Yan Zhan


  • M.S. Structure Geology, Peking University, China
  • B.S. Geochemsitry, Peking University, China

I'm a fourth year Ph.D. student of geophysics, working with Prof. P. M. Gregg. My current research focuses on modeling the mechanical evolution of active volcanic systems using model-data fusion techniques. My primary goal is to investigate the physical processes during a volcanic unrest. I am linking multidisciplinary volcanic unrest observations (e.g., surface deformation, seismicity, and gas emissions) to eruption potential by developing a model-data fusion framework based on the Ensemble Kalman Filter (EnKF). The EnKF provides updates of the model states of our target volcano whenever new observations are acquired (Gregg and Pettijohn, 2016; Zhan and Gregg, 2017Zhan et al., 2017). My another goal is to develop an open source data assimilation workflow for those institutes and organizations which cannot afford the commercial software. Therefore, we are currently developing our EnKF module based on Python and trying to find an alternative open source finite element code to simulate volcanic activities.



  1. Zhan, Y., Gregg, P.M., Le Mével, H., Miller, C.A., Cardona, C., Integrating reservoir dynamics, crustal stress, and geophysical observations of the Laguna del Maule magmatic system by FEM models and data assimilation. In prepare.
  2. Gregg, P.M., Zhan, Y., Amelung, F., Geist, D., Mothes, P., Koric, S., Yunjun, Z., Forecasting the June 26, 2018 Eruption of Sierra Negra Volcano, Gal√°pagos – Ecuador.


  1. Zhan, Y., Gregg, P.M., 2019. How accurately can we model magma reservoir failure with uncertainties in host-rock rheology? JGR solid earth. https://doi.org/10.1029/2019JB018178.
  2. Gregg, P.M., Lé Mevel, H., Zhan, Y., Dufek, J., Geist, D., Chadwick, W. W., 2018. Stress Triggering of the 2005 eruption of Sierra Negra volcano, Galápagos, Geophysical Research Letters, doi: 10.1029/2018GL080393.
  3. Zhan, Y., Gregg, P.M., Chaussard, E., Aoki, Y., 2017. Sequential Assimilation of Volcanic Monitoring Data to Quantify Eruption Potential: Application to Kerinci Volcano, Sumatra. Front. Earth Sci. 5. https://doi.org/10.3389/feart.2017.00108
  4. Zhan, Y., Gregg, P.M., 2017. Data assimilation strategies for volcano geodesy. Journal of Volcanology and Geothermal Research. doi:10.1016/j.jvolgeores.2017.02.015.
  5. Zhan, Y., Hou, G., Kusky, T., Gregg, P.M., 2016. Stress development in heterogenetic lithosphere: Insights into earthquake processes in the New Madrid Seismic Zone. Tectonophysics 671, 56–62. doi:10.1016/j.tecto.2016.01.016
  6. Zhan, Y., Hou, G.T., Hari, K. R. et al., 2014. Geochemical and Isotopic Constraints on the Evolution of Late Paleozoic Dyke Swarms in West Junggar, Xinjiang, China. Journal of Asian Earth Sciences. http://dx.doi.org/10.1016/j.jseaes.2014.07.012.