Nathan A Simmons

Staff Scientist
Atmospheric, Earth, and Energy Division
Email: simmons27@llnl.gov
Phone: +19254222473

Education

  • Ph.D., Geophysics, University of Texas at Austin, 2007
  • M.Sc., Geoscience, Texas Tech University, 2000
  • B.S., Geophysics, Texas Tech University, 1998

Research Interests

Imaging the Earth on global, regional, and multiple resolution scales using seismic and other geophysical constraints including geodynamic and mineral physics. The objectives are multi-fold including the development of realistic Earth models that allow for improved seismic event monitoring capabilities and a better understanding of the evolution of the Earth.

Publications

Simmons, N.A., A.M. Forte and S.P Grand, "Joint seismic, geodynamic and mineral physical constraints on three-dimensional mantle heterogeneity: Implications for the relative importance of thermal versus compositional heterogeneity," Geophysical Journal International 177, 1284 (2009).

Moucha, R., A.M. Forte, D.B. Rowley, J.X. Mitrovica, N.A. Simmons and S.P. Grand, "Mantle convection and the recent evolution of the Colorado Plateau and the Rio Grande Rift Valley," Geology 36, (2008).

Moucha, R., A.M. Forte, J.X. Mitrovica, D.B. Rowley, S. Quere, N.A. Simmons and S.P. Grand, "Dynamic topography and long-term sea-level variations: there is no such thing as a stable continental platform," Earth and Planetary Science Letters 271, (2008).

Simmons, N.A., A.M. Forte and S.P Grand, "Thermochemical structure and dynamics of the African superplume," Geophysical Research Letters 34, (2007).

Simmons, N.A., "Global-scale mantle heterogeneity from seismic and geodynamic constraints," Ph.D. Thesis, University of Texas, Austin (2007).

Forte, A.M., J.X. Mitrovica, R. Moucha, N.A. Simmons and S.P. Grand, "Descent of the ancient Farallon slab drives localized mantle flow below the New Madrid Seismic Zone," Geophysical Research Letters 34, (2007).

Simmons, N.A., A.M. Forte and S.P. Grand "Constraining mantle flow with seismic and geodynamic data: A joint approach," Earth and Planetary Science Letters 246, 109 (2006).

Simmons, N.A. and S.P. Grand, "Partial melting in the deepest mantle," Geophysical Research Letters 29, (2002).

Simmons, N.A. and H. Gurrola, "Seismic evidence for multiple discontinuities near the base of the transition zone," Nature, 405, 559 (2000).

Simmons, N.A., "The upper mantle transition zone beneath southern California," Masters Thesis, Texas Tech University, Lubbock (2000).