Dr. Mohammed S. Hashim
USC Wrigley Ballmer Initiative Postdoctoral Fellow
Department of Earth Sciences
University of Southern California
Guest Investigator
Department of Marine Chemistry and Geochemistry
Woods Hole Oceanographic Institution
Contact Information:
hashimm@usc.edu
Mohammed.hashim@whoi.edu
Current Address:
3651 Trousdale Pky
Los Angeles, CA 90089
ZHS 223
Research Interests
I am interested in the ocean today and throughout Earth history, focusing specifically on the carbonate chemistry of seawater. Some examples of my current research focuses are:
- Exploring the roles of calcium carbonate minerals in the oceanic carbon cycle.
- Quantifying the impact of sub-seafloor processes on ocean chemistry.
- Developing and testing ocean-based carbon sequestration techniques.
My current and previous projects focus on fish produced carbonates in the North Atlantic near Bermuda, sub-seafloor carbon cycling in the Baffin Bay near Greenland glaciated margin, and carbonate sediments on the slope of the Great Bahama Bank. I have also cultured coccolithophores in the lab, and conducted experiments to study the formation, alteration, and dissolution of carbonate minerals (aragonite, calcite, and dolomite) to constrain trace element incorporation and isotope fractionation using experiments. So far, I have been focusing on iodine, barium, and sulfur. More recently, my research has been focusing on ocean alkalinity enhancement as an approach to sequester carbon in the ocean and chemical engineering approaches to generate alkalinity from carbonate rocks.
I am always excited to chat about science, ocean, and carbonates, so please don't hesitate to reach out!
Selected Peer-Reviewed Publications
Hashim, M., Marx, L., Klein, F., Dean, C., Burdige, E., Hayden, M., McCorkle, D., and Subhas, A. 2025. Mineral Formation during Shipboard Ocean Alkalinity Enhancement Experiments in the North Atlantic, EGUsphere [preprint], https://doi.org/10.5194/egusphere-2025-988.
M. Yaqoob, M. Y. Ansari, M. Ishaq, I. S. A. J. Jayachandran, M. Hashim and T. D. Seers. 2025. MicroCrystalNet: An Efficient and Explainable Convolutional Neural Network for Microcrystal Classification using Scanning Electron Microscope Petrography. IEEE Access. https://doi.10.1109/ACCESS.2025.3552626.
Hashim, M., Subhas, A., Kaczmarek, S., Gemakrisindo Wolfram Naa, and Bish, D. 2024. A Process-based Geochemical Framework for Carbonate Sediments During Marine Diagenesis. Geochimica et Cosmochimica Acta. https://doi.org/10.1016/j.gca.2024.05.023
Hashim, M., Burke, J., Hardisty, D., and Kaczmarek, S.E. 2022. Iodine Incorporation into Dolomite: Experimental Constraints and Implications for the Iodine Redox Proxy and Proterozoic Ocean. Geochimica et Cosmochimica Acta. https://doi.org/10.1016/j.gca.2022.10.027
Hashim, M. and Kaczmarek, S.E. 2022. Rhombic Calcite Microcrystals as a Textural Proxy for Meteoric Diagenesis. Scientific Reports. https://doi.org/10.21203/rs.3.rs-803597/v
Hashim, M. and Kaczmarek, S.E. 2021. The Transformation of Aragonite to Calcite in the Presence of Magnesium: Implications for Marine Diagenesis. Earth and Planetary Science Letters, v. 574., no. 117166. Doi: https://doi.org/10.1016/j.epsl.2021.117166
Hashim, M. and Kaczmarek, S.E, 2020. Experimental Stabilization of Carbonate Sediments to Calcite: Insights into the Depositional and Diagenetic Controls on Calcite Microcrystal Texture. Earth and Planetary Science Letters. vol. 538, no. 116235. https://doi.org/10.1016/j.epsl.2020.116235
Selected Awards and Academic Honors
- 2025: Wrignly Ballmer Initiative Postdoctoral Fellowship, University of Southern California
- 2022: NSF Ocean Sciences Postdoctoral Research Fellowship
- 2022: NSF Earth Sciences Postdoctoral Research Fellowship (award declined by me due to the acceptance of another award)
- 2022: Woods Hole Oceanographic Institution Postdoctoral Fellowship
- 2022: Invitation to join Dissertations Symposium in Chemical Oceanography (DISCO) at the University of Hawai'i.
- 2022: Western Michigan University's institutional nominee for the Council of Graduate School’s Dissertation Award in the. Mathematics, Physical Sciences, and Engineering category
- 2021: Outstanding Student Presentation Award (OSPA) at the American Geophysical Union (AGU) Fall Meeting
- 2021: Schlanger Ocean Drilling Fellowship, U.S. Science Support Program (funded by NSF)
- 2021: Best Student Talk Award (Ph.D. category), Midwest Geobiology Symposium, Indianapolis, IN
- 2021: All-University Graduate Research and Creative Scholar Award (Ph.D. category), Western Michigan University
- 2021: Department-Level Graduate Research and Creative Scholar Award (Ph.D. category), Western Michigan University
- 2021: Lloyd and Marilyn Schmaltz Professional Activities Award, Department of Geological and Environmental Sciences, Western Michigan University
Postdoctoral Appointments
Postdoctoral Fellow: 1/2025 - present. Wrigley Ballmer Initiative Postdoctoral Fellowship. University of Southern California
Postdoctoral Fellow: 11/2022 - 12/2024. NSF Ocean Sciences Fellowship. Woods Hole Oceanographic Institution
Postdoctoral Scholar: 6/2022 - 11/2022. WHOI Postdoctoral Scholarship. Woods Hole Oceanographic Institution
Education
Ph.D.: Geosciences. 2022. Western Michigan University, Kalamazoo, Michigan, USA.
B.Sc: Geology. 2012. University of Baghdad, Baghdad, Iraq