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Cathles L, Fjeldskar W, Lenardic A, Romanowicz B, Seales J, Richards M. Influence of the asthenosphere on earth dynamics and evolution. Sci Rep 2023; 13:13367. [PMID: 37591899 PMCID: PMC10435468 DOI: 10.1038/s41598-023-39973-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 08/02/2023] [Indexed: 08/19/2023] Open
Abstract
The existence of a thin, weak asthenospheric layer beneath Earth's lithospheric plates is consistent with existing geological and geophysical constraints, including Pleistocene glacio-isostatic adjustment, modeling of gravity anomalies, studies of seismic anisotropy, and post-seismic rebound. Mantle convection models suggest that a pronounced weak zone beneath the upper thermal boundary layer (lithosphere) may be essential to the plate tectonic style of convection found on Earth. The asthenosphere is likely related to partial melting and the presence of water in the sub-lithospheric mantle, further implying that the long-term evolution of the Earth may be controlled by thermal regulation and volatile recycling that maintain a geotherm that approaches the wet mantle solidus at asthenospheric depths.
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Affiliation(s)
- Lawrence Cathles
- Department of Earth and Atmospheric Sciences, Cornell University, Ithaca, USA
| | | | | | - Barbara Romanowicz
- Department of Earth and Planetary Science, University of California, Berkeley, USA
| | - Johnny Seales
- Department of Earth Science, Rice University, Houston, USA
| | - Mark Richards
- Department of Earth and Space Sciences, University of Washington, Seattle, USA
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Platz T, Byrne PK, Massironi M, Hiesinger H. Volcanism and tectonism across the inner solar system: an overview. ACTA ACUST UNITED AC 2014. [DOI: 10.1144/sp401.22] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
AbstractVolcanism and tectonism are the dominant endogenic means by which planetary surfaces change. This book, in general, and this overview, in particular, aim to encompass the broad range in character of volcanism, tectonism, faulting and associated interactions observed on planetary bodies across the inner solar system – a region that includes Mercury, Venus, Earth, the Moon, Mars and asteroids. The diversity and breadth of landforms produced by volcanic and tectonic processes are enormous, and vary across the inventory of inner solar system bodies. As a result, the selection of prevailing landforms and their underlying formational processes that are described and highlighted in this review are but a primer to the expansive field of planetary volcanism and tectonism. In addition to this extended introductory contribution, this Special Publication features 21 dedicated research articles about volcanic and tectonic processes manifest across the inner solar system. Those articles are summarized at the end of this review.
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Affiliation(s)
- T. Platz
- Planetary Science Institute, 1700 East Fort Lowell Road, Tucson, AZ 85719-2395, USA
- Freie Universität Berlin, Institute of Geological Sciences, Planetary Sciences & Remote Sensing, Malteserstrasse 74-100, 12249 Berlin, Germany
| | - P. K. Byrne
- Lunar and Planetary Institute, Universities Space Research Association, 3600 Bay Area Boulevard, Houston, TX 77058, USA
- Department of Terrestrial Magnetism, Carnegie Institution of Washington, 5241 Broad Branch Road NW, Washington, DC 20015-1305, USA
| | - M. Massironi
- Dipartimento di Geoscienze, Universita' degli Studi di Padova, via G. Gradenigo 6, 35131 Padova, Italy
| | - H. Hiesinger
- Institut für Planetologie, Westfälische Wilhelms-Universität Münster, Wilhelm-Klemm-Strasse 10, 48149 Münster, Germany
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Beghein C, Yuan K, Schmerr N, Xing Z. Changes in seismic anisotropy shed light on the nature of the Gutenberg discontinuity. Science 2014; 343:1237-40. [PMID: 24578529 DOI: 10.1126/science.1246724] [Citation(s) in RCA: 92] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The boundary between the lithosphere and asthenosphere is associated with a platewide high-seismic velocity "lid" overlying lowered velocities, consistent with thermal models. Seismic body waves also intermittently detect a sharp velocity reduction at similar depths, the Gutenberg (G) discontinuity, which cannot be explained by temperature alone. We compared an anisotropic tomography model with detections of the G to evaluate their context and relation to the lithosphere-asthenosphere boundary (LAB). We find that the G is primarily associated with vertical changes in azimuthal anisotropy and lies above a thermally controlled LAB, implying that the two are not equivalent interfaces. The origin of the G is a result of frozen-in lithospheric structures, regional compositional variations of the mantle, or dynamically perturbed LAB.
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Affiliation(s)
- Caroline Beghein
- Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, 595 Charles Young Drive East, Box 951567, Los Angeles, CA 90095-1567, USA
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Zhu H, Tromp J. Mapping Tectonic Deformation in the Crust and Upper Mantle Beneath Europe and the North Atlantic Ocean. Science 2013; 341:871-5. [PMID: 23929947 DOI: 10.1126/science.1241335] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Hejun Zhu
- Department of Geosciences, Princeton University, Princeton, NJ, USA
| | - Jeroen Tromp
- Department of Geosciences, Princeton University, Princeton, NJ, USA
- Program in Applied and Computational Mathematics, Princeton University, Princeton, NJ, USA
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Lithospheric layering in the North American craton. Nature 2010; 466:1063-8. [PMID: 20740006 DOI: 10.1038/nature09332] [Citation(s) in RCA: 377] [Impact Index Per Article: 26.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2009] [Accepted: 06/25/2010] [Indexed: 11/09/2022]
Abstract
How cratons-extremely stable continental areas of the Earth's crust-formed and remained largely unchanged for more than 2,500 million years is much debated. Recent studies of seismic-wave receiver function data have detected a structural boundary under continental cratons at depths too shallow to be consistent with the lithosphere-asthenosphere boundary, as inferred from seismic tomography and other geophysical studies. Here we show that changes in the direction of azimuthal anisotropy with depth reveal the presence of two distinct lithospheric layers throughout the stable part of the North American continent. The top layer is thick ( approximately 150 km) under the Archaean core and tapers out on the surrounding Palaeozoic borders. Its thickness variations follow those of a highly depleted layer inferred from thermo-barometric analysis of xenoliths. The lithosphere-asthenosphere boundary is relatively flat (ranging from 180 to 240 km in depth), in agreement with the presence of a thermal conductive root that subsequently formed around the depleted chemical layer. Our findings tie together seismological, geochemical and geodynamical studies of the cratonic lithosphere in North America. They also suggest that the horizon detected in receiver function studies probably corresponds to the sharp mid-lithospheric boundary rather than to the more gradual lithosphere-asthenosphere boundary.
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Kreemer C. Absolute plate motions constrained by shear wave splitting orientations with implications for hot spot motions and mantle flow. ACTA ACUST UNITED AC 2009. [DOI: 10.1029/2009jb006416] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Kawakatsu H, Kumar P, Takei Y, Shinohara M, Kanazawa T, Araki E, Suyehiro K. Seismic evidence for sharp lithosphere-asthenosphere boundaries of oceanic plates. Science 2009; 324:499-502. [PMID: 19390042 DOI: 10.1126/science.1169499] [Citation(s) in RCA: 411] [Impact Index Per Article: 27.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The mobility of the lithosphere over a weaker asthenosphere constitutes the essential element of plate tectonics, and thus the understanding of the processes at the lithosphere-asthenosphere boundary (LAB) is fundamental to understand how our planet works. It is especially so for oceanic plates because their relatively simple creation and evolution should enable easy elucidation of the LAB. Data from borehole broadband ocean bottom seismometers show that the LAB beneath the Pacific and Philippine Sea plates is sharp and age-dependent. The observed large shear wave velocity reduction at the LAB requires a partially molten asthenosphere consisting of horizontal melt-rich layers embedded in meltless mantle, which accounts for the large viscosity contrast at the LAB that facilitates horizontal plate motions.
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Affiliation(s)
- Hitoshi Kawakatsu
- Earthquake Research Institute, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan.
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Affiliation(s)
- Barbara Romanowicz
- Berkeley Seismological Laboratory and Department of Earth and Planetary Science, University of California at Berkeley, Berkeley, CA 94720, USA
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Bagley B, Revenaugh J. Upper mantle seismic shear discontinuities of the Pacific. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2008jb005692] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Kustowski B, Ekström G, Dziewoński AM. Anisotropic shear-wave velocity structure of the Earth's mantle: A global model. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2007jb005169] [Citation(s) in RCA: 397] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Conrad CP, Behn MD, Silver PG. Global mantle flow and the development of seismic anisotropy: Differences between the oceanic and continental upper mantle. ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2006jb004608] [Citation(s) in RCA: 121] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Marone F, Romanowicz B. The depth distribution of azimuthal anisotropy in the continental upper mantle. Nature 2007; 447:198-201. [PMID: 17495924 DOI: 10.1038/nature05742] [Citation(s) in RCA: 123] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2006] [Accepted: 03/08/2007] [Indexed: 11/08/2022]
Abstract
The most likely cause of seismic anisotropy in the Earth's upper mantle is the lattice preferred orientation of anisotropic minerals such as olivine. Its presence reflects dynamic processes related to formation of the lithosphere as well as to present-day tectonic motions. A powerful tool for detecting and characterizing upper-mantle anisotropy is the analysis of shear-wave splitting measurements. Because of the poor vertical resolution afforded by this type of data, however, it has remained controversial whether the splitting has a lithospheric origin that is 'frozen-in' at the time of formation of the craton, or whether the anisotropy originates primarily in the asthenosphere, and is induced by shear owing to present-day absolute plate motions. In addition, predictions from surface-wave-derived models are largely incompatible with shear-wave splitting observations. Here we show that this disagreement can be resolved by simultaneously inverting surface waveforms and shear-wave splitting data. We present evidence for the presence of two layers of anisotropy with different fast-axis orientations in the cratonic part of the North American upper mantle. At asthenospheric depths (200-400 km) the fast axis is sub-parallel to the absolute plate motion, confirming the presence of shear related to current tectonic processes, whereas in the lithosphere (80-200 km), the orientation is significantly more northerly. In the western, tectonically active, part of North America, the fast-axis direction is consistent with the absolute plate motion throughout the depth range considered, in agreement with a much thinner lithosphere.
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Affiliation(s)
- Federica Marone
- Berkeley Seismological Laboratory, 209 McCone Hall, Berkeley, California 94720, USA
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Zhou Y, Nolet G, Dahlen FA, Laske G. Global upper-mantle structure from finite-frequency surface-wave tomography. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2005jb003677] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Hammond JOS, Kendall JM, Rümpker G, Wookey J, Teanby N, Joseph P, Ryberg T, Stuart G. Upper mantle anisotropy beneath the Seychelles microcontinent. ACTA ACUST UNITED AC 2005. [DOI: 10.1029/2005jb003757] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- J. O. S. Hammond
- School of Earth and Environment, Earth Science; University of Leeds; Leeds UK
| | - J.-M. Kendall
- School of Earth and Environment, Earth Science; University of Leeds; Leeds UK
| | - G. Rümpker
- GeoForschungsZentrum Potsdam; Potsdam Germany
- Arbeitsbereich Geophysik; Johann Wolfgang Goethe-Universitat; Frankfurt am Main Germany
| | - J. Wookey
- School of Earth and Environment, Earth Science; University of Leeds; Leeds UK
| | - N. Teanby
- School of Earth and Environment, Earth Science; University of Leeds; Leeds UK
- Atmospheric, Oceanic and Planetary Physics; University of Oxford, Clarendon Laboratory; Oxford UK
| | - P. Joseph
- Seychelles National Oil Company; Victoria, Mahé Seychelles
| | - T. Ryberg
- GeoForschungsZentrum Potsdam; Potsdam Germany
| | - G. Stuart
- School of Earth and Environment, Earth Science; University of Leeds; Leeds UK
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Mainprice D, Tommasi A, Couvy H, Cordier P, Frost DJ. Pressure sensitivity of olivine slip systems and seismic anisotropy of Earth's upper mantle. Nature 2005; 433:731-3. [PMID: 15716950 DOI: 10.1038/nature03266] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2004] [Accepted: 11/30/2004] [Indexed: 11/08/2022]
Abstract
The mineral olivine dominates the composition of the Earth's upper mantle and hence controls its mechanical behaviour and seismic anisotropy. Experiments at high temperature and moderate pressure, and extensive data on naturally deformed mantle rocks, have led to the conclusion that olivine at upper-mantle conditions deforms essentially by dislocation creep with dominant [100] slip. The resulting crystal preferred orientation has been used extensively to explain the strong seismic anisotropy observed down to 250 km depth. The rapid decrease of anisotropy below this depth has been interpreted as marking the transition from dislocation to diffusion creep in the upper mantle. But new high-pressure experiments suggest that dislocation creep also dominates in the lower part of the upper mantle, but with a different slip direction. Here we show that this high-pressure dislocation creep produces crystal preferred orientations resulting in extremely low seismic anisotropy, consistent with seismological observations below 250 km depth. These results raise new questions about the mechanical state of the lower part of the upper mantle and its coupling with layers both above and below.
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Affiliation(s)
- David Mainprice
- Laboratoire de Tectonophysique, CNRS/Université de Montpellier II, F-34095 Montpellier cedex 5, France.
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Debayle E, Kennett B, Priestley K. Global azimuthal seismic anisotropy and the unique plate-motion deformation of Australia. Nature 2005; 433:509-12. [PMID: 15690038 DOI: 10.1038/nature03247] [Citation(s) in RCA: 230] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2004] [Accepted: 11/29/2004] [Indexed: 11/08/2022]
Abstract
Differences in the thickness of the high-velocity lid underlying continents as imaged by seismic tomography, have fuelled a long debate on the origin of the 'roots' of continents. Some of these differences may be reconciled by observations of radial anisotropy between 250 and 300 km depth, with horizontally polarized shear waves travelling faster than vertically polarized ones. This azimuthally averaged anisotropy could arise from present-day deformation at the base of the plate, as has been found for shallower depths beneath ocean basins. Such deformation would also produce significant azimuthal variation, owing to the preferred alignment of highly anisotropic minerals. Here we report global observations of surface-wave azimuthal anisotropy, which indicate that only the continental portion of the Australian plate displays significant azimuthal anisotropy and strong correlation with present-day plate motion in the depth range 175-300 km. Beneath other continents, azimuthal anisotropy is only weakly correlated with plate motion and its depth location is similar to that found beneath oceans. We infer that the fast-moving Australian plate contains the only continental region with a sufficiently large deformation at its base to be transformed into azimuthal anisotropy. Simple shear leading to anisotropy with a plunging axis of symmetry may explain the smaller azimuthal anisotropy beneath other continents.
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Affiliation(s)
- Eric Debayle
- Institut de Physique du Globe de Strasbourg, Ecole et Observatoire des Sciences de la Terre, Centre National de la Recherche Scientifique and Université Louis Pasteur, 61084 Strasbourg, Cedex, France.
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Cammarano F. One-dimensional physical reference models for the upper mantle and transition zone: Combining seismic and mineral physics constraints. ACTA ACUST UNITED AC 2005. [DOI: 10.1029/2004jb003272] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Stixrude L. Mineralogy and elasticity of the oceanic upper mantle: Origin of the low-velocity zone. ACTA ACUST UNITED AC 2005. [DOI: 10.1029/2004jb002965] [Citation(s) in RCA: 212] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Affiliation(s)
- Jeroen Ritsema
- Seismological Laboratory; California Institute of Technology; Pasadena California USA
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Panning M, Romanowicz B. Inferences on Flow at the Base of Earth's Mantle Based on Seismic Anisotropy. Science 2004; 303:351-3. [PMID: 14726586 DOI: 10.1126/science.1091524] [Citation(s) in RCA: 173] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
We applied global waveform tomography to model radial anisotropy in the whole mantle. We found that in the last few hundred kilometers near the core-mantle boundary, horizontally polarized S-wave velocities (VSH) are, on average, faster (by approximately 1%) than vertically polarized S-wave velocities (VSV), suggesting a large-scale predominance of horizontal shear. This confirms that the D" region at the base of the mantle is also a mechanical boundary layer for mantle convection. A notable exception to this average signature can be found at the base of the two broad low-velocity regions under the Pacific Ocean and under Africa, often referred to as "superplumes," where the anisotropic pattern indicates the onset of vertical flow.
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Affiliation(s)
- Mark Panning
- Berkeley Seismological Laboratory, 215 McCone Hall, University of California, Berkeley, CA 94720, USA.
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