John Sarao


My research interests through my Master’s degree involved using calcareous nannofossils as a paleoceanographic proxy to interpret surface water conditions of the Mid-Maastrichtian Pierre Sea (Cretaceous Western Interior Seaway).

After my Masters, I spent 8.5 years as a calcareous nannofossil biostratigrapher in the oil industry.  Through this work I gained significant experience, having conducted wellsite nannopaleontology on >25 Gulf of Mexico wells, and wellsite nannopaleontology on numerous wells in East Africa.  I have also analyzed an additional +100 wellbores from diverse regions worldwide including Gulf of Mexico, Africa, Europe (Paris Basin), South America (Colombia), Trinidad (Columbus Basin), and Vietnam (Nam Con Son Basin).

In addition to biostratigraphy, my doctoral work will focus on the geochemical applications of carbonate sediment (specifically calcareous nannofossils). Using samples from the scientific cruises outlined below, I hope to test the role of the equatorial and subtropics in the changes seen in pCO2 on the glacial to interglacial timesclae.

Additional interests include paleoceanography, paleoclimatology, isotope geochemistry, organic geochemistry (Alkenones), and global biogeochemical cycles.


International Ocean Discovery Program (IODP) Expedition 385: Guaymas Basin Tectonics and Biosphere: Sailed as the Team Lead for the micropaleontology group and aided in identification of key nannofossil marker species for age control.

NSF/IODP Expedition 379T (JR100): Extending high resolution paleoclimate records from the Chilean Margin to the Eemian: Sailed as the nannofossil biostratigrapher for the inaugural JR100 research cruise where I identified nannofossil marker species for both age control and paleoenvironmental interpretation. 

Selected Publications

Teske, A., Lizarralde, D., Höfig, T.W., Aiello, I.W., Ash, J.L., Bojanova, D.P., Buatier, M.D., Edgcomb, V.P., Galerne,C.Y., Gontharet, S., Heuer, V.B., Jiang, S., Kars, M.A.C., Khogenkumar Singh, S., Kim, J.-H., Koornneef, L.M.T., Marsaglia, K.M., Meyer, N.R., Morono, Y., Negrete-Aranda, R., Neumann, F., Pastor, L.C., Peña-Salinas, M.E., Pérez Cruz, L.L.,Ran, L., Riboulleau, A., Sarao, J.A., Schubert, F., Stock, J.M., Toffin, L.M.A.A., Xie, W., Yamanaka, T., and Zhuang, G., 2021. Expedition 385 summary. In Teske, A., Lizarralde, D., Höfig, T.W., and the Expedition 385 Scientists, Guaymas Basin Tectonics and Biosphere. Proceedings of the International Ocean Discovery Program, 385: College Station, TX (International Ocean DiscoveryProgram). 

Gezovich, L., Sarao, J., Belanger, C., & Marcantonio, F. 2020. Cross-validation of xsBa and Benthic Foraminiferal Assemblages as proxies of organic matter flux in the Equatorial Pacific. In: Ocean Sciences Meeting; 2020 Feb 16-21.

Griffith, C.M., Sarao, J., Lauckner, L., McCreary, M.E., Miller, B.V., Pope, M.C., & Donovan, A.D. 2020.Correlations, Ages, and Depositional Environments of the Lower Austin Chalk Group in East Texas: Insights From the USGS GC-1 and GC-2 Cores. In: AAPG Convention; 2020 June 7-10.

Waterman, A.S., Center, M.W., George, R.A., Vallette, N.S., Porter Jr, A.F., Reilly, T.M., Weber, R.A., Roederer, R.V., Schmieder, J., Sarao, J.A. and Fillon, R.H., 2012. Neogene biostratigraphic chart: Paleo-Data.

Sarao, J.A. “Invasion of an Oceanic Surface Water Mass into the Mid-Maastrichtian Pierre Epeiric Sea .” Thesis (M.S.)--University of Nebraska--Lincoln, 2009, 2009. Print.

Sarao Jr., J.A., 2005. Questioning Gray Shark Biodiversity in the Atlantic Coastal Plain: Morphometric Analysis of Miocene-Pliocene Shark Teeth. Geological Society of America Abstracts with Programs, v. 37, no.7, p. 134.


M.S. Micropaleontology, University of Nebraska-Lincoln (2009)

B.S. Geology, Virginia Polytechnic Institute and State University (Virginia Tech) (2006)


Graduate Student Teaching Award, Department of Geology and Geophysics Texas A&M University (2021)

International Nannoplankton Association Katharina von Salis Research Fellowship (2019)

Texas A&M College of Geosciences Dr. Tom Tieh Endowed Fellowship (2019)

Geological Society of America Research Grant (2007)

Nebraska Geological Society Yatkola-Edwards Grant (2007)

American Association of Petroleum Geology Match of Yatkola-Edwards Grant (2007)

Virginia Polytechnic Institute and State University Undergraduate Research Award (2006)

Virginia Polytechnic Institute and State University University of Geosciences Academic Excellence Award (2003-2006)


TA courses:

Geol 102: Principles of Geology Lab

Geol 106: Historical Geology

Geol 150: Introduction to the Solid Earth

Geol 152: History of the Earth

Geol 314: Geobiology and Paleontology


Additional Information

Advisor: Denise Kulhanek / Franco Marcantonio

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