Annemarie Baltay

Full name: Annemarie Baltay Sundstrom


I study how physical measures of earthquakes and the earth control ground motions measured at distance, and how ground motion observations can be used to gain insight on the earthquake source and path. I am particularly interested in earthquake stress drop: how it is measured, what is the variability, and how that all relates to ground motion data and models. I am also focused on physical components and uncertainty of ground-motion prediction equations (GMPEs), a critical building block in hazard maps. Reducing the variability and uncertainty in GMPEs is imperative to building better hazard maps, as well as for performing more accurate site-specific hazard studies for critical facilities. Currently, I am working towards physical explanations for variability in the source, site, and path components in ground motions. Ultimately we will develop models for predicting those effects from geophysical observables, such as stress drop (for source), site velocity profiles and attenuation (for site), and whole-path attenuation (for path).


2011                       Ph.D. Geophysics, Department of Geophysics, Stanford University

2008                       M.S. Geophysics, Department of Geophysics, Stanford University

2005                       B.A. Applied Mathematics, Yale University


2013 - 2015            Mendenhall Postdoctoral Scholar, U.S. Geological Survey, Menlo Park

2012                       Postdoctoral Scholar, Department of Geophysics, Stanford University

2012                       Instructor, Understanding Natural Hazards, Quantifying Risk and Increasing Resilience in

                                            Highly Urbanized Regions, Department of Geology, Stanford University

2010                       Summer Intern for Europe Earthquake Model Development, Risk Management Solutions, Newark, CA

2009                       Graduate Student Researcher through NSF EAPSI, Department of Earth and Planetary Sciences, University of Tokyo

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Baltay, A. S., T. C. Hanks and N. A. Abrahamson, Uncertainty, variability and earthquake physics in Ground-Motion Prediction Equations, Bull. Seis. Soc. Am., 107(4), 10.1785/0120140023 10.1785/0120160164 [Link] 

Baltay, A. S. and J. Boatwright (2015), Ground-motion observations of the 2014 South Napa Earthquake, Seism. Res. Lett., 86(2A), doi: 10.1785/0220140232 [Link]

Brocher, T.M., Baltay, A. S., Hardebeck, J. L., Pollitz, F. F., Murray, J. R., Llenos, A. L., Schwartz, D. P., Blair, J. L., Ponti, D. J., Lienkaemper, J. J., Langenheim, V. E., Dawson, T. E., Hudnut, K. W., Shelly, D. R., Dreger, D., Boatwright, J., Aagaard, B. T., Wald, D. J., Allen, R. M., Barnhart, W. D., Knudsen, K. L., Brooks, B. A., and Scharer, K. M. (2015), The M6.0 24 August 2014 South Napa Earthquake, Seism. Res. Lett., 86(2A), doi: 10.1785/0220150004.

Baltay, A. S. and T. C. Hanks (2014), Understanding the magnitude dependence of PGA and PGV in NGA-West2 Data, Bull. Seis. Soc. Am.,104(6), doi: 10.1785/0120130283 [Link]

Bozorgnia, Y., N. A. Abrahamson, L. Al Atik, T. D. Ancheta, G. A. Atkinson, J. W. Baker, A. S. Baltay, et al., (2014), NGA-West2 Research Project, Earthquake Spectra, doi: [Link]

Yabe, S., A. S. Baltay, S. Ide and G. C. Beroza, (2014) Seismic-wave attenuation determined from tectonic tremor in multiple subduction zones, Bull. Seis. Soc. Am., 104(4), doi:10.1785/0120140023 [Link]

Baltay, A. S., G. C. Beroza and S. Ide (2014), Radiated energy of great earthquakes from teleseismic empirical Green’s function deconvolution, Pure Appl. Geophs., doi:10.1007/s00024-014-0804-0 [Link]

Baltay, A. S., T. C. Hanks and G. C. Beroza (2013) Stable Stress Drop Measurements and their Variability: Implications for Ground-Motion Prediction, Bull. Seism. Soc. Am.103(1), doi: 10.1785/0120120161. [Link]

Baltay, A. S. and G. C. Beroza (2013), Ground motion prediction from tremor, Geophys. Res. Lett, doi:10.1029/2013GL058506 [Link]

Ide, S., A. Baltay and G. C. Beroza, (2011) Shallow Dynamic Overshoot and Energetic Deep Rupture of the 2011 Mw 9.0 Tohoku-Oki Earthquake, Science 332, 6036, pp 1426 - 1429, doi:10.1126/science.1207020. [Link]

Baltay, A., S. Ide, G. Prieto, and G. C. Beroza, (2011) Variability in Earthquake Stress Drop and Apparent Stress, Geophys. Res. Lett. 38, L06303, doi:10.1029/2011GL046698 [Link]

Baltay, A., G. Prieto, and G. C. Beroza, (2010) Radiated seismic energy from coda measurements indicates no scaling in apparent stress with seismic moment, J. Geophys. Res. 115(B8), 1-12, doi:10.1029/2009JB006736 [Link]