Articles | Volume 2, issue 2
https://doi.org/10.5194/se-2-315-2011
© Author(s) 2011. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/se-2-315-2011
© Author(s) 2011. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
19 Dec 2011
Research article |
| 19 Dec 2011
Influence of the Ringwoodite-Perovskite transition on mantle convection in spherical geometry as a function of Clapeyron slope and Rayleigh number
M. Wolstencroft
now at: University of Ottawa, Ottawa, Ontario, Canada
School of Earth and Ocean Sciences, Cardiff University, Main Building, Park Place, Cardiff, Wales, CF10 3AT, UK
J. H. Davies
School of Earth and Ocean Sciences, Cardiff University, Main Building, Park Place, Cardiff, Wales, CF10 3AT, UK
Related subject area
Geodynamics
Influence of heterogeneous thermal conductivity on the long-term evolution of the lower-mantle thermochemical structure: implications for primordial reservoirs
Transport mechanisms of hydrothermal convection in faulted tight sandstones
The role of edge-driven convection in the generation ofvolcanism – Part 2: Interaction with mantle plumes, applied to the Canary Islands
The effect of low-viscosity sediments on the dynamics and accretionary style of subduction margins
Thermal non-equilibrium of porous flow in a resting matrix applicable to melt migration: a parametric study
101 geodynamic modelling: how to design, interpret, and communicate numerical studies of the solid Earth
Crustal structure of the Volgo–Uralian subcraton revealed by inverse and forward gravity modelling
Plume-ridge interactions: Ridge suction versus plate drag
On the choice of finite element for applications in geodynamics
A new finite element approach to model microscale strain localization within olivine aggregates
Interpolation of magnetic anomalies over an oceanic ridge region using an equivalent source technique and crust age model constraint
Coupled dynamics and evolution of primordial and recycled heterogeneity in Earth's lower mantle
Buoyancy versus shear forces in building orogenic wedges
Comparing global seismic tomography models using varimax principal component analysis
Magma ascent mechanisms in the transition regime from solitary porosity waves to diapirism
Analytical solution for residual stress and strain preserved in anisotropic inclusion entrapped in an isotropic host
Numerical solutions of the flexure equation
Gravity effect of Alpine slab segments based on geophysical and petrological modelling
The role of edge-driven convection in the generation of volcanism – Part 1: A 2D systematic study
Gravity modeling of the Alpine lithosphere affected by magmatism based on seismic tomography
Timescales of chemical equilibrium between the convecting solid mantle and over- and underlying magma oceans
The preserved plume of the Caribbean Large Igneous Plateau revealed by 3D data-integrative models
Impact of upper mantle convection on lithosphere hyperextension and subsequent horizontally forced subduction initiation
Pragmatic solvers for 3D Stokes and elasticity problems with heterogeneous coefficients: evaluating modern incomplete LDLT preconditioners
Combined numerical and experimental study of microstructure and permeability in porous granular media
Mapping undercover: integrated geoscientific interpretation and 3D modelling of a Proterozoic basin
Monitoring crustal CO2 flow: methods and their applications to the mofettes in West Bohemia
On the self-regulating effect of grain size evolution in mantle convection models: application to thermochemical piles
Deciphering the metamorphic evolution of the Pulo do Lobo metasedimentary domain (SW Iberian Variscides)
The impact of rheological uncertainty on dynamic topography predictions
The effect of effective rock viscosity on 2-D magmatic porosity waves
Density distribution across the Alpine lithosphere constrained by 3-D gravity modelling and relation to seismicity and deformation
Pore-scale permeability prediction for Newtonian and non-Newtonian fluids
3-D crustal density model of the Sea of Marmara
Oblique rifting: the rule, not the exception
GHOST: Geoscientific Hollow Sphere Tessellation
A high-resolution lithospheric magnetic field model over southern Africa based on a joint inversion of CHAMP, Swarm, WDMAM, and ground magnetic field data
Mechanical models to estimate the paleostress state from igneous intrusions
Density structure and isostasy of the lithosphere in Egypt and their relation to seismicity
The effect of obliquity on temperature in subduction zones: insights from 3-D numerical modeling
Effects of upper mantle heterogeneities on the lithospheric stress field and dynamic topography
Nonlinear viscoplasticity in ASPECT: benchmarking and applications to subduction
Tie points for Gondwana reconstructions from a structural interpretation of the Mozambique Basin, East Africa and the Riiser-Larsen Sea, Antarctica
Analytical solution for viscous incompressible Stokes flow in a spherical shell
The effect of sediment loading in Fennoscandia and the Barents Sea during the last glacial cycle on glacial isostatic adjustment observations
Global patterns in Earth's dynamic topography since the Jurassic: the role of subducted slabs
Breaking supercontinents; no need to choose between passive or active
The subduction dichotomy of strong plates and weak slabs
The deep Earth origin of the Iceland plume and its effects on regional surface uplift and subsidence
New data on geology of the Southern Urals: a concise summary of research after the period of EUROPROBE activity
Joshua Martin Guerrero, Frédéric Deschamps, Yang Li, Wen-Pin Hsieh, and Paul James Tackley
Solid Earth, 14, 119–135, https://doi.org/10.5194/se-14-119-2023, https://doi.org/10.5194/se-14-119-2023, 2023
Short summary
Short summary
The mantle thermal conductivity's dependencies on temperature, pressure, and composition are often suppressed in numerical models. We examine the effect of these dependencies on the long-term evolution of lower-mantle thermochemical structure. We propose that depth-dependent conductivities derived from mantle minerals, along with moderate temperature and compositional correction, emulate the Earth's mean lowermost-mantle conductivity values and produce a stable two-pile configuration.
Guoqiang Yan, Benjamin Busch, Robert Egert, Morteza Esmaeilpour, Kai Stricker, and Thomas Kohl
EGUsphere, https://doi.org/10.5194/egusphere-2022-1185, https://doi.org/10.5194/egusphere-2022-1185, 2022
Short summary
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The physical processes leading to the kilometer-scale thermal anomaly in faulted tight sandstones are numerically investigated. The fluid flow pathways, heat transfer types, and interactions among different convective and advective flow modes are systematically identified. The methodologies and results can be applied to interpret hydrothermal convection-related geological phenomena and to draw implications for future petroleum and geothermal exploration and exploitation in analogous settings.
Antonio Manjón-Cabeza Córdoba and Maxim D. Ballmer
Solid Earth, 13, 1585–1605, https://doi.org/10.5194/se-13-1585-2022, https://doi.org/10.5194/se-13-1585-2022, 2022
Short summary
Short summary
The origin of many volcanic archipelagos on the Earth remains uncertain. By using 3D modelling of mantle flow and melting, we investigate the interaction between the convective mantle near the continental–oceanic transition and rising hot plumes. We believe that this phenomenon is the origin behind some archipelagos, in particular the Canary Islands. Analysing our results, we reconcile observations that were previously enigmatic, such as the complex patterns of volcanism in the Canaries.
Adina E. Pusok, Dave R. Stegman, and Madeleine Kerr
Solid Earth, 13, 1455–1473, https://doi.org/10.5194/se-13-1455-2022, https://doi.org/10.5194/se-13-1455-2022, 2022
Short summary
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Sediments play an important role in global volatile and tectonic cycles, yet their effect on subduction dynamics is poorly resolved. In this study, we investigate how sediment properties influence subduction dynamics and obtain accretionary or erosive-style margins. Results show that even a thin layer of sediments can exert a profound influence on the emergent regional-scale subduction dynamics.
Laure Chevalier and Harro Schmeling
Solid Earth, 13, 1045–1063, https://doi.org/10.5194/se-13-1045-2022, https://doi.org/10.5194/se-13-1045-2022, 2022
Short summary
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Fluid flow through rock occurs in many geological settings on different scales, at different temperature conditions and with different flow velocities. Fluid is either in local thermal equilibrium with the host rock or not. We explore the parameters of porous flow and give scaling laws. These allow us to decide whether porous flows are in thermal equilibrium or not. Applied to magmatic systems, moving melts in channels or dikes moderately to strongly deviate from thermal equilibrium.
Iris van Zelst, Fabio Crameri, Adina E. Pusok, Anne Glerum, Juliane Dannberg, and Cedric Thieulot
Solid Earth, 13, 583–637, https://doi.org/10.5194/se-13-583-2022, https://doi.org/10.5194/se-13-583-2022, 2022
Short summary
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Geodynamic modelling provides a powerful tool to investigate processes in the Earth’s crust, mantle, and core that are not directly observable. In this review, we present a comprehensive yet concise overview of the modelling process with an emphasis on best practices. We also highlight synergies with related fields, such as seismology and geology. Hence, this review is the perfect starting point for anyone wishing to (re)gain a solid understanding of geodynamic modelling as a whole.
Igor Ognev, Jörg Ebbing, and Peter Haas
Solid Earth, 13, 431–448, https://doi.org/10.5194/se-13-431-2022, https://doi.org/10.5194/se-13-431-2022, 2022
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We present a new 3D crustal model of Volgo–Uralia, an eastern segment of the East European craton. We built this model by processing the satellite gravity data and using prior crustal thickness estimation from regional seismic studies to constrain the results. The modelling revealed a high-density body on the top of the mantle and otherwise reflected the main known features of the Volgo–Uralian crustal architecture. We plan to use the obtained model for further geothermal analysis of the region.
Fengping Pang, Jie Liao, Maxim Ballmer, and Lun Li
Solid Earth Discuss., https://doi.org/10.5194/se-2022-20, https://doi.org/10.5194/se-2022-20, 2022
Revised manuscript accepted for SE
Short summary
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Plume-ridge interaction is an intriguing geological process in plate tectonics. In this manuscript, we address the respective role of ridge suction vs plate drag in 2D thermomechanical models and compares the results with a compilation of observations on Earth. From a geophysical and geochemical analysis of Earth plumes and in combination with the model results, we propose that the absence of plumes interacting with ridges in the Pacific is largely caused by the presence of plate drag.
Cedric Thieulot and Wolfgang Bangerth
Solid Earth, 13, 229–249, https://doi.org/10.5194/se-13-229-2022, https://doi.org/10.5194/se-13-229-2022, 2022
Short summary
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One of the main numerical methods to solve the mass, momentum, and energy conservation equations in geodynamics is the finite-element method. Four main types of elements have been used in the past decades in hundreds of publications. For the first time we compare results obtained with these four elements on a series of geodynamical benchmarks and applications and draw conclusions as to which are the best ones and which are to be preferably avoided.
Jean Furstoss, Carole Petit, Clément Ganino, Marc Bernacki, and Daniel Pino-Muñoz
Solid Earth, 12, 2369–2385, https://doi.org/10.5194/se-12-2369-2021, https://doi.org/10.5194/se-12-2369-2021, 2021
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In the first part of this article, we present a new methodology that we have developed to model the deformation and the microstructural evolutions of olivine rocks, which make up the main part of the Earth upper mantle. In a second part, using this methodology we show that microstructural features such as small grain sizes and preferential grain orientations can localize strain at the same intensity and can act together to produce an even stronger strain localization.
Duan Li, Jinsong Du, Chao Chen, Qing Liang, and Shida Sun
Solid Earth Discuss., https://doi.org/10.5194/se-2021-117, https://doi.org/10.5194/se-2021-117, 2021
Revised manuscript not accepted
Short summary
Short summary
Oceanic magnetic anomalies are generally carried out using only few survey lines and thus there are many areas with data gaps. Traditional interpolation methods based on the morphological characteristics of data are not suitable for data with large gaps. The use of dual-layer equivalent-source techniques may improve the interpolation of magnetic anomaly fields in areas with sparse data which gives a good consideration to the extension of the magnetic lineation feature.
Anna Johanna Pia Gülcher, Maxim Dionys Ballmer, and Paul James Tackley
Solid Earth, 12, 2087–2107, https://doi.org/10.5194/se-12-2087-2021, https://doi.org/10.5194/se-12-2087-2021, 2021
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The lower mantle extends from 660–2890 km depth, making up > 50 % of the Earth’s volume. Its composition and structure, however, remain poorly understood. In this study, we investigate several hypotheses with computer simulations of mantle convection that include different materials: recycled, dense rocks and ancient, strong rocks. We propose a new integrated style of mantle convection including
piles,
blobs, and
streaksthat agrees with various observations of the deep Earth.
Lorenzo G. Candioti, Thibault Duretz, Evangelos Moulas, and Stefan M. Schmalholz
Solid Earth, 12, 1749–1775, https://doi.org/10.5194/se-12-1749-2021, https://doi.org/10.5194/se-12-1749-2021, 2021
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We quantify the relative importance of forces driving the dynamics of mountain building using two-dimensional computer simulations of long-term coupled lithosphere–upper-mantle deformation. Buoyancy forces can be as high as shear forces induced by far-field plate motion and should be considered when studying the formation of mountain ranges. The strength of rocks flooring the oceans and the density structure of the crust control deep rock cycling and the topographic elevation of orogens.
Olivier de Viron, Michel Van Camp, Alexia Grabkowiak, and Ana M. G. Ferreira
Solid Earth, 12, 1601–1634, https://doi.org/10.5194/se-12-1601-2021, https://doi.org/10.5194/se-12-1601-2021, 2021
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As the travel time of seismic waves depends on the Earth's interior properties, seismic tomography uses it to infer the distribution of velocity anomalies, similarly to what is done in medical tomography. We propose analysing the outputs of those models using varimax principal component analysis, which results in a compressed objective representation of the model, helping analysis and comparison.
Janik Dohmen and Harro Schmeling
Solid Earth, 12, 1549–1561, https://doi.org/10.5194/se-12-1549-2021, https://doi.org/10.5194/se-12-1549-2021, 2021
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In partially molten regions within the Earth, the melt is able to move separately from the surrounding rocks. This allows for the emergence of so-called solitary porosity waves, driven by compaction and decompaction due to the melt with higher buoyancy. Our numerical models can predict whether a partially molten region will ascend dominated by solitary waves or diapirism. Even in diapiris-dominated regions, solitary waves will build up and ascend as a swarm when the ascend time is long enough.
Xin Zhong, Marcin Dabrowski, and Bjørn Jamtveit
Solid Earth, 12, 817–833, https://doi.org/10.5194/se-12-817-2021, https://doi.org/10.5194/se-12-817-2021, 2021
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Elastic thermobarometry is an useful tool to recover paleo-pressure and temperature. Here, we provide an analytical model based on the Eshelby solution to calculate the residual stress and strain preserved in a mineral inclusion exhumed from depth. The method applies to ellipsoidal, anisotropic inclusions in infinite isotropic hosts. A finite-element method is also used for a facet effect. Volumetrically averaged stress is shown to be a good proxy for the overall heterogeneous stress stage.
David Hindle and Olivier Besson
Solid Earth Discuss., https://doi.org/10.5194/se-2021-36, https://doi.org/10.5194/se-2021-36, 2021
Revised manuscript accepted for SE
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By making a change to the way we solve the flexure equation, that describes how the earth's outer layer bends when it is subjected to loading by ice sheets or mountains , we develop new ways of using an old method from geodynamics. This lets us study the earth's outer layer by measuring a parameter called the elastic thickness, effectively how stiff and springy the outer layer is when it gets loaded, and and also how the earth's outer layer gets broken around its edges and in its interior.
Maximilian Lowe, Jörg Ebbing, Amr El-Sharkawy, and Thomas Meier
Solid Earth, 12, 691–711, https://doi.org/10.5194/se-12-691-2021, https://doi.org/10.5194/se-12-691-2021, 2021
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This study estimates the gravitational contribution from subcrustal density heterogeneities interpreted as subducting lithosphere beneath the Alps to the gravity field. We showed that those heterogeneities contribute up to 40 mGal of gravitational signal. Such density variations are often not accounted for in Alpine lithospheric models. We demonstrate that future studies should account for subcrustal density variations to provide a meaningful representation of the complex geodynamic Alpine area.
Antonio Manjón-Cabeza Córdoba and Maxim D. Ballmer
Solid Earth, 12, 613–632, https://doi.org/10.5194/se-12-613-2021, https://doi.org/10.5194/se-12-613-2021, 2021
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The study of intraplate volcanism can inform us about underlying mantle dynamic processes and thermal and/or compositional anomalies. Here, we investigated numerical models of mantle flow and melting of edge-driven convection (EDC), a potential origin for intraplate volcanism. Our most important conclusion is that EDC can only produce moderate amounts of mantle melting. By itself, EDC is insufficient to support the formation of voluminous island-building volcanism over several millions of years.
Davide Tadiello and Carla Braitenberg
Solid Earth, 12, 539–561, https://doi.org/10.5194/se-12-539-2021, https://doi.org/10.5194/se-12-539-2021, 2021
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We present an innovative approach to estimate a lithosphere density distribution model based on seismic tomography and gravity data. In the studied area, the model shows that magmatic events have increased density in the middle to lower crust, which explains the observed positive gravity anomaly. We interpret the densification through crustal intrusion and magmatic underplating. The proposed method has been tested in the Alps but can be applied to other geological contexts.
Daniela Paz Bolrão, Maxim D. Ballmer, Adrien Morison, Antoine B. Rozel, Patrick Sanan, Stéphane Labrosse, and Paul J. Tackley
Solid Earth, 12, 421–437, https://doi.org/10.5194/se-12-421-2021, https://doi.org/10.5194/se-12-421-2021, 2021
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We use numerical models to investigate the thermo-chemical evolution of a solid mantle during a magma ocean stage. When applied to the Earth, our study shows that the solid mantle and a magma ocean tend toward chemical equilibration before crystallisation of this magma ocean. Our findings suggest that a very strong chemical stratification of the solid mantle is unlikely to occur (as predicted by previous studies), which may explain why the Earth’s mantle is rather homogeneous in composition.
Ángela María Gómez-García, Eline Le Breton, Magdalena Scheck-Wenderoth, Gaspar Monsalve, and Denis Anikiev
Solid Earth, 12, 275–298, https://doi.org/10.5194/se-12-275-2021, https://doi.org/10.5194/se-12-275-2021, 2021
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The Earth’s crust beneath the Caribbean Sea formed at about 90 Ma due to large magmatic activity of a mantle plume, which brought molten material up from the deep Earth. By integrating diverse geophysical datasets, we image for the first time two fossil magmatic conduits beneath the Caribbean. The location of these conduits at 90 Ma does not correspond with the present-day Galápagos plume. Either this mantle plume migrated in time or these conduits were formed above another unknown plume.
Lorenzo G. Candioti, Stefan M. Schmalholz, and Thibault Duretz
Solid Earth, 11, 2327–2357, https://doi.org/10.5194/se-11-2327-2020, https://doi.org/10.5194/se-11-2327-2020, 2020
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With computer simulations, we study the interplay between thermo-mechanical processes in the lithosphere and the underlying upper mantle during a long-term (> 100 Myr) tectonic cycle of extension–cooling–convergence. The intensity of mantle convection is important for (i) subduction initiation, (ii) the development of single- or double-slab subduction zones, and (iii) the forces necessary to initiate subduction. Our models are applicable to the opening and closure of the western Alpine Tethys.
Patrick Sanan, Dave A. May, Matthias Bollhöfer, and Olaf Schenk
Solid Earth, 11, 2031–2045, https://doi.org/10.5194/se-11-2031-2020, https://doi.org/10.5194/se-11-2031-2020, 2020
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Mantle and lithospheric dynamics, elasticity, subsurface flow, and other fields involve solving indefinite linear systems. Tools include direct solvers (robust, easy to use, expensive) and advanced iterative solvers (complex, problem-sensitive). We show that a third option, ILDL preconditioners, requires less memory than direct solvers but is easy to use, as applied to 3D problems with parameter jumps. With included software, we hope to allow researchers to solve previously infeasible problems.
Philipp Eichheimer, Marcel Thielmann, Wakana Fujita, Gregor J. Golabek, Michihiko Nakamura, Satoshi Okumura, Takayuki Nakatani, and Maximilian O. Kottwitz
Solid Earth, 11, 1079–1095, https://doi.org/10.5194/se-11-1079-2020, https://doi.org/10.5194/se-11-1079-2020, 2020
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To describe permeability, a key parameter controlling fluid flows in the Earth’s subsurface, an accurate determination of permeability on the pore scale is necessary. For this reason, we sinter artificial glass bead samples with various
porosities, determining the microstructure and permeability using both
experimental and numerical approaches. Based on this we provide
parameterizations of permeability, which can be used as input parameters for
large-scale numerical models.
Mark D. Lindsay, Sandra Occhipinti, Crystal Laflamme, Alan Aitken, and Lara Ramos
Solid Earth, 11, 1053–1077, https://doi.org/10.5194/se-11-1053-2020, https://doi.org/10.5194/se-11-1053-2020, 2020
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Integrated interpretation of multiple datasets is a key skill required for better understanding the composition and configuration of the Earth's crust. Geophysical and 3D geological modelling are used here to aid the interpretation process in investigating anomalous and cryptic geophysical signatures which suggest a more complex structure and history of a Palaeoproterozoic basin in Western Australia.
Tomáš Fischer, Josef Vlček, and Martin Lanzendörfer
Solid Earth, 11, 983–998, https://doi.org/10.5194/se-11-983-2020, https://doi.org/10.5194/se-11-983-2020, 2020
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Data on CO2 degassing help understanding the relations of the gas flow on geodynamic processes. Long-term gas flow measurements in rough field conditions present a challenge due to technical problems. We describe methods used for CO2 flow monitoring in West-Bohemia/Vogtland, which is typical for high CO2 flow, and present a new robust method based on pressure measurements in a water column. The results of 10 years of CO2 flow measurements and their relation to seismic activity are discussed.
Jana Schierjott, Antoine Rozel, and Paul Tackley
Solid Earth, 11, 959–982, https://doi.org/10.5194/se-11-959-2020, https://doi.org/10.5194/se-11-959-2020, 2020
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We investigate the size of mineral grains of Earth's rocks in computer models of the whole Earth. This is relevant because grain size affects the stiffness (large grains are stiffer) and deformation of the Earth's mantle. We see that mineral grains grow inside stable non-deforming regions of the Earth. However, these regions are less stiff than expected. On the other hand, we find that grain size diminishes during deformation events such as when surface material comes down into the Earth.
Irene Pérez-Cáceres, David Jesús Martínez Poyatos, Olivier Vidal, Olivier Beyssac, Fernando Nieto, José Fernando Simancas, Antonio Azor, and Franck Bourdelle
Solid Earth, 11, 469–488, https://doi.org/10.5194/se-11-469-2020, https://doi.org/10.5194/se-11-469-2020, 2020
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The metamorphism of the Pulo do Lobo unit (SW Iberian Massif) is described in this paper. To this end, three different and complementary methodologies have been applied. The new results reported here contribute to the knowledge of the metamorphic conditions of the Pulo do Lobo unit in relation to its deformation. Furthermore, the results are compared in order to assess the reliability of the different methods applied.
Ömer F. Bodur and Patrice F. Rey
Solid Earth, 10, 2167–2178, https://doi.org/10.5194/se-10-2167-2019, https://doi.org/10.5194/se-10-2167-2019, 2019
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Convection in the deep Earth dynamically changes the elevation of plates. Amplitudes of those vertical motions predicted from numerical models are significantly higher than observations. We find that at small wavelengths (< 1000 km) this misfit can be due to the oversimplification in viscosity of rocks. By a suite of numerical experiments, we show that considering the non–Newtonian rheology of the mantle results in predictions in amplitude of dynamic topography consistent with observations.
Janik Dohmen, Harro Schmeling, and Jan Philipp Kruse
Solid Earth, 10, 2103–2113, https://doi.org/10.5194/se-10-2103-2019, https://doi.org/10.5194/se-10-2103-2019, 2019
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In source regions of magmatic systems the temperature is above solidus and melt ascent is assumed to occur predominantly by two-phase flow. This two-phase flow allows for the emergence of solitary porosity waves. By now most solutions of these waves used strongly simplified viscosity laws, while in our laws the viscosity decreases rapidly for small melt fractions. The results show that for higher background porosities the phase velocities and the width of the wave are significantly decreased.
Cameron Spooner, Magdalena Scheck-Wenderoth, Hans-Jürgen Götze, Jörg Ebbing, György Hetényi, and the AlpArray Working Group
Solid Earth, 10, 2073–2088, https://doi.org/10.5194/se-10-2073-2019, https://doi.org/10.5194/se-10-2073-2019, 2019
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By utilising both the observed gravity field of the Alps and their forelands and indications from deep seismic surveys, we were able to produce a 3-D structural model of the region that indicates the distribution of densities within the lithosphere. We found that the present-day Adriatic crust is both thinner and denser than the European crust and that the properties of Alpine crust are strongly linked to their provenance.
Philipp Eichheimer, Marcel Thielmann, Anton Popov, Gregor J. Golabek, Wakana Fujita, Maximilian O. Kottwitz, and Boris J. P. Kaus
Solid Earth, 10, 1717–1731, https://doi.org/10.5194/se-10-1717-2019, https://doi.org/10.5194/se-10-1717-2019, 2019
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Prediction of rock permeability is of crucial importance for several research areas in geoscience. In this study, we enhance the finite difference code LaMEM to compute fluid flow on the pore scale using Newtonian and non-Newtonian rheologies. The accuracy of the code is demonstrated using several analytical solutions as well as experimental data. Our results show good agreement with analytical solutions and recent numerical studies.
Ershad Gholamrezaie, Magdalena Scheck-Wenderoth, Judith Bott, Oliver Heidbach, and Manfred R. Strecker
Solid Earth, 10, 785–807, https://doi.org/10.5194/se-10-785-2019, https://doi.org/10.5194/se-10-785-2019, 2019
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Based on geophysical data integration and 3-D gravity modeling, we show that significant density heterogeneities are expressed as two large high-density bodies in the crust below the Sea of Marmara. The location of these bodies correlates spatially with the bends of the main Marmara fault, indicating that rheological contrasts in the crust may influence the fault kinematics. Our findings may have implications for seismic hazard and risk assessments in the Marmara region.
Sascha Brune, Simon E. Williams, and R. Dietmar Müller
Solid Earth, 9, 1187–1206, https://doi.org/10.5194/se-9-1187-2018, https://doi.org/10.5194/se-9-1187-2018, 2018
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Fragmentation of continents often involves obliquely rifting segments that feature a complex three-dimensional structural evolution. Here we show that more than ~ 70 % of Earth’s rifted margins exceeded an obliquity of 20° demonstrating that oblique rifting should be considered the rule, not the exception. This highlights the importance of three-dimensional approaches in modelling, surveying, and interpretation of those rift segments where oblique rifting is the dominant mode of deformation.
Cedric Thieulot
Solid Earth, 9, 1169–1177, https://doi.org/10.5194/se-9-1169-2018, https://doi.org/10.5194/se-9-1169-2018, 2018
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I present the GHOST (Geoscientific Hollow Sphere Tessellation) software which allows for the fast generation of computational meshes in hollow sphere geometries counting up to a hundred million cells. Each mesh is composed of concentric spherical shells made of quadrilaterals or triangles. I focus here on three commonly used meshes used in the geodynamics/geophysics community and further benchmark the gravity and gravitational potential procedures in the simple case of a constant density.
Foteini Vervelidou, Erwan Thébault, and Monika Korte
Solid Earth, 9, 897–910, https://doi.org/10.5194/se-9-897-2018, https://doi.org/10.5194/se-9-897-2018, 2018
Tara L. Stephens, Richard J. Walker, David Healy, Alodie Bubeck, and Richard W. England
Solid Earth, 9, 847–858, https://doi.org/10.5194/se-9-847-2018, https://doi.org/10.5194/se-9-847-2018, 2018
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We present mechanical models that use the attitude and opening angles of igneous sills to constrain stress axes, the stress ratio, and relative magma pressure during dilation. The models can be applied to any set of dilated structures, including dikes, sills, or veins. Comparison with paleostress analysis for coeval faults and deformation bands indicates that sills can be used to characterise the paleostress state in areas where other brittle deformation structures (e.g. faults) are not present.
Mikhail K. Kaban, Sami El Khrepy, and Nassir Al-Arifi
Solid Earth, 9, 833–846, https://doi.org/10.5194/se-9-833-2018, https://doi.org/10.5194/se-9-833-2018, 2018
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We present an integrative model of the crust and upper mantle of Egypt based on an analysis of gravity, seismic, and geological data. These results are essential for deciphering the link between the dynamic processes in the Earth system and near-surface processes (particularly earthquakes) that influence human habitat. We identified the distinct fragmentation of the lithosphere of Egypt in several blocks. This division is closely related to the seismicity patterns in this region.
Alexis Plunder, Cédric Thieulot, and Douwe J. J. van Hinsbergen
Solid Earth, 9, 759–776, https://doi.org/10.5194/se-9-759-2018, https://doi.org/10.5194/se-9-759-2018, 2018
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The thermal state of the Earth's crust determines how it reacts to tectonic forces and to fluid flow responsible for ore formation. We hypothesize that the angle between plate motion and convergent boundaries determines the thermal regime of subduction zones (where a plate goes under another one). Computer models and a geological reconstruction of Turkey were used to validate this hypothesis.
This research was done to validate a hypothesis made on the basis of nonquantitative field data.
Anthony Osei Tutu, Bernhard Steinberger, Stephan V. Sobolev, Irina Rogozhina, and Anton A. Popov
Solid Earth, 9, 649–668, https://doi.org/10.5194/se-9-649-2018, https://doi.org/10.5194/se-9-649-2018, 2018
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The Earth's surface is characterized by numerous geological processes, formed throughout the Earth's history to present day. The interior (mantle), on which plates rest, undergoes convection motion, generating stresses in the lithosphere plate and also causing the plate motion. This study shows that shallow density heterogeneities in the upper 300 km have a limited influence on the modeled horizontal stress field as opposed to the resulting topography, giving the importance depth sampling.
Anne Glerum, Cedric Thieulot, Menno Fraters, Constantijn Blom, and Wim Spakman
Solid Earth, 9, 267–294, https://doi.org/10.5194/se-9-267-2018, https://doi.org/10.5194/se-9-267-2018, 2018
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A nonlinear viscoplastic rheology is implemented and benchmarked in the ASPECT software, allowing for the modeling of lithospheric deformation. We showcase the new functionality with a four-dimensional model of thermomechanically coupled subduction.
Jennifer Klimke, Dieter Franke, Estevão Stefane Mahanjane, and German Leitchenkov
Solid Earth, 9, 25–37, https://doi.org/10.5194/se-9-25-2018, https://doi.org/10.5194/se-9-25-2018, 2018
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In this paper, we present a combined structural interpretation of multichannel reflection seismic profiles from offshore of northern Mozambique (East Africa) and the conjugate Riiser-Larsen Sea (Antarctica). At certain positions at the foot of the continental slope at both basins, the basement is intensely deformed and fractured. We propose this unique deformation zone as a tie point for Gondwana reconstructions.
Cedric Thieulot
Solid Earth, 8, 1181–1191, https://doi.org/10.5194/se-8-1181-2017, https://doi.org/10.5194/se-8-1181-2017, 2017
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I present a new family of analytical flow solutions to the incompressible Stokes equation in a spherical shell. The velocity is tangential to both inner and outer boundaries, the viscosity is radial, and the solution has been designed so that the expressions for velocity, pressure, and body force are simple to implement in (geodynamics) codes. This forms the basis of a numerical benchmark for convection codes, and I have implemented it in two finite-element codes.
Wouter van der Wal and Thijs IJpelaar
Solid Earth, 8, 955–968, https://doi.org/10.5194/se-8-955-2017, https://doi.org/10.5194/se-8-955-2017, 2017
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As ice sheets grow and shrink, they move rocks around. In Scandinavia the movement took place mostly from inland to offshore areas, resulting in ongoing uplift in Scandinavia and subsidence in offshore areas. This study calculated the changes in height and gravity and found that they are significant. Thus, effects of past sediment loading have to be taken into account when interpreting measurements of height and gravity change in areas close to former ice sheets with large sediment transport.
Michael Rubey, Sascha Brune, Christian Heine, D. Rhodri Davies, Simon E. Williams, and R. Dietmar Müller
Solid Earth, 8, 899–919, https://doi.org/10.5194/se-8-899-2017, https://doi.org/10.5194/se-8-899-2017, 2017
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Earth's surface is constantly warped up and down by the convecting mantle. Here we derive geodynamic rules for this so-called
dynamic topographyby employing high-resolution numerical models of global mantle convection. We define four types of dynamic topography history that are primarily controlled by the ever-changing pattern of Earth's subduction zones. Our models provide a predictive quantitative framework linking mantle convection with plate tectonics and sedimentary basin evolution.
Martin Wolstencroft and J. Huw Davies
Solid Earth, 8, 817–825, https://doi.org/10.5194/se-8-817-2017, https://doi.org/10.5194/se-8-817-2017, 2017
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A key aspect of plate tectonics is the periodic assembly and subsequent break-up of supercontinents. There is strong evidence that this has happened repeatedly over geological history, but exactly how a supercontinent breaks up is still debated. In this paper, we use computer modelling of Earth's interior to show that the force needed to break a supercontinent should always arise from a combination of global-scale passive
pulling apartand active
pushing apartforces driven by the mantle.
Robert I. Petersen, Dave R. Stegman, and Paul J. Tackley
Solid Earth, 8, 339–350, https://doi.org/10.5194/se-8-339-2017, https://doi.org/10.5194/se-8-339-2017, 2017
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In this study we propose a dichotomy in the strength profile of tectonic plates. This apparent dichotomy suggests that plates at the Earth's surface are significantly stronger, by orders of magnitude, than the subducted slabs in the Earth's interior. Strong plates promote single-sided, Earth-like subduction. Once subducted, strong slabs transmit dynamic stresses and disrupt subduction. Slabs which are weakened do not disrupt subduction and furthermore exhibit a variety of observed morphologies.
Nicholas Barnett-Moore, Rakib Hassan, Nicolas Flament, and Dietmar Müller
Solid Earth, 8, 235–254, https://doi.org/10.5194/se-8-235-2017, https://doi.org/10.5194/se-8-235-2017, 2017
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We use 3D mantle flow models to investigate the evolution of the Iceland plume in the North Atlantic. Results show that over the last ~ 100 Myr a remarkably stable pattern of flow in the lowermost mantle beneath the region resulted in the formation of a plume nucleation site. At the surface, a model plume compared to published observables indicates that its large plume head, ~ 2500 km in diameter, arriving beneath eastern Greenland in the Palaeocene, can account for the volcanic record and uplift.
Victor N. Puchkov
Solid Earth, 7, 1269–1280, https://doi.org/10.5194/se-7-1269-2016, https://doi.org/10.5194/se-7-1269-2016, 2016
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The period between 1991 and 2005 was a time when many western geologists came to the Urals to get a closer look at this famous and extraordinarily rich region. The main reason was an openness policy of the USSR government, when foreigners were admitted to this area that was formerly almost closed. The co-operation of the western geologists with local specialists was very fruitful. The author aimed to describe the most interesting findings in Uralian geology after the learned guests left.
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