Ben Johnson

  • Assistant Professor
  • (he/him/his)



164 Science I Hall
2237 Osborn Drive
Ames IA



I am a geologist and geochemist with broad interests that span Earth History, Earth System Science, and Astrobiology. I use a variety of rock archives, including chemical sediments, glacial tills, and igneous rocks as records of the interactions between life, the oceans, the atmosphere, and the solid Earth over deep time. I access these archives through field work, analytical and isotope geochemistry, and numerical modeling to investigate deep time questions about Earth history.

Teaching Interests

Earth History, Sedimentary Geology, Field Camp, Astrobiology, Isotope Geochemistry


Ph.D. Earth and Ocean Sciences, University of Victoria, 2017

M.Sc. Geology and Geophysics, University of Utah, 2009

B.Sc. Geology, University of Puget Sound, 2006

Selected Publications

  • Johnson, Benjamin W. and Stu ̈eken, E. E. (invited). Precambrian Evolution of the Nitrogen Cycle. Treatise on Geochemistry.
  • Johnson, Benjamin W., Mettam, C., and Poulton, S. W. (2022). Combining nitrogen isotopes and redox proxies strengthens paleoenvironmental interpretations: examples from Neoproterozoic Snowball Earth sediments. Frontiers in Earth Sci- ence, page 825
  • Johnson, Benjamin W., Wing, B. A., and Abbott, L. (2022). Hydrothermal ore deposits record the oxygen isotope composition of meteoric paleo-waters in the San Juan Volcanic Field, Colorado, USA. Geophysical Research Letters, 49:e2022GL098159
  • Johnson, Benjamin W. and Wing, B. A. (2020). Limited Archaean continental emergence reflected in an early Archaean 18O-enriched ocean. Nature Geoscience, 13:243–248
  • Johnson, Benjamin W. and Goldblatt, C. (2018). EarthN: a new Earth System nitrogen cycle model. Geochemistry, Geophysics, Geosystems, 19(8):2516–2542