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Ivins ER, Caron L, Adhikari S, Larour E, Scheinert M. A linear viscoelasticity for decadal to centennial time scale mantle deformation. Rep Prog Phys 2020; 83:106801. [PMID: 32629433 DOI: 10.1088/1361-6633/aba346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The extended Burgers material (EBM) model provides a linear viscoelastic theory for interpreting a variety of rock deformation phenomena in geophysics, playing an increasingly important role in parameterizing laboratory data, providing seismic wave velocity and attenuation interpretations, and in analyses of solid planetary tidal dispersion and quality factor Q. At the heart of the EBM approach is the assumption of a distribution of relaxation spectra tied to rock grain boundary and interior granular mobility. Furthermore, the model incorporates an asymptotic long-term limiting behavior that is Maxwellian. Here we use the extensively developed linear theory of viscoelasticity to isolate those parameters of EBM that apply to both post-seismic relaxation processes involving flow of olivine rich upper mantle material and to studies of tides, where periods of forcing range from 12 h to 18.6 years. The isolated EBM parameters should also apply to theoretical and geodetic studies of glacial isostatic adjustment, especially when the initiation of continuous cryospheric surface unloading dates to the 20th or 21st century. Using analytical Laplace transformed solutions of Boussinesq's half-space load problem, we show that the effects of EBM transient rheology may have substantial influence on geodetic interpretations of unloading induced crustal motions even on time scales that are sub-decadal.
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Affiliation(s)
- E R Ivins
- Jet Propulsion Lab, California Institute of Technology, 4800 Oak Grove Dr., Pasadena, CA, 91109
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Scheinert M, Ferraccioli F, Schwabe J, Bell R, Studinger M, Damaske D, Jokat W, Aleshkova N, Jordan T, Leitchenkov G, Blankenship DD, Damiani TM, Young D, Cochran JR, Richter TD. New Antarctic Gravity Anomaly Grid for Enhanced Geodetic and Geophysical Studies in Antarctica. Geophys Res Lett 2016; 43:600-610. [PMID: 29326484 PMCID: PMC5759340 DOI: 10.1002/2015gl067439] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Gravity surveying is challenging in Antarctica because of its hostile environment and inaccessibility. Nevertheless, many ground-based, airborne and shipborne gravity campaigns have been completed by the geophysical and geodetic communities since the 1980s. We present the first modern Antarctic-wide gravity data compilation derived from 13 million data points covering an area of 10 million km2, which corresponds to 73% coverage of the continent. The remove-compute-restore technique was applied for gridding, which facilitated levelling of the different gravity datasets with respect to an Earth Gravity Model derived from satellite data alone. The resulting free-air and Bouguer gravity anomaly grids of 10 km resolution are publicly available. These grids will enable new high-resolution combined Earth Gravity Models to be derived and represent a major step forward towards solving the geodetic polar data gap problem. They provide a new tool to investigate continental-scale lithospheric structure and geological evolution of Antarctica.
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Affiliation(s)
- M. Scheinert
- Institut für Planetare Geodäsie, Technische Universität Dresden, Dresden, Germany
| | - F. Ferraccioli
- British Antarctic Survey, High Cross, Madingley Road, Cambridge, UK
| | - J. Schwabe
- Institut für Planetare Geodäsie, Technische Universität Dresden, Dresden, Germany
| | - R. Bell
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY, USA
| | | | - D. Damaske
- Bundesanstalt für Geowissenschaften und Rohstoffe, Hannover, Germany
| | - W. Jokat
- Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung, Bremerhaven, Germany
- University of Bremen, Geoscience, Department, Bremen, Germany
| | | | - T. Jordan
- British Antarctic Survey, High Cross, Madingley Road, Cambridge, UK
| | - G. Leitchenkov
- VNIIOkeangeologia, St. Petersburg, Russia
- St. Petersburg State University, St. Petersburg, Russia
| | - D. D. Blankenship
- Institute for Geophysics, Jackson School of Geosciences, University of Texas at Austin, TX, USA
| | - T. M. Damiani
- National Geodetic Survey, NOAA, Silver Spring, MD, USA
| | - D. Young
- Institute for Geophysics, Jackson School of Geosciences, University of Texas at Austin, TX, USA
| | - J. R. Cochran
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY, USA
| | - T. D. Richter
- Institute for Geophysics, Jackson School of Geosciences, University of Texas at Austin, TX, USA
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