Environmental Geochemistry, Hydrogeology, Economic Geology
Office: 413 Davis Hall
Ph.D. 1963; Massachusetts Institute of Technology
My major research interests involve aqueous geochemistry and application of stable isotope geochemistry to studies of diagenesis and low grade metamorphism.
Ongoing Research in Yucatan
I. I am conducting research in collaboration with archeologists, geochemists, and soil scientists from other universities to develop and test stable isotopes in cave speleothem laminations as high resolution proxy measures of ancient climate for the past three millennia in the northern Maya Lowlands of Mexico. We hope to demonstrate from isotopic and trace element studies that speleothems can preserve a unique record of short-term events like hurricanes, El Niños, and volcanic eruptions. Speleothem analyses promise annual and perhaps even subannual resolution from which archaeologists can learn much about the specific climatic events that impacted the ancient Maya. Other members of the research group are Timothy Beach (Georgetown University). Clifford Brown (Florida Atlantic University), Bruce Dahlin (Shepherd University), Amy Frappier (Boston College), and their students.
II. Together with Prof. Melissa Lenczewski (Geology), Prof. Melvin Duval (Biology), and students, I am investigating the unique biogeochemical processes taking place within the water columns of selected deep karst sinkholes, known locally as cenotes, which occur in the highly permeable carbonate rocks of the northern Yucatan Peninsula, Mexico. In the chosen cenotes, sulfate, which is derived from seawater, and carbon, derived from forest vegetation, undergo redox reactions mediated by common but elusive organisms including dissimilatory sulfate reducing bacteria, photoautotrophic bacteria, and sulfur oxidizing bacteria, all of which are essential to the operation of worldwide geochemical cycles of carbon, oxygen, and sulfur. Despite their importance and abundance, the behavior of the target communities of organisms is relatively poorly known because they thrive in environments free or nearly free of molecular oxygen. The water columns of the selected cenotes are highly unusual because they have been demonstrated to provide steady-state zones of varying redox potential that are wide enough to be sampled with relative efficiency. We are evaluating distinctive physical and chemical differences (such as size, light availability, interface depth, turbidity, nutrient sources, and water velocity) between the selected cenotes in order to identify and evaluate the importance of environmental factors to these important but elusive communities of microbial organisms.
III. For years I have been acquiring geochemical data from the karst aquifer of the northern Yucatan peninsula, Mexico that can be used for groundwater model calibration. These data include oxygen and deuterium isotopes of hurricane precipitation from Hurricane Isadore (and inevitable future hurricanes). The northern Yucatan aquifer is particularly well suited for this study.
• It has a relatively simple structure consisting of a "layer cake" stratigraphy interrupted by distinct fault and fracture systems that control groundwater flow.
• It has well-defined sources of groundwater ions, including a seawater intrusion and both carbonate aquifer rocks and buried evaporite rocks that provide SO4, Cl, Sr, and other ions that are natural tracers. Sr isotopes, are also modeled, make Sr a powerful tracer species.
• Whereas Yucatan has a good road network, permitting access, population and industrial development are relatively low, large portions of the aquifer system are still relatively undisturbed by human activity.
• Coastal test sites for model calibration range from pristine (Bocas de Dzilam), little developed (Celestun), moderately developed (Dzilam Bravo), populous and polluted (Chelem/Progreso) to frenetically overdeveloped (Cancun/Tulum).
Note: PDF copies of several of these publications are available from the author. (email@example.com)
Perry, Eugene; Adina Payton, Bianca Pedersen, Guadalupe Velazquez-Oliman (2009) Groundwater geochemistry of the Yucatan Peninsula, Mexico: Constraints on stratigraphy and hydrogeology. Journal of Hydrology 367, 27-40.
Perry, E. C. and Lefticariu, L. (2007) Formation and geochemistry of precambrian chert. In: Treatise on Geochemistry, Holland, H. and Turekian, K. eds. V. 7. Sediments, Diagenesis, and Sedimentary Rocks, McKenzie, F. T. ed. Elsevier. (2nd Edition extensively revised, published online.)
Lefticariu, Mihai, Perry, Eugene C., Ward W.C., and Lefticariu, L. (2006) Post-Chicxulub depositional and diagenetic history of the northwestern Yucatan Peninsula, Mexico. Sedimentary Geology, 183, pp. 51-70.
Perry, E.C., Velazquez-Oliman, and Socki, R. A. (2003) Hydrogeology of the Yucatan. 21st Symposium on Plant Biology. Arturo Gomez Pompa and Scott Fedick editors. The Haworth Press, Inc., 10 Alice Street, Binghamton, NY. Chapter 7; p. 115-138 .
Socki, R. A.; Perry, E. C., and Romanek, C. S. (2002) Stable isotope systematics of two cenotes from the northern Yucatan Peninsula, Mexico. Limnology and Oceanography, 47, p. 1808-1818.
Perry, E.C., Velazquez-Oliman, G., and Marin, L. E. (2002) The Hydrogeochemistry of the Karst Aquifer System of the Northern Yucatan Peninsula, Mexico. International Geology Review, 44, p. 191-221.
Perry, E.C., and Velazquez-Oliman, G., 1996, The hydrogeology of the northern Yucatan Peninsula, Mexico, with special reference to coastal processes: LOICZ (Land Ocean Interactions in the Coastal Zone) Ground Water Discharge in the Coastal Zone, in Proceedings of an International Symposium, LOICZ/R&S/96-8 [Buddemeier, R.W., ed., 179 p.], p. 92-97.