Stefan Buske, Lukasz Sito, Emma Bäckström, Martiya Sadeghi, and Stefan Luth
Solid Earth, 12, 483–502,Short summary
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,Short summary
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,
Yi Zhang, Xinglin Lei, Tsutomu Hashimoto, and Ziqiu Xue
Solid Earth, 11, 2487–2497,Short summary
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,Short summary
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.
Laurent Guillou-Frottier, Hugo Duwiquet, Gaëtan Launay, Audrey Taillefer, Vincent Roche, and Gaétan Link
Solid Earth, 11, 1571–1595,Short summary
In the first kilometers of the subsurface, temperature anomalies due to heat conduction rarely exceed 20–30°C. However, when deep hot fluids in the shallow crust flow upwards, for example through permeable fault zones, hydrothermal convection can form high-temperature geothermal reservoirs. Numerical modeling of hydrothermal convection shows that vertical fault zones may host funnel-shaped, kilometer-sized geothermal reservoirs whose exploitation would not need drilling at depths below 2–3 km.
Joseph Doetsch, Hannes Krietsch, Cedric Schmelzbach, Mohammadreza Jalali, Valentin Gischig, Linus Villiger, Florian Amann, and Hansruedi Maurer
Solid Earth, 11, 1441–1455,
Laura Petrescu, Silvia Pondrelli, Simone Salimbeni, Manuele Faccenda, and the AlpArray Working Group
Solid Earth, 11, 1275–1290,Short summary
To place constraints on the mantle deformation beneath the Central Alps and the greater Alpine region, we analysed the appropriate seismic signal recorded by more than 100 stations, belonging to AlpArray and to other permanent networks. We took a picture of the imprinting that Alpine orogen history and related subductions left at depth, with a mainly orogen-parallel mantle deformation from Western Alps to Eastern Alps, but also N to S from the Po Plain to the Rhine Graben.
Łukasz Słonka and Piotr Krzywiec
Solid Earth, 11, 1097–1119,Short summary
This paper shows the results of seismic interpretations that document the presence of large Upper Jurassic carbonate buildups in the Miechów Trough (S Poland). Our work fills the gap in recognition of the Upper Jurassic carbonate depositional system of southern Poland. The results also provide an excellent generic reference point, showing how and to what extent seismic data can be used for studies of carbonate depositional systems, in particular for the identification of the carbonate buildups.
Anke Dannowski, Heidrun Kopp, Ingo Grevemeyer, Dietrich Lange, Martin Thorwart, Jörg Bialas, and Martin Wollatz-Vogt
Solid Earth, 11, 873–887,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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.
Elikplim Abla Dzikunoo, Giulio Vignoli, Flemming Jørgensen, Sandow Mark Yidana, and Bruce Banoeng-Yakubo
Solid Earth, 11, 349–361,Short summary
Time-domain electromagnetic (TEM) geophysics data originally collected for mining purposes were reprocessed and inverted. The new inversions were used to construct a 3D model of the subsurface geology to facilitate hydrogeological investigations within a DANIDA-funded project. Improved resolutions from the TEM enabled the identification of possible paleovalleys of glacial origin, suggesting the need for a reevaluation of the current lithostratigraphy of the Voltaian sedimentary basin.
Susini deSilva and Vernon F. Cormier
Solid Earth, 11, 161–171,Short summary
Seismic waves attenuate with distance due to two effects: (1) removal of energy by internal friction and (2) redistribution of energy into different distances and time windows by scattering from heterogeneous Earth structure. The relative contribution of these two effects is estimated by synthesizing seismograms having varying amounts of internal friction and heterogeneities. The attenuation of observed S waveforms requires contributions from both internal friction and scattering.
Siobhan F. Killingbeck, Adam D. Booth, Philip W. Livermore, C. Richard Bates, and Landis J. West
Solid Earth, 11, 75–94,Short summary
This paper presents MuLTI-TEM, a Bayesian inversion tool for inverting TEM data with independent depth constraints to provide statistical properties and uncertainty analysis of the resistivity profile with depth. MuLTI-TEM is highly versatile, being compatible with most TEM survey designs, ground-based or airborne, along with the depth constraints being provided from any external source. Here, we present an application of MuLTI-TEM to characterise the subglacial water under a Norwegian glacier.
Archie, G. E.: Electrical Resistivity an Aid in Core-Analysis Interpretation, AAPG Bulletin, 31, 350–366, https://doi.org/10.1306/3d93395c-16b1-11d7-8645000102c1865d, 1947.
Auken, E., Vest Christiansen, A., Kirkegaard, C., Fiandaca, G., Schamper, C., Behroozmand, A. A., Binley, A., Nielsen, E., Effersø, F., Christensen, N. B., Sørensen, K., Foged, N., and Vignoli, G.: An overview of a highly versatile forward and stable inverse algorithm for airborne, ground-based and borehole electromagnetic and electric data, Explor. Geophys., 46, 223–235, https://doi.org/10.1071/EG13097, 2014.
Avdeeva, A., Moorkamp, M., Avdeev, D., Jegen, M., and Miensopust, M.: Three-dimensional inversion of magnetotelluric impedance tensor data and full distortion matrix, Geophys. J. Int., 202, 464–481, https://doi.org/10.1093/gji/ggv144, 2015.
Beamish, D.: The bedrock electrical conductivity structure of Northern Ireland, Geophys. J. Int., 194, 683–699, https://doi.org/10.1093/gji/ggt073, 2013.
Beamish, D., Cuss, R. J., Lahti, M., Scheib, C., and Tartaras, E.: The Tellus Airborne Geophysical Survey of Northern Ireland: Final Processing Report, Internal Report IR/06/136, British Geological Survey, Nottingham, UK, 2006.
Bean, C. J. and Martini, F.: Sub-basalt seismic imaging using optical-to-acoustic model building and wave equation datuming processing, Mar. Petrol. Geol., 27, 555–562, https://doi.org/10.1016/j.marpetgeo.2009.09.007, 2010.
Berdichevsky, M.: Methods used in the U.S.S.R. to reduce near-surface inhomogeneity effects on deep magnetotelluric sounding, Phys. Earth Planet. In., 53, 194–206, https://doi.org/10.1016/0031-9201(89)90003-4, 1989.
Berdichevsky, M. N. and Dmitriev, V. I.: Models and Methods of Magnetotellurics, Springer, Berlin-Heidelberg, Germany, 2008.
Bernabe, Y., Mok, U., and Evans, B.: Permeability-porosity Relationships in Rocks Subjected to Various Evolution Processes, Pure Appl. Geophys., 160, 937–960, 2003.
Bjørlykke, K.: Petroleum Geoscience: From Sedimentary Environments to Rock Physics, Springer, Berlin-Heidelberg, Germany, 2010.
Burd, A. I., Booker, J. R., Mackie, R., Favetto, A., and Pomposiello, M. C.: Three-dimensional electrical conductivity in the mantle beneath the Payún Matrú Volcanic Field in the Andean backarc of Argentina near 36.5° S: evidence for decapitation of a mantle plume by resurgent upper mantle shear during slab steepening, Geophys. J. Int., 198, 812–827, https://doi.org/10.1093/gji/ggu145, 2014.
Chave, A. D. and Jones, A. G.: Electric and Magnetic Field Galvanic Distortion Decomposition of BC87 Data, J. Geomagn. Geoelectr., 49, 767–789, https://doi.org/10.5636/jgg.49.767, 1997.
Chave, A. D. and Jones, A. G.: The Magnetotelluric Method: Theory and Practice, Cambridge University Press, Cambridge, UK, https://doi.org/10.1017/cbo9781139020138, 2012.
Chave, A. D. and Smith, J. T.: On electric and magnetic galvanic distortion tensor decompositions, J. Geophys. Res., 99, 4669–4682, https://doi.org/10.1029/93jb03368, 1994.
Colombo, D., Keho, T., Janoubi, E., and Soyer, W.: Sub-basalt imaging with broadband magnetotellurics in NW Saudi Arabia, in: Expanded Abstracts of the SEG San Antonio 2011 Annual Meeting, 18–23 September 2011, in San Antonio, Texas, vol. 619–623, 2011.
Crowe, M., Heinson, G., and Dhu, T.: Magnetotellurics and airborne electromagnetics – a combined method for assessing basin structure and exploring for unconformity-related uranium, ASEG Extended Abstracts 2013: 23rd Geophysical Conference, 11–14 August 2013, in Melbourne, Australia, 1–5, https://doi.org/10.1071/ASEG2013ab225, 2013.
DeGroot-Hedlin, C.: Inversion for regional 2-D resistivity structure in the presence of galvanic scatterers, Geophys. J. Int., 122, 877–888, https://doi.org/10.1111/j.1365-246X.1995.tb06843.x, 1995.
De Groot-Hedlin, C. D.: Removal of static shift in two dimensions by regularized inversion, Geophysics, 56, 2102–2106, https://doi.org/10.1190/1.1443022, 1991.
Egbert, G. D. and Kelbert, A.: Computational recipes for electromagnetic inverse problems, Geophys. J. Int., 189, 251–267, https://doi.org/10.1111/j.1365-246x.2011.05347.x, 2012.
Gallardo, L. A. and Meju, M. A.: Characterization of heterogeneous near-surface materials by joint 2-D inversion of dc resistivity and seismic data, Geophys. Res. Lett., 30, 1658, https://doi.org/10.1029/2003GL017370, 2003.
Gamble, T. D.: Magnetotellurics with a remote magnetic reference, Geophysics, 44, 53–68, https://doi.org/10.1190/1.1440923, 1979.
Gamble, T. D., Goubau, W. M., and Clarke, J.: Error analysis for remote reference magnetotellurics, Geophysics, 44, 959–968, https://doi.org/10.1190/1.1440988, 1979.
Gibson, P. J.: Geophysical Characteristics of the Tow Valley Fault Zone in North-East Ireland, Irish J. Earth Sci., 22, 1–13, 2004.
Glover, P. W. J.: A generalized Archie's law for n phases, Geophysics, 75, E247–E265, https://doi.org/10.1190/1.3509781, 2010.
Goodman, R., Jones, G. L. I., Kelly, J., Slower, E., and O'Neill, N.: Geothermal Energy Resource Map of Ireland, Final Report, Tech. rep., Sustainable Energy Authority of Ireland, Dublin, Ireland, 2004.
Guéguen, Y. and Palciauskas, V.: Introduction to the physics of rocks, Princeton University Press, New Jersey, USA, 1994.
Hautot, S., Single, R. T., Watson, J., Harrop, N., Jerram, D. A., Tarits, P., Whaler, K., and Dawes, G.: 3-D magnetotelluric inversion and model validation with gravity data for the investigation of flood basalts and associated volcanic rifted margins, Geophys. J. Int., 170, 1418–1430, https://doi.org/10.1111/j.1365-246X.2007.03453.x, 2007.
Heincke, B., Jegen, M., Moorkamp, M., and Hobbs, R. W.: Joint-inversion of magnetotelluric, gravity and seismic data to image sub-basalt sediments offshore the Faroe-Islands, SEG Technical Program Expanded Abstracts, 2014, 770–775, https://doi.org/10.1190/segam2014-1401.1, 2014.
Hepworth, C. and Sanders, I. S. (Eds.): The Geology of Ireland: Second Edition, Dunedin Academic Press Ltd., 2 Edn., 2009.
Jegen, M. D., Hobbs, R. W., Tarits, P., and Chave, A.: Joint inversion of marine magnetotelluric and gravity data incorporating seismic constraints. Preliminary results of sub-basalt imaging off the Faroe Shelf, Earth Planet. Sci. Lett., 282, 47–55, 2009.
Jones, A. and Jödicke, H.: Magnetotelluric transfer function estimation improvement by a coherence-based rejection technique, in: SEG Technical Program Expanded Abstracts 1984, SEG Technical Program Expanded Abstracts, Society of Exploration Geophysicists, 51–55, https://doi.org/10.1190/1.1894081, 1984.
Jones, A. G.: Static shift of magnetotelluric data and its removal in a sedimentary basin environment, Geophysics, 53, 967–978, https://doi.org/10.1190/1.1442533, 1988.
Jones, A. G.: Electrical properties of the lower continental crust, in: Continental Lower Crust, vol. 23, 81–143, Elsevier Amsterdam, the Netherlands, 1992.
Jones, A. G.: Electromagnetic interrogation of the anisotropic Earth: Looking into the Earth with polarized spectacles, Phys. Earth Planet. In., 158, 281–291, https://doi.org/10.1016/j.pepi.2006.03.026, 2006.
Jones, A. G.: Three-dimensional galvanic distortion of three-dimensional regional conductivity structures: Comment on “Three-dimensional joint inversion for magnetotelluric resistivity and static shift distributions in complex media” by Yutaka Sasaki and Max A. Meju, J. Geophys. Res., 116, B12104+, https://doi.org/10.1029/2011jb008665, 2011.
Jones, A. G.: Distortion of magnetotelluric data: its identification and removal, Cambridge University Press, https://doi.org/10.1017/cbo9781139020138, 2012.
Jones, A. G., Chave, A. D., Egbert, G., Auld, D., and Bahr, K.: A Comparison of Techniques for Magnetotelluric Response Function Estimation, J. Geophys. Res., 94, 14201–14213, https://doi.org/10.1029/jb094ib10p14201, 1989.
Jupp, D. L. B. and Vozoff, K.: Stable Iterative Methods for the Inversion of Geophysical Data, Geophys. J. Roy. Astr. S., 42, 957–976, 1975.
Kaufman, Alekseev, D., and Oristaglio, M.: Principles of Electromagnetic Methods in Surface Geophysics, Elsevier, Amsterdam, the Netherlands, 2014.
Kelbert, A., Meqbel, N., Egbert, G. D., and Tandon, K.: ModEM: A modular system for inversion of electromagnetic geophysical data, Comput. Geosci., 66, 40–53, https://doi.org/10.1016/j.cageo.2014.01.010, 2014.
Keller, G. V. and Frischknecht, F. C.: Electrical methods in geophysical prospecting, Pergamon Press, Oxford, UK, 1966.
Leväniemi, H., Beamish, D., Hautaniemi, H., Kurimo, M., Suppala, I., Vironmäki, J., Cuss, R. J., Lahti, M., and Tartaras, E.: The JAC airborne EM system: AEM-05, J. Appl. Geophys., 67, 219–233, https://doi.org/10.1016/j.jappgeo.2007.10.001, 2009.
Luijendijk, E. and Gleeson, T.: How well can we predict permeability in sedimentary basins? Deriving and evaluating porosity-permeability equations for noncemented sand and clay mixtures, Geofluids, 15, 67–83, https://doi.org/10.1111/gfl.12115, 2015.
Martini, F., Hobbs, W. W., Bean, C. J., and Single, R.: A complex 3-D volume for sub-basalt imaging, First Break, 23, 41–51, 2005.
Mavko, G., Mukerji, T., and Dvorkin, J.: The Rock Physics Handbook. Tools for Seismic Modelling of Porous Media, Cambridge University Press, Cambridge, UK, 2009.
McNeice, G. W. and Jones, A. G.: Multisite, multifrequency tensor decomposition of magnetotelluric data, Geophysics, 66, 158–173, https://doi.org/10.1190/1.1444891, 2001.
Miensopust, M. P.: Multidimensional Magnetotellurics. A 2-D case study and a 3-D approach to simultaneously invert for resistivity structure and distortion parameters, PhD thesis, Faculty of Science, National University of Ireland, Galway, Ireland, 2010.
Miensopust, M. P., Jones, A. G., Hersir, G. P., and Vilhjálmsson, A. M.: The Eyjafjallajökull volcanic system, Iceland: insights from electromagnetic measurements, Geophys. J. Int., 199, 1187–1204, https://doi.org/10.1093/gji/ggu322, 2014.
Minsley, B. J.: A trans-dimensional Bayesian Markov chain Monte Carlo algorithm for model assessment using frequency-domain electromagnetic data, Geophys. J. Int., 187, 252–272, https://doi.org/10.1111/j.1365-246x.2011.05165.x, 2011.
Mitchell, W. I.: The Geology of Northern Ireland: Our Natural Foundation, Geological Survey of Northern Ireland, Belfast, UK, 2004.
Muñoz, G.: Exploring for Geothermal Resources with Electromagnetic Methods, Surv. Geophys., 35, 101–122, https://doi.org/10.1007/s10712-013-9236-0, 2014.
Naylor, D. and Shannon, P.: Petroleum geology of Ireland, Dunedin Academic Press Ltd, Edinburgh, UK, 2011.
Nover, G.: Electrical Properties of Crustal and Mantle Rocks – A Review of Laboratory Measurements and their Explanation, Surv. Geophys., 26, 593–651, https://doi.org/10.1007/s10712-005-1759-6, 2005.
Pape, H., Clauser, C., and Iffland, J.: Permeability prediction based on fractal pore-space geometry, Geophysics, 64, 1447–1460, 1999.
Pape, H., Clauser, C., and Iffland, J.: Variation of Permeability with Porosity in Sandstone Diagenesis Interpreted with a Fractal Pore space Model, Pure Appl. Geophys., 157, 603–619, 2000.
Pasquali, R., O'Neill, N., Reay, D., and Waugh, T.: The geothermal potential of Northern Ireland, in: Proceedings World Geothermal Congress, 25–30 April 2010 in Bali, Indonesia, 2010.
Pellerin, L. D. and Hohmann, G. W.: Transient electromagnetic inversion; a remedy for magnetotelluric static shifts, Geophysics, 55, 1242–1250, https://doi.org/10.1190/1.1442940, 1990.
Poll, H. E., Weaver, J. T., and Jones, A. G.: Calculations of voltages for magnetotelluric modeling of a region with near-surface inhomogeneities, Phys. Earth Planet. Inter., 53, 287–297, 1989.
Raffensperger, J. P.: Numerical simulation of basin-scale hydrochemical processes, in: Advances in Porous Media, edited by: Corapcioglu, M. Y., vol. 3, 185–305, Elsevier, New York, USA, 1996.
Raiche, A.: A flow-through Hankel transform technique for rapid, accurate Green's function computation, Radio Sci., 34, 549–555, https://doi.org/10.1029/1998rs900037, 1999.
Raiche, A. P., Jupp, D. L. B., Rutter, H., and Vozoff, K.: The joint use of coincident loop transient electromagnetic and Schlumberger sounding to resolve layered structures, Geophysics, 50, 1618–1627, https://doi.org/10.1190/1.1441851, 1985.
Reay, D. and Kelly, J.: Deep Geothermal Energy Resource Potential in Northern Ireland, European Geologist, 29, 14–18, 2010.
Rosenkjaer, G. K., Gasperikova, E., Newman, G. A., Arnason, K., and Lindsey, N. J.: Comparison of 3-D MT inversions for geothermal exploration: Case studies for Krafla and Hengill geothermal systems in Iceland, Geothermics, 57, 258–274, 2015.
Rousseeuw, P. J.: Least Median of Squares Regression, J. Am. Stat. Assoc., 79, 871–880, https://doi.org/10.1080/01621459.1984.10477105, 1984.
Rousseeuw, P. J. and Leroy, A. M.: Robust Regression and Outlier Detection, Wiley-Interscience, 1 Edn., 2003.
Sasaki, Y. and Meju, M. A.: Three-dimensional joint inversion for magnetotelluric resistivity and static shift distributions in complex media, J. Geophys. Res., 111, B05101, https://doi.org/10.1029/2005JB004009, 2006.
Schnaidt, S. and Heinson, G.: Bootstrap resampling as a tool for uncertainty analysis in 2-D magnetotelluric inversion modelling, Geophys. J. Int., 203, 92–106, 2015.
Simpson, F. and Bahr, K.: Practical Magnetotellurics, Cambridge University Press, Cambridge, UK, 2005.
Sternberg, B. K., Washburne, J. C., and Pellerin, L.: Correction for the static shift in magnetotellurics using transient electromagnetic soundings, Geophysics, 53, 1459–1468, https://doi.org/10.1190/1.1442426, 1988.
Torres-Verdin, C. and Bostick, F. X.: Principles of spatial surface electric field filtering in magnetotellurics; electromagnetic array profiling (EMAP), Geophysics, 57, 603–622, https://doi.org/10.1190/1.1443273, 1992.
Ward, S. H. and Hohmann, G. W.: Electromagnetic Methods in Applied Geophysics, Tulsa, Oklahoma, USA, vol. 1, Theory, 131–312, 1988.
Wight, D. and Bostick, F. X.: Cascade decimation – A technique for real time estimation of power spectra, in: Acoustics, Speech, and Signal Processing, Acoustics, Speech, and Signal Processing, IEEE International Conference on ICASSP '80, 9–11 April 1980, Denver, Colorado, USA, vol. 5, 626–629, IEEE, https://doi.org/10.1109/icassp.1980.1170868, 1980.
Wilson, H. E. and Manning, P. I.: Geology of the Causeway Coast, British Geological Survey, Nottingham, UK, 1978.
Zinszner, B. and Pellerin, F. M.: A Geoscientist's Guide to Petrophysics, Editions Technip, Paris, France, 2007.
We have modelled airborne electromagnetic data in order to correct bias in magnetotelluric data caused by very near-surface resistivity variations. Doing so recovers structures that match boreholes in the area more closely. This research is part of an exploration project looking at geothermal resources, and improved accuracy in modelling translates directly to more confidence in resources assessments.
We have modelled airborne electromagnetic data in order to correct bias in magnetotelluric data...