Current Science

Open Access Open Access  Restricted Access Subscription Access

Effective Elastic Thickness of the Continental Lithosphere with Particular Reference to the India–Eurasia Collision System


Affiliations
1 CSIR-National Geophysical Research Institute, Hyderabad 500 007, India
 

The effective elastic thickness (EET) of the lithosphere is a measure of the lithosphere’s ability to flex under long-term geological and topographic loads. It is often estimated through analyses of gravity and topographic data. The EET has a significant role in regulating the geodynamic evolution of both the continental and oceanic plates. Estimates of EET derived from geophysical data are consistent with rheological models in the oceanic regions. However, there are extensive debates on the estimates of EET and rheological models over the continental areas; differences are probably due to the complex structure and history of the continental plates. For instance, according to one model of continental rheology, popularly known as the ‘Jelly Sandwich’, the mechanical strength of the lithospheric plate is distributed in the upper crust and the lithospheric mantle. In another model, dubbed as ‘Crème Brulee’, the lithospheric mantle is weak, and the mechanical strength of the lithosphere is limited to the upper portion of the crust. These model differences have arisen because of inconsistent results obtained using different datasets, e.g. the distribution of earthquakes, EET, gravity anomaly and rheology. This article discusses the evolution of these contrasting models and the critical necessity to resolve the model differences.

Keywords

Continental Rheology, Effective Elastic Thickness, Flexural Modelling, Isostasy, Lithosphere.
User
Notifications
Font Size

  • Barrell, J., The strength of the Earth’s crust – Part I. Geologic tests of the limits of strength. J. Geol., 1914, 22, 28–48.

  • Le Pichon, X., Francheteau, J. and Bonnin, J., Plate Tectonics, Developments in Geotectonics, Elsevier, New York, 1973, pp. 7–18.

  • Watts, A. B., Crustal and lithosphere dynamics: an introduction and overview. In Treatise on Geophysics, Elsevier, 2015, pp. 1–48.

  • Pratt, A. and Stokes, G. G., On the deflection of the plumb-line in India caused by the attraction of the Himalaya mountains and the elevated regions beyond, and its modification by the compensating effect of a deficiency of matter below the mountain mass. Proc. R. Soc. London, 1859, 9, 493–496.

  • Hayford, J. F., Geodesy: The Figure of the Earth and Isostasy from Measurements in the United States, US Government Printing Office, Washington, 1909, pp. 66–73.

  • Airy, G. B., On the computation of the effect of the attraction of mountain-masses, as disturbing the apparent astronomical latitude of stations in geodetic surveys. Philos. Trans. R. Soc. London, 1855, 145, 101–104.

  • Heiskanen, W., Isostatic tables for the reduction of gravimetric observations calculated on the basis of Airy’s hypothesis. Bull. Géod., 1931, 30, 110–153.

  • Vening-Meinesz, A. F., Gravity over the Hawaiian Archipelago and over the Madeira area. Proc. Koninklijke Nederlandse Akad. Wetenschappen, 1941, 44, 1–14.

  • Hertz, H., On the equilibrium of floating elastic plates. Wiedmann’s Annalen, 1884, 22, 449–455.

  • Watts, A. B., Isostasy and Flexure of the Lithosphere, Cambridge University Press, Cambridge, 2001, pp. 71–85.

  • Burov, E. B. and Diament, M., The effective elastic thickness (Te) of continental lithosphere: what does it really mean? J. Geophys. Res., 1995, 100, 3905–3927.

  • Lowry, A. R. and Smith, R. B., Flexural rigidity of the Basin and Range-Colorado Plateau-Rocky Mountain transition from coherence analysis of gravity and topography. J. Geophys. Res., 1994, 99, 20123–20140.

  • Watts, A. B. and Burov, E. B., Lithospheric strength and its relationship to the elastic and seismogenic layer thickness. Earth Planet. Sci. Lett., 2003, 213, 113–131.

  • McKenzie, D., Estimating Te in the presence of internal loads. J. Geophys. Res. B, 2003, 108(9), 2438.

  • Burov, E. B. and Watts, A. B., The long-term strength of continental lithosphere: ‘jelly sandwich’ or ‘crème brûlée’? GSA Today, 2006, 16, 4–10.

  • Mouthereau, F., Watts, A. B. and Burov, E. B., Structure of orogenic belts controlled by lithosphere age. Nature Geosci., 2013, 6, 785–789.

  • Mound, J. E., Mitrovica, J. X. and Forte, A. M., The equilibrium form of a rotating earth with an elastic shell. Geophys. J. Int., 2003, 152, 237–241.

  • Shukowsky, W. and Mantovani, M. S. M., Spatial variability of tidal gravity anomalies and its correlation with the effective elastic thickness of the lithosphere. Phys. Earth Planet. Int., 1999, 114, 81–90.

  • Mantovani, M. S. M., Shukowsky, W., de Freitas, S. R. C. and Brito Neves, B. B., Lithosphere mechanical behavior inferred from tidal gravity anomalies: a comparison of Africa and South America. Earth Planet. Sci. Lett., 2005, 230, 397–412.

  • Dyksterhuis, S. and Albert, R. A., Finite-element modelling of contemporary and palaeo-intraplate stress using ABAQUSTM. Comput. Geosci., 2005, 31, 297–307.

  • Tesauro, M., Kaban, M. K. and Cloetingh, S. A. P. L., Global strength and elastic thickness of the lithosphere. Global Planet. Change, 2012, 90–91, 51–57.

  • McNutt, M. K., Lithospheric flexure and thermal anomalies. J. Geo-phys. Res.: Solid Earth, 1984, 89, 11180–11194.

  • Kunnummal, P. and Anand, S. P., Crustal structure and tectonic evolution of Greater Maldive Ridge, Western Indian Ocean, in the context of plume-ridge interaction. Gondwana Res., 2022, 106, 142–163.

  • Kalnins, L. M. and Watts, A. B., Spatial variations in effective elastic thickness in the Western Pacific Ocean and their implications for Mesozoic volcanism. Earth Planet. Sci. Lett., 2009, 286, 89–100.

  • Zhang, F., Lin, J. and Zhan, W., Variations in oceanic plate bending along the Mariana trench. Earth Planet. Sci. Lett., 2014, 401, 206–214.

  • Yang, A. and Fu, Y., Estimates of effective elastic thickness at subduction zones. J. Geodyn., 2018, 117, 75–87.

  • Jordan, T. A. and Watts, A. B., Gravity anomalies, flexure and the elastic thickness structure of the India–Eurasia collisional system. Earth Planet. Sci. Lett., 2005, 236, 732–750.

  • Forsyth, D. W., Subsurface loading and estimates of the flexural rigidity of continental lithosphere. J. Geophys. Res.: Solid Earth, 1985, 90, 12623–12632.

  • McKenzie, D. and Fairhead, D., Estimates of the effective elastic thickness of the continental lithosphere from Bouguer and free air gravity anomalies. J. Geophys. Res.: Solid Earth, 1997, 102, 27523–27552.

  • Cattin, R., Martelet, G., Henry, P., Avouac, J. P., Diament, M. and Shakya, T. R., Gravity anomalies, crustal structure and thermo-mechanical support of the Himalaya of Central Nepal. Geophys. J. Int., 2001, 147, 381–392.

  • Hetényi, G., Cattin, R., Vergne, J. and Nábělek, J. L., The effective elastic thickness of the India Plate from receiver function imaging, gravity anomalies and thermomechanical modelling. Geophys. J. Int., 2006, 167, 1106–1118.

  • Goetze, C. and Evans, B., Stress and temperature in the bending lithosphere as constrained by experimental rock mechanics. Geo-phys. J. Int., 1979, 59, 463–478.

  • Brace, W. F. and Kohlstedt, D. L., Limits on lithospheric stress imposed by laboratory experiments. J. Geophys. Res.: Solid Earth, 1980, 85, 6248–6252.

  • Dorman, L. M. and Lewis, B. T. R., Experimental isostasy: 1. Theory of the determination of the Earth’s isostatic response to a concentrated load. J. Geophys. Res., 1970, 75, 3357–3365.

  • Lewis, B. T. R. and Dorman, L. M., Experimental isostasy: 2. An isostatic model for the U.S.A. derived from gravity and topographic data. J. Geophys. Res., 1970, 75, 3367–3386.

  • Banks, R. J., Parker, R. L. and Huestis, S. P., Isostatic compensation on a continental scale: local versus regional mechanisms. Geophys. J. Int., 1977, 51, 431–452.

  • McNutt, M. K. and Parker, R. L., Isostasy in Australia and the evolution of the compensation mechanism. Science, 1978, 199, 773–775.

  • Bechtel, T. D., Forsyth, D. W., Sharpton, V. L. and Grieve, R. A. F., Variations in effective elastic thickness of the North American lithosphere. Nature, 1990, 343, 636–638.

  • Simons, F. J., Zuber, M. T. and Korenaga, J., Isostatic response of the Australian lithosphere: estimation of effective elastic thickness and anisotropy using multitaper spectral analysis. J. Geophys. Res.: Solid Earth, 2000, 105, 19163–19184.

  • Pérez-Gussinyé, M. and Watts, A. B., The long-term strength of Europe and its implications for plate-forming processes. Nature, 2005, 436, 381–384.

  • Kirby, J. F. and Swain, C. J., A reassessment of spectral Te estimation in continental interiors: the case of North America. J. Geophys. Res.: Solid Earth, 2009, 114, B08401.

  • Pérez-Gussinyé, M., Lowry, A. R. and Watts, A. B., Effective elastic thickness of South America and its implications for intracontinental deformation. Geochem. Geophys. Geosyst., 2007, 8, Q05009.

  • Pérez-Gussinyé, M., Metois, M., Fernández, M., Vergés, J., Fullea, J. and Lowry, A. R., Effective elastic thickness of Africa and its relationship to other proxies for lithospheric structure and surface tectonics. Earth Planet. Sci. Lett., 2009, 287, 152–167.

  • Burov, E. B., Kogan, M. G., Lyon-Caen, H. and Molnar, P., Gravity anomalies, the deep structure, and dynamic processes beneath the Tien Shan. Earth Planet. Sci. Lett., 1990, 96, 367–383.

  • Burov, E. B. and Molnar, P., Gravity anomalies over the Ferghana Valley (Central Asia) and intracontinental deformation. J. Geophys. Res.: Solid Earth, 1998, 103, 18137–18152.

  • Haddad, D. and Watts, A. B., Subsidence history, gravity anomalies, and flexure of the northeast Australian margin in Papua New Guinea. Tectonics, 1999, 18, 827–842.

  • Burov, E. B., The equivalent elastic thickness (Te), seismicity and the long-term rheology of continental lithosphere: time to burn-out ‘crème brûlée’?. Insights from large-scale geodynamic modeling. Tectonophysics, 2010, 484, 4–26.

  • Stephenson, R., Flexural models of continental lithosphere based on the long‐term erosional decay of topography. Geophys. J. Int., 1984, 77, 385–413.

  • Zuber, M. T., Bechtel, T. D. and Forsyth, D. W., Effective elastic thicknesses of the lithosphere and mechanisms of isostatic compensation in Australia. J. Geophys. Res.: Solid Earth, 1989, 94, 9353–9367.

  • Grotzinger, J. and Royden, L., Elastic strength of the Slave craton at 1.9 Gyr and implications for the thermal evolution of the continents. Nature, 1990, 347, 64–66.

  • Armstrong, G. D. and Watts, A. B., Spatial variations in Te in the southern Appalachians, eastern United States. J. Geophys. Res.: Solid Earth, 2001, 106, 22009–22026.

  • Billen, M. I. and Gurnis, M., Constraints on subducting plate strength within the Kermadec trench. J. Geophys. Res.: Solid Earth, 2005, 110, B05407.

  • Pérez-Gussinyé, M., Lowry, A. R., Watts, A. B. and Velicogna, I., On the recovery of effective elastic thickness using spectral methods: examples from synthetic data and from the Fennoscandian Shield. J. Geophys. Res.: Solid Earth, 2004, 109, B10409.

  • Wieczorek, M. A. and Simons, F. J., Localized spectral analysis on the sphere. Geophys. J. Int., 2005, 162, 655–675.

  • McKenzie, D., The influence of dynamically supported topography on estimates of Te. Earth Planet. Sci. Lett., 2010, 295, 127–138.

  • Tesauro, M., Audet, P., Kaban, M. K. and Cloetingh, S., The effective elastic thickness of the continental lithosphere: comparison between rheological and inverse approaches. Geochem. Geophys. Geosystems., 2012, 13, Q09001.

  • McNutt, M. K., Influence of plate subduction on isostatic compensation in northern California. Tectonics, 1983, 2, 399–415.

  • Stark, C. P., Stewart, J. and Ebinger, C. J., Wavelet transform mapping of effective elastic thickness and plate loading: validation using synthetic data and application to the study of southern African tectonics. J. Geophys. Res.: Solid Earth, 2003, 108.

  • Simons, F. J. and Olhede, S. C., Maximum-likelihood estimation of lithospheric flexural rigidity, initial-loading fraction and load correlation, under isotropy. Geophys. J. Int., 2013, 193, 1300–1342.

  • Cochran, J. R., Some remarks on isostasy and the long-term behavior of the continental lithosphere. Earth Planet. Sci. Lett., 1980, 46, 266–274.

  • Maggi, A., Jackson, J. A., Priestley, K. and Baker, C., A re-assessment of focal depth distributions in southern Iran, the Tien Shan and northern India: do earthquakes really occur in the continental mantle? Geophys. J. Int., 2000, 143, 629–661.

  • Jackson, J., Strength of the continental lithosphere: time to abandon jelly sandwich? GSA Today, 2002, 12, 4–9.

  • Handy, M. R. and Brun, J. P., Seismicity, structure and strength of the continental lithosphere. Earth Planet. Sci. Lett., 2004, 223, 427–441.

  • McKenzie, D., Jackson, J. and Priestley, K., Thermal structure of oceanic and continental lithosphere. Earth Planet. Sci. Lett., 2005, 233, 337–349.

  • Kirby, J. F., Estimation of the effective elastic thickness of the lithosphere using inverse spectral methods: the state of the art. Tectono-physics, 2014, 631, 87–116.

  • Patriat, P. and Achache, J., India–Eurasia collision chronology has implications for crustal shortening and driving mechanism of plates. Nature, 1984, 311, 615–621.

  • Ni, J. and Barazangi, M., Seismotectonics of the Himalayan collision zone: geometry of the underthrusting Indian plate beneath the Himalaya. J. Geophys. Res.: Solid Earth, 1984, 89, 1147–1163.

  • Argand, E., La tectonique de l’Asie. Conférence faite á Bruxelles, le 10 août 1922. In Congrès géologique international (XIIIe session) – Belgique 1922 Belgium, 1922, pp. 171–372.

  • Owens, T. J. and Zandt, G., Implications of crustal property variations for models of Tibetan plateau evolution. Nature, 1997, 387, 37–43.

  • Willett, S. D. and Beaumont, C., Subduction of Asian lithospheric mantle beneath Tibet inferred from models of continental collision. Nature, 1994, 369, 642–645.

  • England, P. and Houseman, G., Finite strain calculations of continental deformation: 2. Comparison with the India–Asia collision zone. J. Geophys. Res.: Solid Earth, 1986, 91, 3664–3676.

  • Molnar, P., England, P. and Martinod, J., Mantle dynamics, uplift of the Tibetan Plateau, and the Indian monsoon. Rev. Geophys., 1993, 31, 357–396.

  • Royden, L. H. et al., Surface deformation and lower crustal flow in eastern Tibet. Science, 1997, 276, 788–790.

  • Royden, L. H., Burchfiel, B. C. and Hilst, R. D. van der, The geological evolution of the Tibetan plateau. Science, 2008, 321, 1054–1058.

  • Miyashiro, A. and Aki, K., Orogeny, John Wiley, Chichester, 1982, pp. 103–106.

  • Jin, Y., McNutt, M. K. and Zhu, Y. S., Mapping the descent of Indian and Eurasian plates beneath the Tibetan Plateau from gravity anomalies. J. Geophys. Res.: Solid Earth, 1996, 101, 11275–11290.

  • Van der Voo, R., Spakman, W. and Bijwaard, H., Tethyan subducted slabs under India. Earth Planet. Sci. Lett., 1999, 171, 7–20.

  • Kosarev, C., Kind, R., Sobolev, S. V., Yuan, X., Hanka, W. and Oreshin, S., Seismic evidence for a detached Indian lithospheric mantle beneath Tibet. Science, 1999, 283, 1306–1309.

  • Kind, R. et al., Seismic images of crust and upper mantle beneath Tibet: evidence for Eurasian plate subduction. Science, 2002, 298, 1219–1221.

  • Gansser, A., Geology of the Himalayas, Interscience, Zurich, 1964, pp. 251–279.

  • Powell, C. M. A. and Conaghan, P. J., Plate tectonics and the Himalayas. Earth Planet. Sci. Lett., 1973, 20, 1–12.

  • Zhao, W. et al., Deep seismic reflection evidence for continental underthrusting beneath southern Tibet. Nature, 1993, 366, 557–559.

  • Lyon-Caen, H. and Molnar, P., Constraints on the structure of the Himalaya from an analysis of gravity anomalies and a flexural model of the lithosphere. J. Geophys. Res., 1983, 88, 8171–8191.

  • Lyon-Caen, H. and Molnar, P., Gravity anomalies, flexure of the Indian plate, and the structure, support and evolution of the Himalaya and Ganga basin. Tectonics, 1985, 4, 513–538.

  • Royden, L., Coupling and decoupling of crust and mantle in convergent orogens: Implications for strain partitioning in the crust. J. Geophys. Res.: Solid Earth, 1996, 101, 17679–17705.

  • Karner, G. D. and Watts, A. B., Gravity anomalies and flexure of the lithosphere at mountain ranges. J. Geophys. Res.: Solid Earth, 1983, 88, 10449–10477.

  • Masek, J. G., Isacks, B. L., Fielding, E. J. and Browaeys, J., Rift flank uplift in Tibet: evidence for a viscous lower crust. Tectonics, 1994, 13, 659–667.

  • Ravikumar, M., Singh, B., Pavan Kumar, V., Satyakumar, A. V., Ramesh, D. S. and Tiwari, V. M., Lithospheric density structure and effective elastic thickness beneath Himalaya and Tibetan Plateau: inference from the integrated analysis of gravity, geoid, and topographic data incorporating seismic constraints. Tectonics, 2020, 39, e2020TC006219.

  • Tiwari, V. M. and Mishra, D. C., Estimation of effective elastic thickness from gravity and topography data under the Deccan Volcanic Province, India. Earth Planet. Sci. Lett., 1999, 171, 289–299.

  • Tiwari, V. M. and Mishra, D. C., Isostatic compensation of continental and oceanic topographies of Indian lithosphere. In Five Decades of Geophysics in India, Geological Society of India, 2008, pp. 173–190.

  • Rajesh, R. S., Stephen, J. and Mishra, D. C., Isostatic response and anisotropy of the Eastern Himalayan–Tibetan Plateau: a reappraisal using multitaper spectral analysis. Geophys. Res. Lett., 2003, 30, 1060.

  • Rajesh, R. S. and Mishra, D. C., Lithospheric thickness and mechanical strength of the Indian shield. Earth Planet. Sci. Lett., 2004, 225, 319–328.

  • Yadav, R. and Tiwari, V. M., Numerical simulation of present day tectonic stress across the Indian subcontinent. Int. J. Earth Sci., 2018, 107, 2449–2462.

  • Chen, B., Liu, J., Chen, C., Du, J. and Sun, Y., Elastic thickness of the Himalayan–Tibetan orogen estimated from the fan wavelet coherence method, and its implications for lithospheric structure. Earth Planet. Sci. Lett., 2015, 409, 1–14.

  • Hetényi, G. et al., Segmentation of the Himalayas as revealed by arc-parallel gravity anomalies. Sci. Rep., 2016, 6, 33866.

  • Tiwari, V. M., Vyghreswara Rao, M. B. S., Mishra, D. C. and Singh, B., Crustal structure across Sikkim, NE Himalaya from new gravity and magnetic data. Earth Planet. Sci. Lett., 2006, 247, 61–69.

  • Kaban, M. K., Chen, B., Tesauro, M., Petrunin, A. G., el Khrepy, S. and Al-Arifi, N., Reconsidering effective elastic thickness estimates by incorporating the effect of sediments: a case study for Europe. Geo-phys. Res. Lett., 2018, 45, 9523-9532.

  • Arjun, V. H., Gupta, S. and Tiwari, V. M., Lithospheric structure of the Dharwar Craton (India) from joint analysis of gravity, topography, and teleseismic travel-time residuals. J. Asian Earth Sci., 2022, 239, 105397.

  • Arjun, V. H., Continental lithospheric strength inferred from joint modelling of gravity, teleseismic travel time residuals and topography, Ph.D. thesis, Academy of Scientific and Innovative Research, Ghaziabad, 2023.


Abstract Views: 194

PDF Views: 96




  • Effective Elastic Thickness of the Continental Lithosphere with Particular Reference to the India–Eurasia Collision System

Abstract Views: 194  |  PDF Views: 96

Authors

V. H. Arjun
CSIR-National Geophysical Research Institute, Hyderabad 500 007, India
V. M. Tiwari
CSIR-National Geophysical Research Institute, Hyderabad 500 007, India
Sandeep Gupta
CSIR-National Geophysical Research Institute, Hyderabad 500 007, India

Abstract


The effective elastic thickness (EET) of the lithosphere is a measure of the lithosphere’s ability to flex under long-term geological and topographic loads. It is often estimated through analyses of gravity and topographic data. The EET has a significant role in regulating the geodynamic evolution of both the continental and oceanic plates. Estimates of EET derived from geophysical data are consistent with rheological models in the oceanic regions. However, there are extensive debates on the estimates of EET and rheological models over the continental areas; differences are probably due to the complex structure and history of the continental plates. For instance, according to one model of continental rheology, popularly known as the ‘Jelly Sandwich’, the mechanical strength of the lithospheric plate is distributed in the upper crust and the lithospheric mantle. In another model, dubbed as ‘Crème Brulee’, the lithospheric mantle is weak, and the mechanical strength of the lithosphere is limited to the upper portion of the crust. These model differences have arisen because of inconsistent results obtained using different datasets, e.g. the distribution of earthquakes, EET, gravity anomaly and rheology. This article discusses the evolution of these contrasting models and the critical necessity to resolve the model differences.

Keywords


Continental Rheology, Effective Elastic Thickness, Flexural Modelling, Isostasy, Lithosphere.

References





DOI: https://doi.org/10.18520/cs%2Fv125%2Fi7%2F748-757