Karin Sigloch

Karin Sigloch

Associate Professor of Geophysics
Tel: (+44) (0) 1865 272027

Research Profile

Seismology and Geodynamics. My group studies the structure of the earth’s interior, from crust to core. We want to understand its heat and material flows, which move slowly on a human timescale, but vigorously on geological time scales. These flows drive the motions of tectonic plates, formation of oceans, volcanism, and continental tectonics — surface observables that we link to 3-D images of mantle structure at depth.

Our primary tool is seismic tomography, an imaging technique that computes three-dimensional models of the earth’s interior. Essentially, it maps out the anomalously hot, cold, or dense regions that drive convection in the mantle. We specialize in cutting-edge methods for waveform inversion. PhD projects would typically advance the techniques of seismic tomography, and/or apply these tools to new, rapidly growing data sets.

http://rhum-rum.net/images/logo.png

We also do field experiments, including novel recordings on the ocean bottom. The RHUM-RUM experiment in the western Indian Ocean is a passive seismic experiment designed to image an oceanic mantle plume – or lack of plume – from crust to core beneath La Réunion Island, and to understand these results in terms of material, heat flow and plume dynamics. We deployed 57 broadband ocean-bottom seismometers and 30 island stations to record earthquakes and ambient noise between 2011 and 2014. The data analysis is ongoing and the growing list of publications can be found here on ResearchGate or by searching for “RHUM-RUM” in Google Scholar.

Farallon plate. 3-D computer model of a seismically active slab of the Earth's mantle under western North America known as the Farallon plate. The data for this image was obtained from hundreds of ground-based sensors that measure seismic activity. The data was processed by computer to create a 3-D model using a similar process to 3-D medical tomography. The upper translucent layer is the mountainous land, flanked to the left by the Pacific Ocean. Beneath it is the Farallon plate down to 1,500 kilometres depth. This former piece of ocean crust has been sinking for the past 150 million years. Colours represent 200 kilometre depth intervals.

The Farallon plate that subducts into the mantle beneath western North America, as imaged by 3-D seismic tomography down to 1,500 kilometres depth. This paleo-oceanic lithosphere once occupied the proto-Pacific basin but has been recycled back into the mantle over the past 180+ million years. Colours represent 200 kilometre depth intervals.

Linking our findings to neighbouring fields (plate reconstructions, field geology, geodynamic modelling) is the ultimate challenge and a source of great intellectual excitement. My ERC-funded project DEEPTIME matches deep slab structure to the geological surface record of subduction – volcanic arcs and other crustal slivers that stayed afloat, survived collisions, and form the world’s largest mountain belts. Integrating these two direct records of subduction, the project will:

  • Add paleo-trenches to existing plate reconstructions and extend them 2-3 times longer into the past.
  • Produce a 3-D atlas of the mantle that matches subducted seafloor with paleo-oceans inferred by land geology.
  • Rigorously test the hypothesis of vertical slab sinking, which may yield an absolute mantle reference frame.File:European Research Council logo.svg

https://www.leverhulme.ac.uk/sites/default/files/imported_images/440.jpg

Additional funding for this paleogeography work comes from the Levehulme Trust, via a Philip Levehulme Prize received in 2015.

Links

Publications: To download PDFs of most of my papers, scroll down to section “Selected Publications” or see here. Alternatively, browse and download on my ResearchGate pages, or view the list on Google Scholar.

DEEPTIME, my ERC grant: Deep Earth Evolution and Paleogeography Through Tomographic Imaging of the Mantle.

Seismology@Oxford research pages

NERC Doctoral Training Programme in Environmental Research

Earth Sciences at Exeter College, my college within the University of Oxford, where I am a Tutorial Fellow in Earth Sciences. (The second Earth Sciences fellow at Exeter is Conall MacNiocaill.)

 

Teaching Profile

Selected Publications

  • Sigloch, K. & Mihalynuk, M.G. (2017). Mantle and geological evidence for a Jura-Cretaceous suture spanning North America. Geological Society of America Bulletin, accepted subject to minor revision. PDF.
  • Stähler, S.C. & Sigloch, K. (2016). Fully probabilistic seismic source inversion – Part 2: Modelling errors and station covariances. Solid Earth, 7(6), pp.1521-1536. doi:10.5194/se-7-1521-2016. PDF (Open Access) / Supplement.
  • Scholz, J.R., Barruol, G., Fontaine, F.R., Sigloch, K., Crawford, W.C., Deen, M. (2017). Orienting ocean-bottom seismometers from P-wave and Rayleigh wave polarizations. J. Int., 208(3), 1277-1289. doi.org/10.1093/gji/ggw426. PDF.
  • Zhang, R., Czado, C. & Sigloch, K. (2016). Bayesian spatial modelling for high-dimensional seismic inverse problems, Journal of the Royal Statistical Society, Series C, doi:10.1111/rssc.12118. PDF / Supplement.
  • Hosseini. K. & Sigloch, K. (2015). Finite-frequency measurements of core-diffracted P-waves (Pdiff), Geophys. J. Int., 203(1), 506-521. PDF.
  • Stähler, S., Sigloch, K., Hosseini, K., Crawford, W.C., Barruol, G., Schmidt-Aursch, M.C., Tsekhmistrenko, M., Mazzullo, M. (2015). Preliminary performance report of the RHUM-RUM ocean-bottom seismometer network around La Réunion, western Indian Ocean. Advances in Geosciences 41, 34-63. doi:10.5194/adgeo-41-43-2016. PDF (Open Access) / Supplement.
  • Barruol, G., Davy, C., Fontaine F.R., Schlindwein, V., Sigloch, K. (2016). Monitoring austral and cyclonic swells in the Iles Eparses (Mozambique Channel) from microseismic noise, Acta Oecologica 72, 120-128. doi:10.1016/j.actao.2015.10.015. PDF.
  • Davy, C., Barruol, G., Fontaine, F.R., Sigloch, K., Stutzmann, E. (2014). Tracking major storms from microseismic and hydroacoustic observations on the seafloor, Geoph. Res. Letters, 41, doi:10.1002/2014GL062319. PDF / Supplement.
  • Stähler, S.C., Sigloch, K., 2013. Fully probabilistic seismic source inversion – Part 1: Efficient parameterisation, Solid Earth, 5, 1125-1162, doi:10.5194/sed-5-1125-2013. PDF / Supplement.
  • Forbriger, T., et al. (2014). Toolbox for Applied Seismic Tomography (TOAST), in Weber. M., Münch, U. (eds.), Tomography of the Earth’s Crust, Springer International monograph. PDF.
  • Sigloch, K. (2014). Cruise Report R/V METEOR, Cruise No. 101: METEOR-Berichte.
    RHUM-RUM – Seismological Imaging of a Mantle Plume under La Réunion, Western Indian Ocean – October 23 – December 4, 2013 – Port Louis (Mauritius) – Le Port (La Réunion, France)). Published by: DFG-Senatskommission für Ozeanographie , Bremen. DOI: 10.2312/cr_m101. PDF.
  • Sigloch, K., Mihalynuk, M.G., 2013. Intra-oceanic subduction shaped the assembly of Cordilleran North America. Nature 496, 50-56. PDF & Supplement.
  • Barruol, G., Sigloch, K., 2013. Investigating La Reunion hotspot from crust to core, Eos, Transactions American Geophysical Union, 94(23), 205-207, doi:10.1002/2013EO230002. PDF.
  • Zhang, R., Czado, C., Sigloch, K., 2013. A Bayesian linear model for the high-dimensional inverse problem of seismic tomography, Annals of Applied Statistics, 7(2), 1111-11138, doi:10.1214/12-AOAS623. PDF / Supplement.
  • Scheingraber, C., Hosseini, K., Barsch, R., & Sigloch, K. (2013). ObsPyLoad: A Tool for Fully Automated Retrieval of Seismological Waveform Data. Seismological Res. Lett. 84(3), 525-531. PDF / Supplement.
  • Charléty, J., Voronin, S., Nolet, G., Loris, I., Simons, F. J., Sigloch, K., & Daubechies, I. C. (2013). Global seismic tomography with sparsity constraints: Comparison with smoothing and damping regularization. Journal of Geophysical Research: Solid Earth, 118(9), 4887-4899. PDF.
  • Pavlis, G.L., Sigloch, K., Burdick, S., Fouch, M.J., Vernon, F.L., 2012. Unraveling the Geometry of the Farallon Plate: Synthesis of Three-Dimensional Imaging Results from USArray, Tectonophysics, doi:10.1016/j.tecto.2012.02.008. PDF.
  • Stähler, S.C., Sigloch, K., Nissen-Meyer, T., 2012. Triplicated P-wave measurements for waveform tomography of the mantle transition zone, Solid Earth, doi:10.5194/se-3-339-2012. PDF Open Access.
  • Sigloch, K., 2011. Mantle provinces under North America from multifrequency P wave tomography. Geochemistry, Geophysics, Geosystems 12. PDF.
  • Tian, Y., Zhou, Y., Sigloch, K., Nolet, G., & Laske, G. (2011). Structure of North American mantle constrained by simultaneous inversion of multiple‐frequency SH, SS, and Love waves. Journal of Geophysical Research: Solid Earth (1978–2012), 116(B2). PDF.
  • Tian, Y., Sigloch, K., Nolet, G., 2009. Multiple-frequency SH-wave tomography of the western US upper mantle. Geophysical Journal International 178, 1384-1402. PDF.
  • Sigloch, K., McQuarrie, N., Nolet, G., 2008. Two-stage subduction history under North America inferred from multiple-frequency tomography. Nature Geoscience 1, 458-462. PDF & Supplement.
  • Sigloch, K. (2008). Multiple-frequency body-wave tomography. PhD thesis, Princeton University. PDF.
  • Sigloch, K., Nolet, G., 2006. Measuring finite-frequency body wave amplitudes and traveltimes, Geophysical Journal International, 167(1), 271-287, doi:10.1111/j.1365-246X.2006.03116.x. PDF / Supplement.
  • Sigloch, K., Andrews, M. R., Mitra, P. P., & Thomson, D. J. (2005). Communicating over nonstationary nonflat wireless channels. IEEE Transactions on Signal Processing, 53(6), 2216-2227. PDF.