Steven Jacobsen

Steven Jacobsen

Professor
Director of Graduate Admissions
Email: steven at
earth.northwestern.edu
847-467-1825
Location: Tech F297/F298

Ph.D. Geophysics; University of Colorado
M.S. Geology; University of Colorado
B.A. Geology; University of Colorado

Research Website


Research

Professor Jacobsen is a mineralogist specializing in mineral physics, which applies atomic-scale structure and physical properties of materials to understand global-scale processes in solid-Earth geophysics and geochemistry, planetary science, as well as high-pressure physical chemistry and materials science.

Using diamond-anvil cells, Jacobsen investigates how pressure modifies fundamental properties of materials such as structure, bonding, and elasticity, with emphasis on the role of defects in crystals. Hydrogen defects in minerals, stabilized at high pressures of the deep mantle, could represent the largest geochemical reservoir of H2O in the Earth and influenced the evolution of our habitable planet. Using high-pressure ultrasonic methods, he is developing tools for remote detection of water in the mantle from seismic imaging of the Earth’s interior.  

Other topics in Jacobsen’s lab include properties of novel superhard materials for future technological applications, elastic properties of glasses, spectroscopy of planetary ices, and the role of hydrogen, carbon, and other volatiles in Earth and planetary materials and processes.

Teaching

EARTH 101: Earth Science for the 21st Century
EARTH 300: Earth and Planetary Materials
EARTH 438: Adv. Topics: Mineral Physics

Selected Publications

Childress, L.B. and S.D. Jacobsen (2017) High-pressure high-temperature Raman spectroscopy of kerogen: relevance to subducted organic carbon. American Mineralogist 102, 391-403.

Clark, A.N., C.E. Lesher, S.D. Jacobsen, and Y. Wang (2016) Anomalous density and elastic properties of basalt at high pressure: reevaluating the effect of melt fraction on seismic velocity in the Earth’s crust and upper mantle. Journal of Geophysical Research 121, doi: 10.1002/2016JB012973. 

Liu, X., Y.Y. Chang, S.N. Tkachev, C.R. Bina, and S.D. Jacobsen (2017) Elastic and mechanical softening in boron-doped diamond. Scientific Reports 7, 42921.

Liu, X., X. Chen, H.A. Ma, X. Jia, J. Wu, T. Yu, Y. Wang, J. Guo, S. Petitgirard, C.R. Bina, and S.D. Jacobsen (2016) Ultrahard stitching of nanotwinned diamond and cubic boron nitride in C2-BN composite. Scientific Reports 6, 30518.

Palot, M., S.D. Jacobsen, J.P. Townsend, F. Nestola, K. Marquardt, N. Miyajima, J.W. Harris, T. Stachel, C.A. McCammon, and D.G. Pearson (2016) Evidence for H2O-bearing fluids in the lower mantle from diamond inclusion. Lithos 265, 237-243. 

Qin, F., X. Wu, Y. Wang, D. Fan, S. Qin, K. Yang, and S.D. Jacobsen (2016) High-pressure behavior of natural single-crystal epidote and clinozoisite up to 40 GPa. Physics and Chemistry of Minerals 43, 649-659.

Townsend, J.P., J. Tsuchiya, C.R. Bina, and S.D. Jacobsen (2016) Water partitioning between bridgmanite and postperovskite in the lowermost mantle. Earth and Planetary Science Letters 454, 20-27.

Walsh, J.P.S., S.M. Clarke, Y. Meng, S.D. Jacobsen and D.E. Freedman (2016) Discovery of FeBi2. ACS Central Science 2, 867-871.

Yang, J., J.F. Lin, S.D. Jacobsen, S.N. Tkachev, and V.B. Prakapenka (2016) Elasticity of ferropericlase and seismic heterogeneity in the Earth’s lower mantle. Journal of Geophysical Research 121, doi: 10.1002/2016JB013352.

Zhang, L., J.R. Smyth, J. Allaz, T. Kawazoe, S.D. Jacobsen, and Z. Jin (2016) Transition metals in the transition zone: crystal chemistry of minor element substitution in wadsleyite. American Mineralogist 101, 2232-2330.

Research Interests

  • Mineral Physics
  • Solid-Earth Geophysics and Geochemistry
  • Mineralogy and Petrology

Steven Jacobsen Photos

Gem-diamonds as superhard transparent anvils

View of single-crystal silicate spinel (blue) inside a hard rhenium gasket

Crystal of Yttrium-Aluminum-Garnet between a pair of tweezers

March 16, 2017