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Vilacís B, Hayek JN, Stotz IL, Bunge HP, Friedrich AM, Carena S, Clark S. Evidence for active upper mantle flow in the Atlantic and Indo-Australian realms since the Upper Jurassic from hiatus maps and spreading rate changes. Proc Math Phys Eng Sci 2022; 478:20210764. [PMID: 35756875 PMCID: PMC9199074 DOI: 10.1098/rspa.2021.0764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 05/12/2022] [Indexed: 11/12/2022] Open
Abstract
Histories of large-scale horizontal and vertical lithosphere motion hold important information on mantle convection. Here, we compare continent-scale hiatus maps as a proxy for mantle flow induced dynamic topography and plate motion variations in the Atlantic and Indo-Australian realms since the Upper Jurassic, finding they frequently correlate, except when plate boundary forces may play a significant role. This correlation agrees with descriptions of asthenosphere flow beneath tectonic plates in terms of Poiseuille/Couette flow, as it explicitly relates plate motion changes, induced by evolving basal shear forces, to non-isostatic vertical motion of the lithosphere. Our analysis reveals a timescale, on the order of a geological series, between the occurrence of continent-scale hiatus and plate motion changes. This is consistent with the presence of a weak upper mantle. It also shows a spatial scale for interregional hiatus, on the order of 2000-3000 km in diameter, which can be linked by fluid dynamic analysis to active upper mantle flow regions. Our results suggest future studies should pursue large-scale horizontal and vertical lithosphere motion in combination, to track the expressions of past mantle flow. Such studies would provide powerful constraints for adjoint-based geodynamic inverse models of past mantle convection.
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Affiliation(s)
- Berta Vilacís
- Department of Earth and Environmental Sciences, Ludwig-Maximilians-Universität München, Theresienstraße 41 and Luisenstraße 37, Munich 80333 Germany
| | - Jorge N Hayek
- Department of Earth and Environmental Sciences, Ludwig-Maximilians-Universität München, Theresienstraße 41 and Luisenstraße 37, Munich 80333 Germany
| | - Ingo L Stotz
- Department of Earth and Environmental Sciences, Ludwig-Maximilians-Universität München, Theresienstraße 41 and Luisenstraße 37, Munich 80333 Germany
| | - Hans-Peter Bunge
- Department of Earth and Environmental Sciences, Ludwig-Maximilians-Universität München, Theresienstraße 41 and Luisenstraße 37, Munich 80333 Germany
| | - Anke M Friedrich
- Department of Earth and Environmental Sciences, Ludwig-Maximilians-Universität München, Theresienstraße 41 and Luisenstraße 37, Munich 80333 Germany
| | - Sara Carena
- Department of Earth and Environmental Sciences, Ludwig-Maximilians-Universität München, Theresienstraße 41 and Luisenstraße 37, Munich 80333 Germany
| | - Stuart Clark
- University of New South Wales Sydney, Minerals and Energy Res. Eng., Kensington, New South Wales 2052, Australia
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A rapid burst in hotspot motion through the interaction of tectonics and deep mantle flow. Nature 2016; 533:239-42. [PMID: 27172048 DOI: 10.1038/nature17422] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Accepted: 02/09/2016] [Indexed: 11/08/2022]
Abstract
Volcanic hotspot tracks featuring linear progressions in the age of volcanism are typical surface expressions of plate tectonic movement on top of narrow plumes of hot material within Earth's mantle. Seismic imaging reveals that these plumes can be of deep origin--probably rooted on thermochemical structures in the lower mantle. Although palaeomagnetic and radiometric age data suggest that mantle flow can advect plume conduits laterally, the flow dynamics underlying the formation of the sharp bend occurring only in the Hawaiian-Emperor hotspot track in the Pacific Ocean remains enigmatic. Here we present palaeogeographically constrained numerical models of thermochemical convection and demonstrate that flow in the deep lower mantle under the north Pacific was anomalously vigorous between 100 million years ago and 50 million years ago as a consequence of long-lasting subduction systems, unlike those in the south Pacific. These models show a sharp bend in the Hawaiian-Emperor hotspot track arising from the interplay of plume tilt and the lateral advection of plume sources. The different trajectories of the Hawaiian and Louisville hotspot tracks arise from asymmetric deformation of thermochemical structures under the Pacific between 100 million years ago and 50 million years ago. This asymmetric deformation waned just before the Hawaiian-Emperor bend developed, owing to flow in the deepest lower mantle associated with slab descent in the north and south Pacific.
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Hilt M, Glässl M, Zimmermann W. Effects of a temperature-dependent viscosity on thermal convection in binary mixtures. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2014; 89:052312. [PMID: 25353805 DOI: 10.1103/physreve.89.052312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Indexed: 06/04/2023]
Abstract
We investigate the effect of a temperature-dependent viscosity on the onset of thermal convection in a horizontal layer of a binary fluid mixture that is heated from below. For an exponential temperature dependence of the viscosity, we find, in binary mixtures as a function of a positive separation ratio ψ and beyond a certain viscosity contrast, a discontinuous transition between two stationary convection modes having different wavelengths. In the range of negative values of the separation ratio ψ, a (continuous or discontinuous) transition from an oscillatory to a stationary onset of convection occurs beyond a certain viscosity contrast, and for large values of the viscosity ratio, the oscillatory onset of convection is suppressed.
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Affiliation(s)
- Markus Hilt
- Theoretische Physik I, Universität Bayreuth, 95440 Bayreuth, Germany
| | - Martin Glässl
- Theoretische Physik I, Universität Bayreuth, 95440 Bayreuth, Germany
| | - Walter Zimmermann
- Theoretische Physik I, Universität Bayreuth, 95440 Bayreuth, Germany
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Glässl M, Hilt M, Zimmermann W. Convection in colloidal suspensions with particle-concentration-dependent viscosity. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2010; 32:265-272. [PMID: 20676720 DOI: 10.1140/epje/i2010-10652-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2010] [Revised: 06/14/2010] [Accepted: 06/17/2010] [Indexed: 05/29/2023]
Abstract
The onset of thermal convection in a horizontal layer of a colloidal suspension is investigated in terms of a continuum model for binary-fluid mixtures where the viscosity depends on the local concentration of colloidal particles. With an increasing difference between the viscosity at the warmer and the colder boundary the threshold of convection is reduced in the range of positive values of the separation ratio psi with the onset of stationary convection as well as in the range of negative values of psi with an oscillatory Hopf bifurcation. Additionally the convection rolls are shifted downwards with respect to the center of the horizontal layer for stationary convection psi>0 and upwards for the Hopf bifurcation (psi<0.
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Affiliation(s)
- M Glässl
- Theoretische Physik I, Universität Bayreuth, 95440, Bayreuth, Germany
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Hernlund JW, Tackley PJ, Stevenson DJ. Buoyant melting instabilities beneath extending lithosphere: 1. Numerical models. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2006jb004862] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Tan E, Gurnis M. Compressible thermochemical convection and application to lower mantle structures. ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2006jb004505] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Roberts JH, Zhong S. Degree-1 convection in the Martian mantle and the origin of the hemispheric dichotomy. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2005je002668] [Citation(s) in RCA: 119] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Xie S, Tackley PJ. Evolution of U-Pb and Sm-Nd systems in numerical models of mantle convection and plate tectonics. ACTA ACUST UNITED AC 2004. [DOI: 10.1029/2004jb003176] [Citation(s) in RCA: 110] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Shunxing Xie
- Department of Earth and Space Sciences; University of California; Los Angeles California USA
| | - Paul J. Tackley
- Department of Earth and Space Sciences and Institute of Geophysics and Planetary Physics; University of California; Los Angeles California USA
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McNamara AK, Zhong S. Thermochemical structures within a spherical mantle: Superplumes or piles? ACTA ACUST UNITED AC 2004. [DOI: 10.1029/2003jb002847] [Citation(s) in RCA: 185] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
| | - Shijie Zhong
- Department of Physics; University of Colorado; Boulder Colorado USA
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Stegman DR, Jellinek AM, Zatman SA, Baumgardner JR, Richards MA. An early lunar core dynamo driven by thermochemical mantle convection. Nature 2003; 421:143-6. [PMID: 12520295 DOI: 10.1038/nature01267] [Citation(s) in RCA: 149] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2002] [Accepted: 10/25/2002] [Indexed: 11/10/2022]
Abstract
Although the Moon currently has no internally generated magnetic field, palaeomagnetic data, combined with radiometric ages of Apollo samples, provide evidence for such a magnetic field from approximately 3.9 to 3.6 billion years (Gyr) ago, possibly owing to an ancient lunar dynamo. But the presence of a lunar dynamo during this time period is difficult to explain, because thermal evolution models for the Moon yield insufficient core heat flux to power a dynamo after approximately 4.2 Gyr ago. Here we show that a transient increase in core heat flux after an overturn of an initially stratified lunar mantle might explain the existence and timing of an early lunar dynamo. Using a three-dimensional spherical convection model, we show that a dense layer, enriched in radioactive elements (a 'thermal blanket'), at the base of the lunar mantle can initially prevent core cooling, thereby inhibiting core convection and magnetic field generation. Subsequent radioactive heating progressively increases the buoyancy of the thermal blanket, ultimately causing it to rise back into the mantle. The removal of the thermal blanket, proposed to explain the eruption of thorium- and titanium-rich lunar mare basalts, plausibly results in a core heat flux sufficient to power a short-lived lunar dynamo.
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Affiliation(s)
- Dave R Stegman
- Department of Earth and Planetary Science, University of California, Berkeley, California 94720, USA.
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Tackley PJ, Xie S. The thermochemical structure and evolution of Earth's mantle: constraints and numerical models. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2002; 360:2593-2609. [PMID: 12460482 DOI: 10.1098/rsta.2002.1082] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Geochemical observations place several constraints on geophysical processes in the mantle, including a requirement to maintain several distinct reservoirs. Geophysical constraints limit plausible physical locations of these reservoirs to a thin basal layer, isolated deep 'piles' of material under large-scale mantle upwellings, high-viscosity blobs/plums or thin strips throughout the mantle, or some combination of these. A numerical model capable of simulating the thermochemical evolution of the mantle is introduced. Preliminary simulations are more differentiated than Earth but display some of the proposed thermochemical processes, including the generation of a high-mu mantle reservoir by recycling of crust, and the generation of a high-(3)He/(4)He reservoir by recycling of residuum, although the resulting high-(3)He/(4)He material tends to aggregate near the top, where mid-ocean-ridge melting should sample it. If primitive material exists as a dense basal layer, it must be much denser than subducted crust in order to retain its primitive (e.g. high-(3)He) signature. Much progress is expected in the near future.
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Affiliation(s)
- Paul J Tackley
- Department of Earth and Space Sciences and Institute of Geophysics and Planetary Physics, University of California, Los Angeles, 595 Charles Young Drive East, 90095-1567, USA.
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Zhong S, Zuber MT, Moresi L, Gurnis M. Role of temperature-dependent viscosity and surface plates in spherical shell models of mantle convection. ACTA ACUST UNITED AC 2000. [DOI: 10.1029/2000jb900003] [Citation(s) in RCA: 453] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Wenk HR, Baumgardner JR, Lebensohn RA, Tomé CN. A convection model to explain anisotropy of the inner core. ACTA ACUST UNITED AC 2000. [DOI: 10.1029/1999jb900346] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Butler SL, Peltier WR. On scaling relations in time-dependent mantle convection and the heat transfer constraint on layering. ACTA ACUST UNITED AC 2000. [DOI: 10.1029/1999jb900377] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Bercovici D, Ricard Y, Richards MA. The Relation between mantle dynamics and plate tectonics: A Primer. GEOPHYSICAL MONOGRAPH SERIES 2000. [DOI: 10.1029/gm121p0005] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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The Quest for self-consistent generation of plate tectonics in mantle convection models. ACTA ACUST UNITED AC 2000. [DOI: 10.1029/gm121p0047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Moore WB, Schubert G, Tackley P. Three-dimensional simulations of plume-lithosphere interaction at the hawaiian swell. Science 1998; 279:1008-11. [PMID: 9461428 DOI: 10.1126/science.279.5353.1008] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Rapid lithospheric thinning by mantle plumes has not been achieved in numerical experiments performed to date. Efficient thinning depends on small-scale instabilities that convectively remove lithospheric material. These instabilities are favored by hotter plumes or stronger temperature dependence of viscosity, and a simple scaling independent of rheology controls their onset. This scaling allows extrapolation of the results of numerical experiments to the Earth's mantle. Mantle plumes between 100 and 150 kelvins hotter than the background mantle should exhibit small-scale convective rolls aligned with the plate motion. The unusual variation in heat flow across the Hawaiian swell may be due to such instabilities. It was found that the spreading of the plume creates a downwelling curtain of material that isolates it from the rest of the mantle for distances of at least 1000 kilometers from the plume origin. This isolation has important consequences for the geochemical heterogeneity of the lithosphere and upper mantle.
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Affiliation(s)
- WB Moore
- W. B. Moore and P. J. Tackley, Department of Earth and Space Sciences, University of California, Los Angeles, 3806 Geology Building, Los Angeles, CA 90095-1567, USA. G. Schubert, Department of Earth and Space Sciences and Institute of G
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Tackley PJ. Three-dimensional simulations of mantle convection with a thermo-chemical basal boundary layer: D″? THE CORE‐MANTLE BOUNDARY REGION 1998. [DOI: 10.1029/gd028p0231] [Citation(s) in RCA: 141] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Bunge HP, Richards MA, Baumgardner JR. A sensitivity study of three-dimensional spherical mantle convection at 108Rayleigh number: Effects of depth-dependent viscosity, heating mode, and an endothermic phase change. ACTA ACUST UNITED AC 1997. [DOI: 10.1029/96jb03806] [Citation(s) in RCA: 214] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Ratcliff JT, Schubert G, Zebib A. Steady tetrahedral and cubic patterns of spherical shell convection with temperature-dependent viscosity. ACTA ACUST UNITED AC 1996. [DOI: 10.1029/96jb02097] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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