Charles J. Ammon
Professor of Geosciences

Department of Geosciences
440 Deike Building
University Park, PA 16870

Voice: (814) 865-2310 / FAX: (814) 863-7823
charlesammon@psu.edu

My research is focused on the use of seismograms to better image earth structure and earthquake ruptures. My current research projects include the combination of receiver functions and surface-wave dispersion to improve estimates of lithospheric structure. The geographic focus of this work is Africa and Eurasia. Together with former graduate students Minoo Kosarian and Monica Maceira and current student Winchelle Sevilla I am analyzing observations from about 200 seismic stations spread across the region. Current Ph.D. student Vicki Miller has been working on seismicity and what it means with regard to the ongoing eruption of Soufrierre Hills Volcano on Montserrat. In addition, I am working with Sarah Barrett and Mike Cleveland (M. Sc. students) on interesting aspects of subduction zone earthquake processes. I am also developing methods to exploit seismic surface waves to improve earthquake locations in remote regions. Finally, I have ongoing work in tomographic imaging of earthquakes and earth structure with researchers from other institutions.

Ammon, C. J., T. Lay, and D. Simpson, Great Earthquakes and Global Seismic Networks, Seismol. Res. Letters, 81 (6) pp. 965-971, 2010.

Lay, T., C. J. Ammon, H. Kanamori, L. Rivera, K. Koper, A. Hutko, The 2009 Samoa-Tonga great earthquake triggered doublet, The 2009 Samoa-Tonga great earthquake triggered doublet, Nature 466, 964968, doi:10.1038/nature09214.

Lay, T., C. J. Ammon, H. Kanamori, K. D. Koper, O. Sufri, and A. R. Hutko, Teleseismic inversion for rupture process of the 27 February 2010 Chile (Mw 8.8) earthquake, Geophys. Res. Lett., 37, L13301, doi:10.1029/2010GL043379, 2010.

Lay, T., C. J. Ammon, H. Kanamori, K. Koper, O. Sufri, A. Hutko, Teleseismic inversion for rupture process of the 27 February 2010 Chile (Mw 8.8) earthquake, Geophys. Res. Letters, in press, 2010.

Miller, V., B. Voight, C. J. Ammon, E. Shalev, and G. Thompson, Seismic expression of magma-induced crustal strains and localized fluid pressures during initial eruptive stages, Soufriere Hills volcano, Montserrat, in press Geophys. Res. Letters, 2010.

Sevilla, W. I., C. J. Ammon, B. Voight, and S. De Angelis, Crustal structure beneath the Montserrat region of the Lesser Antilles island arc, Geochem. Geophys. Geosyst., 11, doi:10.1029/2010GC003048, in press, 2010

Lay, T., C. J. Ammon, A. R. Hutko, and H. Kanamori, Effects of Kinematic Constraints on Teleseismic Finite-Source Rupture Inversions: Great Peruvian Earthquakes of 23 June 2001 and 15 August 2007, Bull. Seismol. Soc. Am., 100, 969-994, doi:10.1785/0120090274, 2010.

Lay, T., H. Kanamori, C. J. Ammon, A. R. Hutko, K. Furlong, and L. Rivera, The 2006-2007 Kuril Islands great earthquake sequence, Journal of Geophysical Research, 114, 2009.

Maceira, M. and C. J. Ammon. Joint inversion of surface wave velocity and gravity observations and its application to central Asian basins shear velocity structure, J Geophys Res, 114, B02314, doi:10.1029/2007JB005157, 2009.

Furlong, K. P., T. Lay, and C.J. Ammon, A Great Earthquake Rupture Across a Rapidly Evolving Three-Plate Boundary, Science, 324, 226-229, doi:10.1126/science.1167476, 2009.

Hayes, G. P., K. P. Furlong, and C. J. Ammon, Intraplate deformation adjacent to the Macquarie Ridge south of New Zealand - The tectonic evolution of a complex plate boundary, Tectonophysics, 463, p. 1-14, 2009.

Ammon, C. J., H. Kanamori, and T. Lay, A great earthquake doublet and seismic stress transfer cycle in the central Kuril islands, Nature, 451, 561-565, 2008.

Ammon, C. J. and T. Lay, USArray Records the 9 October 2006 North Korean Nuclear Test, Eos, Trans. American Geophys. Union, 88, pages 37, 38, 2007.

Cho, K. H., R. B. Herrmann, C. J. Ammon and K. Lee (2006), Imaging the Upper Crust of the Korean Peninsula by Surface-Wave Tomography, Bull. Seism. Soc. Am., 97: 198 - 207, 2007.

Ammon, C. J., H. Kanamori, T. Lay, and A. A. Velasco (2006), The 17 July 2006 Java Tsunami Earthquake, Geophys. Res. Lett., 33, L24308, doi:10.1029/2006GL028005, 2006.

Velasco, A. A., C. J. Ammon, and T. Lay (2006), A search for seismic radiation from late slip for the December 26, 2004 Sumatra-Andaman (Mw = 9.15) earthquake, Geophys. Res. Lett., 33, L18305, doi:10.1029/2006GL027286.

Ketter, B. S., A. A. Velasco, C. J. Ammon, and G. E. Randall (2006), Path-specific velocity structure of western China from surface-wave dispersion, Pure and Appl. Geophys., 163, 1235-1255, doi:10.1007/s00024-006-0071-9.

Ammon, C. J., A. A. Velasco, and T. Lay (2006), Rapid estimation of first-order rupture characteristics for large earthquakes using surface waves: 2004 Sumatra-Andaman earthquake, Geophys. Res. Lett., 33, L14314, doi:10.1029/2006GL026303.

Ammon, C.J. (2006), Megathrust investigations (News and Views), Nature, 440 (7080), 31-32.

Maceira, M., S.R. Taylor, C.J. Ammon, X. Yang, and A.A. Velasco (2005), High Resolution Rayleigh Wave Slowness Tomography of Central Asia, J. Geophys. Res., 110, doi:10.1029/2004JB003429.

Julià, Jordi, C. J. Ammon,& A. A. Nyblade (2005), Evidence for mafic lower crust in Tanzania, East Africa, from joint inversion of receiver functions and Rayleigh wave dispersion velocities, Geophys. J. Int. 162, 555-569, doi: 10.1111/j.1365-246X.2005.02685.x.

Ammon, C. J., C. Ji, H.-K. Thio, D. Robinson, S. Ni, H. Kanamori, T. Lay, S. Das, D. Helmberger, V. Hjorleifsdottir, G. Ichinose, J. Polet, D. Wald (2005), Rupture Process of the 2004 Sumatra-Andaman Earthquake, Science, 308, 1133-1139.

Lay,T., H. Kanamori, C. J. Ammon, M. Nettles, R. Aster, S. L. Beck, S. Bilek, M. R. Brudzinski, R. Butler, H. R. DeShon, G. Ekström, K. Satake, S. Sipkin, S. N. Ward (2005), The Great Sumatra-Andaman Earthquake of 26, December 2004, Science, 308, 1127-1133.

Velasco, A. A., C. J. Ammon, J. Farrell, K. Pankow (2004), Rupture Directivity of the November 3, 2002 Denali Earthquake determined from surface waves, Bull. Seism. Soc. Am., 94, S293-S299.

Julià, J., C. J. Ammon, and R. B. Herrmann (2004), Lithospheric Structure of the Arabian Shield from the Joint Inversion of Receiver Functions and Surface Wave Dispersion, Tectonophysics, 371, 1-21.