Skip to main content Accessibility help
×
Hostname: page-component-586b7cd67f-t8hqh Total loading time: 0 Render date: 2024-11-22T14:44:56.670Z Has data issue: false hasContentIssue false

16 - Joint and Constrained Inversion as Hypothesis Testing Tools

from Part III - ‘Solid’ Earth Applications: From the Surface to the Core

Published online by Cambridge University Press:  20 June 2023

Alik Ismail-Zadeh
Affiliation:
Karlsruhe Institute of Technology, Germany
Fabio Castelli
Affiliation:
Università degli Studi, Florence
Dylan Jones
Affiliation:
University of Toronto
Sabrina Sanchez
Affiliation:
Max Planck Institute for Solar System Research, Germany
Get access

Summary

Abstract: In this chapter, I discuss an alternative perspective on interpreting the results of joint and constrained inversions of geophysical data. Typically such inversions are performed based on inductive reasoning (i.e. we fit a limited set of observations and conclude that the resulting model is representative of the Earth). While this has seen many successes, it is less useful when, for example, the specified relationship between different physical parameters is violated in parts of the inversion domain. I argue that in these cases a hypothesis testing perspective can help to learn more about the properties of the Earth. I present joint and constrained inversion examples that show how we can use violations of the assumptions specified in the inversion to study the subsurface. In particular I focus on the combination of gravity and magnetic data with seismic constraints in the western United States. There I see that high velocity structures in the crust are associated with relatively low density anomalies, a possible indication of the presence of melt in a strong rock matrix. The concepts, however, can be applied to other types of data and other regions and offer an extra dimension of analysis to interpret the results of geophysical inversion algorithms.

Type
Chapter
Information
Publisher: Cambridge University Press
Print publication year: 2023

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Afonso, J. C., Moorkamp, M., and Fullea, J. (2016). Imaging the lithosphere and upper mantle: Where we are at and where we are go. In Moorkamp, M., Lelièvre, P. G., Linde, N., and Khan, A. (eds.) Integrated Imaging of the Earth: Theory and Applications, AGU Geophysical Monograph 218. Hoboken, NJ: John Wiley & Sons, pp. 191218.Google Scholar
Afonso, J. C., Salajegheh, F., Szwillus, W., Ebbing, J., and Gaina, C. (2019). A global reference model of the lithosphere and upper mantle from joint inversion and analysis of multiple data sets. Geophysical Journal International, 217(3), 1602–28.Google Scholar
Astic, T., and Oldenburg, D. W. (2019). A framework for petrophysically and geologically guided geophysical inversion using a dynamic Gaussian mixture model prior. Geophysical Journal International, 219(3), 19892012.Google Scholar
Astic, T., Heagy, L. J., and Oldenburg, D. W. (2021). Petrophysically and geologically guided multi-physics inversion using a dynamic Gaussian mixture model. Geophysical Journal International, 224(1), 4068.CrossRefGoogle Scholar
Bankey, V., Cuevas, A., Daniels, D. et al. (2002). Digital data grids for the magnetic anomaly map of North America. USGS Open-File Report 02-414. https://pubs.usgs.gov/of/2002/ofr-02-414/.Google Scholar
Barton, P. J. (1986). The relationship between seismic velocity and density in the continental crust: A useful constraint? Geophysical Journal International, 87(1), 195208.CrossRefGoogle Scholar
Bedrosian, P. A., and Feucht, D. W. (2014). Structure and tectonics of the northwestern United States from EarthScope USArray magnetotelluric data. Earth and Planetary Science Letters, 402, 275–89.Google Scholar
Bennington, N. L., Zhang, H., Thurber, C. H., and Bedrosian, P. A. (2015). Joint inversion of seismic and magnetotelluric data in the Parkfield region of California using the normalized cross-gradient constraint. Pure and Applied Geophysics, 172(5), 1033–52.Google Scholar
Birch, F. (1961). The velocity of compressional waves in rocks to 10 kilobars: Part 2. Journal of Geophysical Research, 66(7), 2199–224.CrossRefGoogle Scholar
Blom, N., Boehm, C., and Fichtner, A. (2017). Synthetic inversions for density using seismic and gravity data. Geophysical Journal International, 209(2), 1204–20.CrossRefGoogle Scholar
Bosch, M. (2016). Inference networks in Earth models with multiple components and data. In Moorkamp, M., Lelièvre, P. G., Linde, N., and Khan, A. (eds.) Integrated Imaging of the Earth: Theory and Applications, AGU Geophysical Monograph 218. Hoboken, NJ: John Wiley & Sons, pp. 2947.CrossRefGoogle Scholar
Bosch, M., and McGaughey, J. (2001). Joint inversion of gravity and magnetic data under lithologic constraints. The Leading Edge, 20(8), 877–81.CrossRefGoogle Scholar
Bouligand, C., Glen, J. M. G., and Blakely, R. J. (2009). Mapping Curie temperature depth in the western United States with a fractal model for crustal magnetization. Journal of Geophysical Research: Solid Earth, 114(B11).Google Scholar
Bouligand, C., Glen, J. M. G., and Blakely, R. J. (2014). Distribution of buried hydrothermal alteration deduced from high-resolution magnetic surveys in Yellowstone National Park. Journal of Geophysical Research: Solid Earth, 119(4), 2595–630.Google Scholar
Carter-McAuslan, A., Leliévre, P. G. and Farquharson, C. G. (2015). A study of fuzzy c-means coupling for joint inversion, using seismic tomography and gravity data test scenarios. GEOPHYSICS, 80(1), W1W15.Google Scholar
Chen, C. W., Rondenay, S., Weeraratne, D. S., and Snyder, D. B. (2007).New constraints on the upper mantle structure of the Slave Craton from Rayleigh wave inversion. Geophysical Research Letters, 34, L10301. https://doi.org/10.1029/2007GL029535Google Scholar
Chulliat, A., Brown, W., Alken, P. et al. (2020). The US/UK world magnetic model for 2020–2025: Technical Report. National Centers for Environmental Information (U.S.); British Geological Survey. https://doi.org/10.25923/ytk1-yx35CrossRefGoogle Scholar
Colombo, D., and Rovetta, D. (2018). Coupling strategies in multiparameter geophysical joint inversion. Geophysical Journal International, 215(2), 1171–84.Google Scholar
Darijani, M., Farquharson, C. G., and Lelièvre, P. G. (2021). Joint and constrained inversion of magnetic and gravity data: A case history from the McArthur River area, Canada. Geophysics, 86(2), B79B95.Google Scholar
de Groot-Hedlin, C., Constable, S., and Weitemeyer, K. (2003–4).Transfer functions for deep magnetotelluric sounding along the Yellowstone-Snake River hotspot track. https://doi.org/10.17611/DP/EMTF/YSRP/2004.CrossRefGoogle Scholar
Elsasser, W. M. (1950). The Earth’s interior and geomagnetism. Reviews of Modern Physics, 22(1), 135.CrossRefGoogle Scholar
Finn, C. A., and Morgan, L. A. (2002). High-resolution aeromagnetic mapping of volcanic terrain, Yellowstone National Park. Journal of Volcanology and Geothermal Research, 115(1-2), 207–31.CrossRefGoogle Scholar
Fishwick, S. (2010). Surface wave tomography: Imaging of the lithosphere-asthenosphere boundary beneath central and southern Africa? Lithos, 120(1–2), 6373.CrossRefGoogle Scholar
Franz, G., Moorkamp, M., Jegen, M., Berndt, C., and Rabbel, W. (2021). Comparison of different coupling methods for joint inversion of geophysical data: A case study for the Namibian continental margin. Journal of Geophysical Research: Solid Earth, 126 (12), e2021JB022092.Google Scholar
Fullagar, P. K., and Oldenburg, D. W. (1984). Inversion of horizontal loop electromagnetic frequency soundings. Geophysics, 49(2), 150–64.CrossRefGoogle Scholar
Gallardo, L. A., and Meju, M. A. (2003). Characterization of heterogeneous near-surface materials by joint 2D inversion of dc resistivity and seismic data. Geophysical Research Letters, 30(13), 1658.CrossRefGoogle Scholar
Gallardo, L. A., and Meju, M. A. (2007). Joint two-dimensional cross-gradient imaging of magnetotelluric and seismic traveltime data for structural and lithological classification. Geophysical Journal International, 169, 1261–72.Google Scholar
Gallardo, L. A., and Meju, M. A. (2011). Structure-coupled multiphysics imaging in geophysical sciences. Reviews of Geophysics, 49(1).CrossRefGoogle Scholar
Gao, H., and Shen, Y. (2014). Upper mantle structure of the Cascades from full-wave ambient noise tomography: Evidence for 3D mantle upwelling in the back-arc. Earth and Planetary Science Letters, 390, 222–33.CrossRefGoogle Scholar
Gardner, G. H. F., Gardner, L. W., and Gregory, A. R. (1974). Formation velocity and density: The diagnostic basics for stratigraphic traps. Geophysics, 39(6), 770–80.CrossRefGoogle Scholar
Ghalenoei, E., Dettmer, J., Ali, M. Y., and Kim, J. W. (2021). Gravity and magnetic joint inversion for basement and salt structures with the reversible-jump algorithm. Geophysical Journal International, 227(2), 746–58.CrossRefGoogle Scholar
Giraud, J., Pakyuz-Charrier, E., Jessell, M. et al. (2017). Uncertainty reduction through geologically conditioned petrophysical constraints in joint inversion. Geophysics, 82(6), ID19–ID34.CrossRefGoogle Scholar
Gross, L. (2019). Weighted cross-gradient function for joint inversion with the application to regional 3-D gravity and magnetic anomalies. Geophysical Journal International, 217(3), 2035–46.CrossRefGoogle Scholar
Haber, E., and Holtzman Gazit, M. (2013). Model fusion and joint inversion. Surveys in Geophysics, 34(5), 675–95.Google Scholar
Haber, E., and Oldenburg, D. W. (1997). Joint inversion: A structural approach. Inverse Problems, 13(1), 6377.Google Scholar
Harmon, N., Wang, S., Rychert, C. A. Constable, S., and Kendall, J. M. (2021). Shear velocity inversion guided by resistivity structure from the pi-lab experiment for integrated estimates of partial melt in the mantle. Journal of Geophysical Research: Solid Earth, e2021JB022202.Google Scholar
Heincke, B., Jegen, M., Moorkamp, M., Hobbs, R. W., and Chen, J. (2017). An adaptive coupling strategy for joint inversions that use petrophysical information as constraints. Journal of Applied Geophysics, 136, 279–97.Google Scholar
Hinze, W. J., Von Frese, R. R. B., and Saad, A. H. (2013). Gravity and magnetic exploration: Principles, practices, and applications. Cambridge: Cambridge University Press.Google Scholar
Hong, T., and Sen, M. K. (2009). A new MCMC algorithm for seismic waveform inversion and corresponding uncertainty analysis. Geophysical Journal International, 177 (1), 1432.CrossRefGoogle Scholar
IRIS. USArray Transportable Array. (2003). https://doi.org/10.7914/SN/TA.CrossRefGoogle Scholar
Julia, J., Ammon, C. J., Herrmann, R. B,. and Correig, A. M. (2000). Joint inversion of receiver function and surface wave dispersion observations. Geophysical Journal International,143(1), 99112.Google Scholar
Kamm, J., Lundin, I. A., Bastani, M., Sadeghi, M., and Pedersen, L. B. (2015). Joint inversion of gravity, magnetic, and petrophysical data: A case study from a gabbro intrusion in Boden, Sweden. Geophysics, 80(5), B131B152.Google Scholar
Kelbert, A., Egbert, G. D., and Schultz, A. (2011). IRIS DMC data services products: EMTF, the magnetotelluric transfer functions. https://doi.org/10.17611/DP/EMTF.1.CrossRefGoogle Scholar
Kelbert, A., Egbert, G. D., and deGroot-Hedlin, C. (2012). Crust and upper mantle electrical conductivity beneath the Yellowstone Hotspot Track. Geology, 40(5), 447–50.Google Scholar
Konstantinou, A., Strickland, A., Miller, E. L., and Wooden, J. P. (2012). Multistage Cenozoic extension of the Albion–Raft River–Grouse Creek metamorphic core complex: Geochronologic and stratigraphic constraints. Geosphere, 8(6), 1429–66.Google Scholar
Lelièvre, P. G., Bijani, R., and Farquharson, C. G. (2016). Joint inversion using multi-objective global optimization methods. In 78th EAGE Conference and Exhibition 2016. Houten: European Association of Geoscientists & Engineers. https://doi.org/10.3997/2214-4609.201601655.Google Scholar
Li, X., and Sun, J. (2022). Towards a better understanding of the recoverability of physical property relationships from geophysical inversions of multiple potential-field data sets.Geophysical Journal International, 230(3), 1489–507.Google Scholar
Linde, N., Binley, A., Tryggvason, A., Pedersen, L. B., and Revil, A. (2006). Improved hydrogeophysical characterization using joint inversion of cross-hole electrical resistance and ground-penetrating radar traveltime data. Water Resources Research, 42: 12404.Google Scholar
Linde, N., and Doetsch, J. (2016). Joint Inversion in Hydrogeophysics and Near-Surface Geophysics. In Moorkamp, M., Lelièvre, P. G., Linde, N., and Khan, A., eds., Integrated Imaging of the Earth: Theory and Applications. Hoboken, NJ: John Wiley & Sons, pp. 117–35.Google Scholar
Lines, L. R., Schultz, A. K., and Treitel, S. (1986). Cooperative inversion of geophysical data. Geophysics, 53(1), 820.Google Scholar
Liu, L., and Gao, S. S. (2018). Lithospheric layering beneath the contiguous United States constrained by S-to-P receiver functions. Earth and Planetary Science Letters, 495, 7986.Google Scholar
Maceira, M., and Ammon, C. J. (2009). Joint inversion of surface wave velocity and gravity observations and its application to central Asian basins shear velocity structure. Journal of Geophysical Research: Solid Earth, 114(B2), B02314.CrossRefGoogle Scholar
Mackie, R. L., Meju, M. A., Miorelli, F. et al. (2020). Seismic image-guided 3D inversion of marine controlled-source electromagnetic and magnetotelluric data. Interpretation, 8(4), SS1–SS13.Google Scholar
Manassero, M. C., Afonso, J. C., Zyserman, F I. et al. (2021). A reduced order approach for probabilistic inversions of 3D magnetotelluric data II: Joint inversion of MT and surface-wave data. Journal of Geophysical Research: Solid Earth, 126 (12), e2021JB021962.Google Scholar
Mandolesi, E., and Jones, A. G. (2014). Magnetotelluric inversion based on mutual information. Geophysical Journal International, 199(1), 242–52.Google Scholar
Martin, R., Giraud, J., Ogarko, V. et al. (2021). Three-dimensional gravity anomaly data inversion in the Pyrenees using compressional seismic velocity model as structural similarity constraints. Geophysical Journal International, 225(2), 1063–85.Google Scholar
Meilă, M. (2003). Comparing clusterings by the variation of information. In Schölkopf, B. and Warmuth, M. K., eds., Learning Theory and Kernel Machines: Lecture Notes in Computer Science, vol. 2777. Berlin: Springer, pp. 173–87. https://doi.org/10.1007/978-3-540-45167-9_14.Google Scholar
Meju, M., and Gallardo, L. A. (2016). Structural Coupling Approaches in Integrated Geophysical Imaging. In Moorkamp, M., Lelièvre, P. G., Linde, N., and Khan, A., eds., Integrated Imaging of the Earth: Theory and Applications. Hoboken, NJ: . John Wiley & Sons, pp. 4967.Google Scholar
Meju, M., Saleh, A. S., Mackie, R. L. et al. (2018). Workflow for improvement of 3D anisotropic CSEM resistivity inversion and integration with seismic using cross-gradient constraint to reduce exploration risk in a complex fold-thrust belt in offshore northwest Borneo. Interpretation, 6(3), SG49–SG57.Google Scholar
Meqbel, N. M., Egbert, G. D., Wannamaker, P. E., Kelbert, A., and Schultz, A. (2014). Deep electrical resistivity structure of the northwestern US derived from 3-D inversion of USArray magnetotelluric data. Earth and Planetary Science Letters, 402,290304.Google Scholar
Moorkamp, M. (2007). Joint inversion of MT and receiver-function data. PhD thesis, National University of Ireland, Galway.Google Scholar
Moorkamp, M. (2017). Integrating electromagnetic data with other geophysical observations for enhanced imaging of the Earth: A tutorial and review. Surveys in Geophysics, 38(5), 935–62.Google Scholar
Moorkamp, M. (2021). Joint inversion of gravity and magnetotelluric data from the Ernest Henry IOCG deposit with a variation of information constraint. In Swinford, B. and Abubakar, A. First International Meeting for Applied Geoscience & Energy. Houston, TX: Society of Exploration Geophysicists, pp. 1711–15.Google Scholar
Moorkamp, M. (2022). Deciphering the state of the lower crust and upper mantle with multi-physics inversion. Geophysical Research Letters, 49 (9), e2021GL096336.Google Scholar
Moorkamp, M., Jones, A. G., and Eaton, D. W. (2007). Joint inversion of teleseismic receiver functions and magnetotelluric data using a genetic algorithm: Are seismic velocities and electrical conductivities compatible? Geophysical Research Letters, 34(16), L16311.Google Scholar
Moorkamp, M., Roberts, A. W., Jegen, M., Heincke, B., and Hobbs, R. W. (2013). Verification of velocity-resistivity relationships derived from structural joint inversion with borehole data. Geophysical Research Letters, 40(14), 3596–601.Google Scholar
Moorkamp, M., Heincke, B., Jegen, M., Roberts, A. W., and Hobbs, R. W. (2011). A framework for 3-D joint inversion of MT, gravity and seismic refraction data. Geophysical Journal International, 184, 477–93.Google Scholar
Moorkamp, M., Heincke, B., Jegen, M., Roberts, A. W., and Hobbs, R. W. (2016a). Joint Inversion in Hydrocarbon Exploration. In Moorkamp, M., Lelièvre, P. G., Linde, N., and Khan, A., eds., Integrated Imaging of the Earth: Theory and Applications. Hoboken, NJ: John Wiley & Sons, pp. 167189.Google Scholar
Moorkamp, M., Lelièvre, P. G., Linde, N., and Khan, A., eds. (2016b). Integrated Imaging of the Earth. Hoboken, NJ: John Wiley & Sons.Google Scholar
Nafe, J. E., and Drake, C. L. (1957). Variation with depth in shallow and deep water marine sediments of porosity, density and the velocities of compressional and shear waves. Geophysics, 22(3), 523–52.Google Scholar
O’Donnell, J. P., Daly, E., Tiberi, C. et al. (2011). Lithosphere-asthenosphere interaction beneath Ireland from joint inversion of teleseismic p-wave delay times and grace gravity. Geophysical Journal International, 184(3), 1379–96.Google Scholar
Pail, R., Fecher, T., Barnes, D. et al. (2018). Short note: The experimental geopotential model XGM2016. Journal of Geodesy, 92(4), 443–51.Google Scholar
Panzner, M., Morten, J. P., Weibull, W. W., and Arntsen, B. (2016). Integrated seismic and electromagnetic model building applied to improve subbasalt depth imaging in the Faroe-Shetland basin. Geophysics, 81(1), E57E68.Google Scholar
Pasquale, V. (2011). Curie temperature. In Gupta, H. K., ed., Encyclopedia of Solid Earth Geophysics. Dordrecht: Springer, pp. 8990. https://doi.org/10.1007/978-90-481-8702-7_109.CrossRefGoogle Scholar
Paulatto, M., Moorkamp, M., Hautmann, S. et al. (2019). Vertically extensive magma reservoir revealed from joint inversion and quantitative interpretation of seismic and gravity data. Journal of Geophysical Research: Solid Earth, 124(11), 11170–91.Google Scholar
Pluim, J. P. W. Maintz, J. B. A. and Viergever, M. A. (2003). Mutual-information-based registration of medical images: A survey. IEEE Transactions on Medical Imaging, 22(8), 9861004.Google Scholar
Schmandt, B., and Humphreys, E. (2011). Seismically imaged relict slab from the 55 Ma Siletzia accretion to the northwest United States. Geology, 39(2), 175–8.Google Scholar
Schultz, A., Egbert, G. D., Kelbert, A. et al., and staff of the National Geoelectromagnetic Facility and their contractors. (2006–8). USArray TA magnetotelluric transfer functions. https://doi.org/10.17611/DP/EMTF/USARRAY/TA.Google Scholar
Shi, Z., Hobbs, R. W., Moorkamp, M., Tian, G., and Jiang, L. (2017). 3-D cross-gradient joint inversion of seismic refraction and dc resistivity data. Journal of Applied Geophysics, 141, 5467.Google Scholar
Spichak, V. V. (2020). Modern methods for joint analysis and inversion of geophysical data. Russian Geology and Geophysics, 61(3), 341–57.Google Scholar
Sun, J., and Li, Y. (2015a). Advancing the understanding of petrophysical data through joint clustering inversion: A sulfide deposit example from Bathurst mining camp. In Schneider, R. V., ed., SEG Technical Program Expanded Abstracts 2015. Houston, TX: Society of Exploration Geophysicists, pp. 2017–21.Google Scholar
Sun, J., and Li, Y. (2015b). Multidomain petrophysically constrained inversion and geology differentiation using guided fuzzy c-means clustering. Geophysics, 80(4), ID1–ID18.Google Scholar
Sun, J., and Li, Y. (2016). Joint inversion of multiple geophysical data using guided fuzzy c-means clustering. Geophysics, 81(3), ID37–ID57.Google Scholar
Sun, J., Melo, A. T., Kim, J. D., and Wei, X. (2017). Unveiling the 3D undercover structure of a Precambrian intrusive complex by integrating airborne magnetic and gravity gradient data into 3D quasi-geology model building. Interpretation, 8(4), SS15–SS29.Google Scholar
Tauxe, L., Luskin, C., Selkin, P., Gans, P., and Calvert, A. (2004). Paleomagnetic results from the Snake River Plain: Contribution to the time-averaged field global database. Geochemistry, Geophysics, Geosystems, 5(8), Q08H13. https://doi.org/10.1029/2003GC000661.Google Scholar
Tiberi, C., Diament, M., Déverchère, J. et al. (2003). Deep structure of the Baikal rift zone revealed by joint inversion of gravity and seismology. Journal of Geophysical Research: Solid Earth, 108(B3), 2133. https://doi.org/10.1029/2002JB001880.Google Scholar
Tu, X., and Zhdanov, M. S. (2021). Joint Gramian inversion of geophysical data with different resolution capabilities: Case study in Yellowstone. Geophysical Journal International, 226(2), 1058–85.Google Scholar
Wagner, F. M., Mollaret, C., Günther, T., Kemna, A., and Hauck, C. (2019). Quantitative imaging of water, ice and air in permafrost systems through petrophysical joint inversion of seismic refraction and electrical resistivity data. Geophysical Journal International 219(3), 1866–75.Google Scholar
Weise, B. (2021). Joint Inversion of magnetotelluric, seismic and gravity data. PhD thesis, University of Leicester.Google Scholar
Zhao, Y., Guo, L., Guo, Z. et al. (2020). High resolution crustal model of SE Tibet from joint inversion of seismic p-wave travel times and Bouguer gravity anomalies and its implication for the crustal channel flow. Tectonophysics, 792, 228580.Google Scholar
Zhdanov, M. S., Gribenko, A., and Wilson, G. (2012). Generalized joint inversion of multimodal geophysical data using Gramian constraints. Geophysical Research Letters, 39(9).Google Scholar
Zhou, J. Revil, A. Karaoulis, M. et al. (2014). Image-guided inversion of electrical resistivity data. Geophysical Journal International, 197 (1), 292309.Google Scholar
Zingerle, P., Pail, R., Gruber, T., and Oikonomidou, X. (2020). The combined global gravity field model xgm2019e. Journal of Geodesy, 94(7), 112.Google Scholar

Save book to Kindle

To save this book to your Kindle, first ensure [email protected] is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about saving to your Kindle.

Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.

Find out more about the Kindle Personal Document Service.

Available formats
×

Save book to Dropbox

To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Dropbox.

Available formats
×

Save book to Google Drive

To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Google Drive.

Available formats
×