Articles | Volume 12, issue 7
https://doi.org/10.5194/se-12-1601-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/se-12-1601-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Comparing global seismic tomography models using varimax principal component analysis
Olivier de Viron
CORRESPONDING AUTHOR
Littoral, Environnement et Sociétés (LIENSs UMR7266 La Rochelle University – CNRS), 17 000 La Rochelle, Charente Maritime, France
Michel Van Camp
Royal Observatory of Belgium, 1180, Brussels, Belgium
Alexia Grabkowiak
Institut de Physique du Globe de Paris, University Paris Diderot, 75 013 Paris, France
Ana M. G. Ferreira
Department of Earth Sciences, University College London, London WC1E 6BT, United Kingdom
CERIS, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisbon, Portugal
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We explain how the extreme 2015–2016 El Niño event lengthened the day by 0.8 ms. The 2015–2016 event was an El Niño event of a different type compared to previous extreme events; thus, we expected different mechanisms of coupling with the solid Earth. We showed that the atmospheric torque on the American topography, usually acting alone during classical El Niños, was, in 2015–2016, augmented by a friction torque over the Pacific Ocean and inherent to the different nature of this particular event.
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Roberto Cabieces, Mariano S. Arnaiz-Rodríguez, Antonio Villaseñor, Elizabeth Berg, Andrés Olivar-Castaño, Sergi Ventosa, and Ana M. G. Ferreira
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Related subject area
Subject area: Core and mantle structure and dynamics | Editorial team: Geodynamics and quantitative modelling | Discipline: Geodynamics
ECOMAN: an open-source package for geodynamic and seismological modelling of mechanical anisotropy
Quantifying mantle mixing through configurational entropy
On the impact of true polar wander on heat flux patterns at the core–mantle boundary
Modeling liquid transport in the Earth's mantle as two-phase flow: effect of an enforced positive porosity on liquid flow and mass conservation
Transport mechanisms of hydrothermal convection in faulted tight sandstones
Influence of heterogeneous thermal conductivity on the long-term evolution of the lower-mantle thermochemical structure: implications for primordial reservoirs
On the choice of finite element for applications in geodynamics
Coupled dynamics and evolution of primordial and recycled heterogeneity in Earth's lower mantle
Manuele Faccenda, Brandon P. VanderBeek, Albert de Montserrat, Jianfeng Yang, Francesco Rappisi, and Neil Ribe
Solid Earth, 15, 1241–1264, https://doi.org/10.5194/se-15-1241-2024, https://doi.org/10.5194/se-15-1241-2024, 2024
Short summary
Short summary
The Earth's internal dynamics and structure can be well understood by combining seismological and geodynamic modelling 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.
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
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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.
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
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Changyeol Lee, Nestor G. Cerpa, Dongwoo Han, and Ikuko Wada
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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.
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
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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.
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
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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.
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
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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.
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.
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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.
As the travel time of seismic waves depends on the Earth's interior properties, seismic...