Articles | Volume 3, issue 2
https://doi.org/10.5194/se-3-415-2012
© Author(s) 2012. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Special issue:
https://doi.org/10.5194/se-3-415-2012
© Author(s) 2012. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Subduction to the lower mantle – a comparison between geodynamic and tomographic models
B. Steinberger
GeoForschungsZentrum Potsdam, Telegrafenberg, 14473 Potsdam, Germany
Physics of Geological Processes and Geosciences, University of Oslo, Blindern, 0316 Oslo, Norway
T. H. Torsvik
Physics of Geological Processes and Geosciences, University of Oslo, Blindern, 0316 Oslo, Norway
Center for Geodynamics, Geological Survey of Norway, Leiv Eirikssons vei 39, 7491 Trondheim, Norway
School of Geosciences, University of the Witwatersrand, Wits 2050, South Africa
T. W. Becker
Department of Earth Sciences, University of Southern California, 3651 Trousdale Pkwy., Los Angeles, CA 90089-0740, USA
Related subject area
Geodynamics
How a volcanic arc influences back-arc extension: insight from 2D numerical models
Quantifying mantle mixing through configurational entropy
Various lithospheric deformation patterns derived from rheological contrasts between continental terranes: insights from 2-D numerical simulations
Magmatic underplating associated with Proterozoic basin formation: insights from gravity study over the southern margin of the Bundelkhand Craton, India
On the impact of true polar wander on heat flux patterns at the core–mantle boundary
The influence of viscous slab rheology on numerical models of subduction
Statistical appraisal of geothermal heat flow observations in the Arctic
Fast uplift in the southern Patagonian Andes due to long- and short-term deglaciation and the asthenospheric window underneath
ECOMAN: an open-source package for geodynamic and seismological modeling of mechanical anisotropy
Modeling liquid transport in the Earth's mantle as two-phase flow: effect of an enforced positive porosity on liquid flow and mass conservation
Thrusts control the thermal maturity of accreted sediments
The crustal structure of the Longmenshan fault zone and its implications for seismogenesis: new insight from aeromagnetic and gravity data
Earth's core variability from magnetic and gravity field observations
The role of continental lithospheric thermal structure in the evolution of orogenic systems: application to the Himalayan–Tibetan collision zone
Glacial-isostatic-adjustment strain rate–stress paradox in the Western Alps and impact on active faults and seismicity
The effect of temperature-dependent material properties on simple thermal models of subduction zones
Plume–ridge interactions: ridgeward versus plate-drag plume flow
Transport mechanisms of hydrothermal convection in faulted tight sandstones
A corrected finite-difference scheme for the flexure equation with abrupt changes in coefficient
Influence of heterogeneous thermal conductivity on the long-term evolution of the lower-mantle thermochemical structure: implications for primordial reservoirs
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
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
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
Duo Zhang and J. Huw Davies
Solid Earth, 15, 1113–1132, https://doi.org/10.5194/se-15-1113-2024, https://doi.org/10.5194/se-15-1113-2024, 2024
Short summary
Short summary
We numerically model the influence of an arc on back-arc extension. The arc is simulated by placing a hot region on the overriding plate. We investigate how plate ages and properties of the hot region affect back-arc extension and present regime diagrams illustrating the nature of back-arc extension for these models. We find that back-arc extension occurs not only in the hot region but also, surprisingly, away from it, and a hot region facilitates extension on the overriding plate.
Erik van der Wiel, Cedric Thieulot, and Douwe J. J. van Hinsbergen
Solid Earth, 15, 861–875, https://doi.org/10.5194/se-15-861-2024, https://doi.org/10.5194/se-15-861-2024, 2024
Short summary
Short summary
Geodynamic models of mantle convection provide a powerful tool to study the structure and composition of the Earth's mantle. Comparing such models with other datasets is difficult. We explore the use of
configurational entropy, which allows us to quantify mixing in models. The entropy may be used to analyse the mixed state of the mantle as a whole and may also be useful to validate numerical models against anomalies in the mantle that are obtained from seismology and geochemistry.
Renxian Xie, Lin Chen, Jason P. Morgan, and Yongshun John Chen
Solid Earth, 15, 789–806, https://doi.org/10.5194/se-15-789-2024, https://doi.org/10.5194/se-15-789-2024, 2024
Short summary
Short summary
Continental terranes have various rheological strengths due to the differences in their ages, compositions, and structures. We applied four assumed rheological models to three terranes in a collisional model and obtained four styles of lithosphere deformation patterns of collision, subduction, thickening/delamination, and replacement. These simulation patterns are seen in observed lithosphere deformation patterns and structures in East Asia.
Ananya Parthapradip Mukherjee and Animesh Mandal
Solid Earth, 15, 711–729, https://doi.org/10.5194/se-15-711-2024, https://doi.org/10.5194/se-15-711-2024, 2024
Short summary
Short summary
Global gravity data are used to develop 2D models and a Moho depth map from 3D inversion, depicting the crustal structure below the region covered by Proterozoic sedimentary basins, south of the Bundelkhand Craton in central India. The observed thick mafic underplated layer above the Moho indicates Proterozoic plume activity. Thus, the study offers insights into the crustal configuration of this region, illustrating the geodynamic processes that led to the formation of the basins.
Thomas Frasson, Stéphane Labrosse, Henri-Claude Nataf, Nicolas Coltice, and Nicolas Flament
Solid Earth, 15, 617–637, https://doi.org/10.5194/se-15-617-2024, https://doi.org/10.5194/se-15-617-2024, 2024
Short summary
Short summary
Heat flux heterogeneities at the bottom of Earth's mantle play an important role in the dynamic of the underlying core. Here, we study how these heterogeneities are affected by the global rotation of the Earth, called true polar wander (TPW), which has to be considered to relate mantle dynamics with core dynamics. We find that TPW can greatly modify the large scales of heat flux heterogeneities, notably at short timescales. We provide representative maps of these heterogeneities.
Natalie Hummel, Susanne Buiter, and Zoltán Erdős
Solid Earth, 15, 567–587, https://doi.org/10.5194/se-15-567-2024, https://doi.org/10.5194/se-15-567-2024, 2024
Short summary
Short summary
Simulations of subducting tectonic plates often use material properties extrapolated from the behavior of small rock samples in a laboratory to conditions found in the Earth. We explore several typical approaches to simulating these extrapolated material properties and show that they produce very rigid subducting plates with unrealistic dynamics. Our findings imply that subducting plates deform by additional mechanisms that are less commonly implemented in simulations.
Judith Freienstein, Wolfgang Szwillus, Agnes Wansing, and Jörg Ebbing
Solid Earth, 15, 513–533, https://doi.org/10.5194/se-15-513-2024, https://doi.org/10.5194/se-15-513-2024, 2024
Short summary
Short summary
Geothermal heat flow influences ice sheet dynamics, making its investigation important for ice-covered regions. Here we evaluate the sparse measurements for their agreement with regional solid Earth models, as well as with a statistical approach. This shows that some points should be excluded from regional studies. In particular, the NGRIP point, which strongly influences heat flow maps and the distribution of high basal melts, should be statistically considered an outlier.
Veleda A. P. Muller, Pietro Sternai, and Christian Sue
Solid Earth, 15, 387–404, https://doi.org/10.5194/se-15-387-2024, https://doi.org/10.5194/se-15-387-2024, 2024
Short summary
Short summary
Uplift rates up to 40 mm yr−1 are measured by GNSS in the southern Patagonian Icefield, a remainder of the Patagonian Ice Sheet that covered the Andes in the Last Glacial Maximum (LGM) at 26 ka. Using numerical modelling, we estimate an increase of 150 to 200 °C of the asthenospheric temperature due to the slab window under southern Patagonia, and we show that post-glacial rebound, after the long-term LGM and the short-term Little Ice Age (400 a), contributed to the modern uplift rate budget.
Manuele Faccenda, Brandon Paul VanderBeek, Albert de Montserrat, Jianfeng Yang, and Neil Ribe
EGUsphere, https://doi.org/10.5194/egusphere-2024-299, https://doi.org/10.5194/egusphere-2024-299, 2024
Short summary
Short summary
The Earth's internal dynamics and structure can be well understood by combining seismological and geodynamic modeling with mineral physics, an approach that has been poorly adopted in the past. To this end we have developed ECOMAN, an open-source software package that is intended to overcome the computationally intensive nature of this multidisciplinary methodology and the lack of a dedicated and comprehensive computational framework.
Changyeol Lee, Nestor G. Cerpa, Dongwoo Han, and Ikuko Wada
Solid Earth, 15, 23–38, https://doi.org/10.5194/se-15-23-2024, https://doi.org/10.5194/se-15-23-2024, 2024
Short summary
Short summary
Fluids and melts in the mantle are key to the Earth’s evolution. The main driving force for their transport is the compaction of the porous mantle. Numerically, the compaction equations can yield unphysical negative liquid fractions (porosity), and it is necessary to enforce positive porosity. However, the effect of such a treatment on liquid flow and mass conservation has not been quantified. We found that although mass conservation is affected, the liquid pathways are well resolved.
Utsav Mannu, David Fernández-Blanco, Ayumu Miyakawa, Taras Gerya, and Masataka Kinoshita
Solid Earth, 15, 1–21, https://doi.org/10.5194/se-15-1-2024, https://doi.org/10.5194/se-15-1-2024, 2024
Short summary
Short summary
Accretion during subduction, in which one tectonic plate moves under another, forms a wedge where sediments can be transformed into hydrocarbons. We utilised realistic computer models to investigate this and, in particular, how accretion affects mobility in the wedge and found that the evolution of the wedge and the thrusts it develops fundamentally control the thermal maturity of sediments. This can help us better understand the history of subduction and the formation of hydrocarbons in wedges.
Hai Yang, Shengqing Xiong, Qiankun Liu, Fang Li, Zhiye Jia, Xue Yang, Haofei Yan, and Zhaoliang Li
Solid Earth, 14, 1289–1308, https://doi.org/10.5194/se-14-1289-2023, https://doi.org/10.5194/se-14-1289-2023, 2023
Short summary
Short summary
The Wenchuan (Ms 8.0) and Lushan (Ms 7.0) earthquakes show different geodynamic features and form a 40–60 km area void of aftershocks for both earthquakes. The inverse models suggest that the downward-subducted basement of the Sichuan Basin is irregular in shape and heterogeneous in magnetism and density. The different focal mechanisms of the two earthquakes and the genesis of the seismic gap may be closely related to the differential thrusting mechanism caused by basement heterogeneity.
Anita Thea Saraswati, Olivier de Viron, and Mioara Mandea
Solid Earth, 14, 1267–1287, https://doi.org/10.5194/se-14-1267-2023, https://doi.org/10.5194/se-14-1267-2023, 2023
Short summary
Short summary
To understand core dynamics, insight from several possible observables is needed. By applying several separation methods, we show spatiotemporal variabilities in the magnetic and gravity fields related to the core dynamics. A 7-year oscillation is found in all conducted analyses. The results in the magnetic field reflect the core processes and the variabilities in the gravity field exhibit new findings that might be an interesting input to build an enhanced model of the Earth’s core.
Mengxue Liu, Dinghui Yang, and Rui Qi
Solid Earth, 14, 1155–1168, https://doi.org/10.5194/se-14-1155-2023, https://doi.org/10.5194/se-14-1155-2023, 2023
Short summary
Short summary
The continuous subduction mainly occurs with a relatively cold overriding lithosphere (Tmoho ≤ 450 °C), while slab break-off dominates when the model has a relatively hot procontinental Moho temparature (Tmoho ≥ 500 °C). Hr is more prone to facilitating the deformation of the lithospheric upper part than altering the collision mode. The lithospheric thermal structure may have played a significant role in the development of Himalayan–Tibetan orogenic lateral heterogeneity.
Juliette Grosset, Stéphane Mazzotti, and Philippe Vernant
Solid Earth, 14, 1067–1081, https://doi.org/10.5194/se-14-1067-2023, https://doi.org/10.5194/se-14-1067-2023, 2023
Short summary
Short summary
In glaciated regions, induced lithosphere deformation is proposed as a key process contributing to fault activity and seismicity. We study the impact of this effect on fault activity in the Western Alps. We show that the response to the last glaciation explains a major part of the geodetic strain rates but does not drive or promote the observed seismicity. Thus, seismic hazard studies in the Western Alps require detailed modeling of the glacial isostatic adjustment (GIA) transient impact.
Iris van Zelst, Cedric Thieulot, and Timothy J. Craig
Solid Earth, 14, 683–707, https://doi.org/10.5194/se-14-683-2023, https://doi.org/10.5194/se-14-683-2023, 2023
Short summary
Short summary
A common simplification in subduction zone models is the use of constant thermal parameters, while experiments have shown that they vary with temperature. We test various formulations of temperature-dependent thermal parameters and show that they change the thermal structure of the subducting slab. We recommend that modelling studies of the thermal structure of subduction zones take the temperature dependence of thermal parameters into account, especially when providing insights into seismicity.
Fengping Pang, Jie Liao, Maxim D. Ballmer, and Lun Li
Solid Earth, 14, 353–368, https://doi.org/10.5194/se-14-353-2023, https://doi.org/10.5194/se-14-353-2023, 2023
Short summary
Short summary
Plume–ridge interaction is an intriguing geological process in plate tectonics. In this paper, we address the respective role of ridgeward vs. plate-drag plume flow in 2D thermomechanical models and compare 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.
Guoqiang Yan, Benjamin Busch, Robert Egert, Morteza Esmaeilpour, Kai Stricker, and Thomas Kohl
Solid Earth, 14, 293–310, https://doi.org/10.5194/se-14-293-2023, https://doi.org/10.5194/se-14-293-2023, 2023
Short summary
Short summary
The physical processes leading to the kilometre-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.
David Hindle and Olivier Besson
Solid Earth, 14, 197–212, https://doi.org/10.5194/se-14-197-2023, https://doi.org/10.5194/se-14-197-2023, 2023
Short summary
Short summary
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 also how the Earth's outer layer gets broken around its edges and in its interior.
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.
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
Short summary
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
Short summary
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
Short summary
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
Short summary
Short summary
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.
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
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
Cited articles
Akaogi, M. and Ito, E.: Calorimetric study on majorite–perovskite transition in the system Mg4Si4O12–Mg3Al2Si3O12: transition boundaries with positive pressure-temperature slopes, Phys. Earth Planet. Int., 114, 129–140, 1999.
Becker, T. W. and Boschi, L.: A comparison of tomographic and geodynamic mantle models, Geochem. Geophys. Geosys., 3, 1003, https://doi.org/10.1029/2001GC000168, 2002.
Becker, T. W. and O'Connell, R. J.: Predicting plate velocities with geodynamic models, Geochem. Geophys. Geosys., 2, 12, https://doi.org/10.1029/2001GC000171, 2001.
Bevis, M., Taylor, F. W., Schutz, B. E., Recy, J., Isacks, B. L., Hely, S., Singh, R., Kendrick, E., Stowell, J., Taylor, B. and Calmant, S.: Geodetic observations of very rapid convergence and back-arc extension at the Tonga arc, Nature, 374, 249–251, https://doi.org/10.1038/374249a0, 1995.
Biggin, A. J., Steinberger, B., Aubert, J., Suttie, N., Holme, R., Torsvik, T. H., van der Meer, D. G. and van Hinsbergen, D. J. J.: Possible links between long-term geomagnetic variations and whole-mantle convection processes, Nat. Geosci., 5, 526–533, https://doi.org/10.1038/ngeo1521, 2012.
Bijwaard, H., Spakman, W. and E. R. Engdahl, E. R.: Closing the gap between regional and global travel time tomography, J. Geophys. Res., 103, 30055–30078, https://doi.org/10.1029/98JB02467, 1998.
Bird, P.: Formation of the Rocky Mountains, western United States: A continuum computer model, Science, 239, 1501–1507, 1988.
Boschi, L., Becker, T. W., and Steinberger, B.: Mantle plumes: dynamic models and seismic images, Geochem. Geophys. Geosyst., 8, Q10006, https://doi.org/10.1029/2007GC001733, 2007.
Boschi, L., Becker, T. W., and Steinberger, B.: On the statistical significance of correlations between synthetic mantle plumes and tomographic models, Phys. Earth Planet. Int., 167, 230–238, https://doi.org/10.1016/j.pepi.2008.03.009, 2008.
Buiter, S. J. H., Steinberger, B., Medvedev, S., and Tetreault, J. L.: Could the mantle have caused subsidence of the Congo Basin? Tectonophysics, 514–517, 62–80, 2012.
Bull, A. L., McNamara, A. K., and Ritsema, J.: Synthetic tomography of Plume Clusters and Thermochemical Piles, Earth Planet. Sci. Lett., 278, 152–162, 2009.
Bunge, H.-P. and Grand, S. P.: Mesozoic plate-motion history below the northeast Pacific Ocean from seismic images of the subducted Farallon slab, Nature, 405, 337–340, 2000.
Čížková, H., van den Berg, A.P., Spakman, W. and Matyska, C.: The viscosity of Earth's lower mantle inferred from sinking speed of subducted lithosphere, Phys. Earth Planet. Int., 200–201, 56–62, 2012.
Conrad, C. P. and Lithgow-Bertelloni, C.: How mantle slabs drive plate tectonics, Science, 298, 207–209, 2002.
Fukao, Y., Widiyantoro, S., and Obayashi, M.: Stagnant slabs in the upper and lower mantle transition region, Rev. Geophys., 39, 291–323, 2001.
Garnero, E. J. and McNamara, A. K.: Structure and dynamics of the Earth's lower mantle, Science, 320, 626–628, 2008.
Ghosh, A., Becker, T. W., and Zhong, S.: Effects of lateral viscosity variations on the geoid, Geophys. Res. Lett, 37, L01301, https://doi.org/10.1029/2009GL040426, 2010.
Grand, S. P., Van der Hilst, R. D., and Widiyantoro, S.: Global seismic tomography: snapshot of convection in the Earth, GSA Today, 7, 1–7, 1997.
Gurnis, M. and Mueller, R. D.: The Origin of the Australian Antarctic Discordance from an ancient slab and mantle wedge, in Hillis, R. R., and Mueller, R. D., The Evolution and Dynamics of the Australian Plate, Geological Societies of Australia Special Publication 22 and Geological Society of America Special Paper, 372, 417–429, 2003.
Hafkenscheid, E., Wortel, M. J. R., and Spakman, W.: Subduction history of the Tethyan region derived from seismic tomography and tectonic reconstructions, J. Geophys. Res., 111, B08401, https://doi.org/10.1029/2005JB003791, 2006.
Hager, B. H. and O'Connell, R. J.: Kinematic models of large-scale flow in the Earth's mantle, J. Geophys. Res., 84, 1031–1048, 1979.
Hager, B. H. and O'Connell, R. J.: A simple global model of plate dynamics and mantle convection, J. Geophys. Res., 86, 4843–4867, 1981.
Hwang, Y. K., Ritsema, J., van Keken, P. E., Goes, S., and Styles, E.: Wavefront healing renders deep plumes seismically invisible, Geophys. J. Int., 187, 273–277, 2011.
Isacks, B.: Uplift of the central Andean plateau and bending of the Bolivian orocline, J. Geophys. Res., 93, 3211–3231, 1988.
Li, C., van der Hilst, R. D., Engdahl, E. R., and Burdick, S.: A new global model for P wave speed variations in Earth's mantle, Geochem. Geophys. Geosys., 9, Q05018, https://doi.org/10.1029/2007GC001806, 2008.
Lithgow-Bertelloni, C. and Richards, M. A.: The dynamics of Cenozoic and Mesozoic plate motions, Rev. Geophys., 36, 27–78, 1998.
Liu, L., Spasojević, S. and Gurnis, M.: Reconstructing Farallon Plate Subduction Beneath North America Back to the Late Cretaceous, Science, 322, 934–938, 2008.
Masters, G., Laske, G., Bolton, H., and Dziewo\'{n}ski, A. M.: The relative behavior of shear velocity, bulk sound speed, and compressional velocity in the mantle: implications for chemical and thermal structure, in: Mineral physics and tomography from the atomic to the global scale, eduted by: Karato, S.-I., Forte, A. M., Liebermann, R. C., Masters, G., and Stixrude, L.: Earth's deep interior, Geophys. Monograph Series, 117, 63–87, Am. Geophys. Un., Washington DC, 2000.
McNamara, A. K. and Zhong, S.: Thermochemical structures beneath Africa and the Pacific ocean, Nature, 437, 1136–1139, 2005.
Mégnin, C., Bunge, H.-P., Romanowicz, B., and Richards, M. A.: Imaging 3-D spherical convection models: what can seismic tomography tell us about mantle dynamics? Geophys. Res. Lett., 24, 1299–1302, 1997.
Mitrovica, J. X.: Haskell (1935) revisited, J. Geophys. Res., 101, 555–569, 1996.
Press, W. H., Flannery, B. P., Teukolsky, S. A., and Vetterling, W. T.: Numerical Recipes: The Art of Scientific Computing, Cambridge Univ. Press, Cambridge, U. K., 1986.
Qin, Y., Capdeville, Y., Montagner, J.-P., Boschi, L., and Becker, T. W.: Reliability of mantle tomography models assessed by spectral-element simulation, Geophys. J. Int., 177, 125–144, 2009.
Ray, T. R. and Anderson, D. L.: Spherical disharmonics in the Earth sciences and the spatial solution: Ridges, hotspots, slabs, geochemistry and tomography correlations, J. Geophys. Res., 99, 9605–9614, 1994.
Ricard, Y., Richards, M. A., Lithgow-Bertelloni, C. and Le Stunff, Y.: A geodynamic model of mantle density heterogenity, J. Geophys. Res., 98, 21895–21909, 1993.
Ricard, Y., Mattern, E., and Matas, J.: Synthetic Tomographic Images of Slabs from Mineral Physics, in van der Hilst, R. D., Bass, J. D., Matas, J., and Trampert, J., Changing Views on the Structure, Composition, and Evolution of Earth's Deep Mantle, 285–302, Am. Geophys. Un., 2005.
Richards, M. R. and Engebretson, D. C.: Large-scale mantle convection and the history of subduction, Nature, 355, 437–440, 1992.
Ritsema, J. and van Heijst, H. J.: Seismic imaging of structural heterogeneity in Earth's mantle: Evidence for large-scale mantle flow, Sci. Progr., 83, 243–259, 2000.
Ritsema, J., Deuss, A., van Heijst, H. J., and Woodhouse, J. H.: S40RTS: a degree-40 shear-velocity model for the mantle from new Rayleigh wave dispersion, teleseismic traveltime and normal-mode splitting function measurements, Geophys. J. Int., 184, 1223–1236, 2011.
Schuberth, B. S. A., Bunge, H.-P, and Ritsema, J.: Tomographic filtering of high-resolution mantle circulation models: Can seismic heterogeneity be explained by temperature alone?, Geochem. Geophys. Geosyst., 10, Q05W03, https://doi.org/10.1029/2009GC002401, 2009.
Shephard, G. E., Bunge, H.-P., Schuberth, B. S. A., Müller, R. D., Talsma, A. S., Moder, C., and Landgrebe, T. C. W.: Testing absolute plate reference frames and the implications for the generation of geodynamic mantle heterogeneity structure, Earth Planet. Sci. Lett., 317–318, 204–217, 2012.
Sigloch, K.: Mantle provinces under North America from multifrequency P wave tomography, Geochem. Geophys. Geosys., 12, Q02W08, https://doi.org/10.1029/2010GC003421, 2011.
Simmons, N. A., Forte, A. M., and Grand, S. P.: Joint seismic, geodynamic and mineral physical constraints on three-dimensional mantle heterogeneity: Implications for the relative importance of thermal versus compositional heterogeneity, Geophys. J. Int., 177, 1284–1304, 2009.
Steinberger, B.: Slabs in the lower mantle – results of dynamic modelling compared with tomographic images and the geoid, Phys. Earth Planet. Int., 118, 241–257, 2000.
Steinberger, B. and Antretter, M.: Conduit diameter and buoyant rising speed of mantle plumes: Implications for the motion of hotspots and shape of plume conduits, Geochem. Geophys. Geosyst., 7, Q11018, https://doi.org/10.1029/2006GC001409, 2006.
Steinberger, B. and Calderwood, A.: Models of large-scale viscous flow in the Earth's mantle with constraints from mineral physics and surface observations, Geophys. J. Int., 167, 1461–1481, 2006.
Steinberger, B. and Torsvik, T. H.: Absolute plate motions and true polar wander in the absence of hotspot tracks, Nature, 452, 620–623, 2008.
Steinberger, B. and Torsvik, T. H.: Toward an explanation for the present and past locations of the poles, Geochem. Geophys. Geosyst., 11, Q06W06, https://doi.org/10.1029/2009GC002889, 2010.
Steinberger, B. and Torsvik, T. H.: A geodynamic models of plumes from the margins of Large Low Shear Velocity Provinces, Geochem. Geophys. Geosys., 13, Q01W09, https://doi.org/10.1029/2011GC003808, 2012.
Stixrude, L. and Lithgow-Bertelloni, C.: Thermodynamics of the Earth's Mantle, Rev. Mineral. Geochem., 71, 465–484, 2010.
Torsvik, T. H., Smethurst, M. A., Burke, K., and Steinberger, B.: Large igneous provinces generated from the margins of the large low-velocity provinces in the deep mantle, Geophys. J. Int., 167, 1447–1460, 2006.
Torsvik, T. H., Müller, R. D., van der Voo, R., Steinberger, B., and Gaina, C.: Global plate motion frames: Toward a unified model, Rev. Geophys., 46, RG3004, https://doi.org/10.1029/2007RG000227, 2008.
Torsvik, T. H., Burke, K., Steinberger, B., Webb, S. J., and Ashwal, L. D.: Diamonds sampled by plumes from the core-mantle boundary, Nature, 466, 352–355, 2010.
van der Hilst, R. D., Widiyantoro, S. and Engdahl, E. R.: Evidence for deep mantle circulation from global tomography, Nature, 386, 578–584, 1997.
van der Meer, D., Spakman, W., van Hinsbergen, D. J. J., Amaru, M. L., and Torsvik, T. H.: Towards absolute plate motions constrained by lower-mantle slab remnants, Nat. Geosci., 3, 36–40, 2010.
van der Voo, R., Spakman, W., and Bijwaard, H.: Mesozoic subducted slabs under Siberia, Nature, 397, 246–249, 1999.
Wessel, P. and Smith, W. H. F.: New, improved version of the Generic Mapping Tools released, Eos Trans. AGU, 79, 579, 1998.
Yoshida, M. and Nakakuki, T.: Effects on the long-wavelength geoid anomaly of lateral viscosity variations caused by stiff subducting slabs, weak plate margins and lower mantle rheology, Phys. Earth Planet. Int., 172, 278–288, 2008.
Zhang, N., Zhong, S., Leng, W., and Li, Z.-X.: A model for the evolution of the Earth's mantle structure since the Early Paleozoic, J. Geophys. Res., 115, B06401, https://doi.org/10.1029/2009JB006896, 2010.