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E. Troy Rasbury

Associate Professor
Office: ESS 320
Phone: 631-632-1488

Website: Troy Rasbury

B.S., Midwestern State University, 1984 
M.S., Tulane University, 1990 
Ph.D., SUNY Stony Brook, 1998 
Assistant Professor at Queens College 1998-1999 
Faculty member at Stony Brook starting Fall 1999

Two of the most fundamental problems in geology are time resolution and Earth’s history recorded in sedimentary archives. My career-long focus has been in exploring the potential for directly dating sedimentary carbonates with U-Pb. This involves the study of carbonates to understand the environmental conditions in which they formed. In addition to careful petrographic study, I approach sample selection for U-Pb dating from several directions including 1) a focus on the controls on U speciation in depositional environments and how this controls its incorporation into carbonates, 2) trace element mapping, particularly taking advantage of my proximity to the NSLS II, 3) fission track maps, and 4) autoradiography. Laser ablation methods have dramatically improved our ability to identify carbonates with potential for dating. I have been involved in the early innovations for using laser ablation ICPMS dating of carbonates with colleagues from the British Survey. We have provided the most widely used LA U-Pb reference material- WC-1 (Roberts et al., 2017). In addition to carbonates, the availability of the LA-ICPMS has allowed me and my group to explore other archives that might be dateable by U-Pb including fluorite and nacrite (Piccione et al., 2019).

A major theme of my research involves understanding the history of ocean chemistry. This started with my interest in what controls uranium incorporation in carbonates, and has expanded to other elemental and isotopic records. In the past few years I have begun to study boron isotopes, both in carbonates to get at past fluids, and in modern surface and groundwaters. My work with former NSF post doc Cara Thompson and former Ph.D. student Shelbie Legett on fossil brachiopods shows major shifts in boron isotopes in seawater in the Paleozoic. Ongoing research is expanding the boron record and adding Ca and Li isotopes to better understand what controls the changes. Additionally, I work with synchrotron XRF for elemental mapping of echinoderm fossils to follow up on work that shows they are archives of seawater chemistry. Work with Paul Northrup in the tender energy range is allowing us to examine Mg, S, and Sr, and to consider speciation as well as abundance.

The acquisition of a NuII MC-ICPMS has not only opened up exciting new opportunities to understand the environmental records of carbonates but has also provided expanded capability to work on modern water systems. Collaborating with John Luczaj I have applied boron isotopes in groundwaters across Wisconsin, where the data show a remarkable gradient in concentrations and isotope composition implying a source from brines of the Michigan Basin to the west. Work with former MS student Mengqu Han in the Mono Basin has revealed extreme concentrations in the lake, and isotope ratios that are similar to that of the average spring waters. Ongoing work with SOMAS collaborators, Gil Hanson and students from the Geoprep program on Long Island surface and groundwaters is focused on the potential for boron isotopes to track the sources of nitrate and other natural and anthropogenic contaminates to groundwaters.

Selected Publications  

Rasbury, E. Troy, Present, Theodore M., Northrup, Paul, Tappero, Ryan V., Lanzirotti, Antonio, Cole, Jennifer M., Wooton, Kathleen M. and +Hatton, Kevin, Tools for uranium characterization in carbonate samples: case studies of natural U–Pb geochronology reference materials, Geochronology, 3, 1–20, 2021,

Alfaro, Aristides, Gazel, Esteban, White, William M., Jicha, Brian, and Rasbury, Troy. 2021, Unravelling the genesis of young continental-arc shoshonites in the Talamanca Cordillera, Costa Rica, Lithos,

Li, Xianghui, Wang, Jingyu, Rasbury, Troy, Zhou, Min, Wei, Zhen, and Zhang, Chaokai, 2020, Early Jurassic climate and atmospheric CO2 concentration in the Sichuan paleobasin, southwestern China, Climate of the Past, 15, 2055-2074,

Legett, S. A., Rasbury, E. T., Grossman, E. L., Hemming, N., G., and Penman, D. E., 2020, The brachiopod d 11B record across the Carboniferous-Permian climate transition, Paleoceonography and Paleoclimatology,

Tamborski, J., Brown, C., Bokuniewicz, H., Cochran, J. K., and Rasbury E. T., 2020, Investigating boron isotopes for identifying nitrogen sources supplied by submarine groundwater discharge to coastal waters, Frontiers in Environmental Science,

Sandstrom, M. R., O’Leary, M. J., Barham, M., Cai, Y., Rasbury, E. T., Wooton, K. M., and Raymo, M. E., 2020, Age constraints on surface deformation recorded by fossil shorelines at Cape Range, Western Australia, Geological Society of America Bulletin,

McHugh, C. M., Seeber, L., Rasbury, T. Strasser, M. Kioki, A., Kanamatsu, T. Ikehara, K. and Usami, K., 2020, Isotopic and Sedimentary Signature of Megathrust Ruptures Along the Japan Subduction Margin, Marine Geology, 428, 106283,

Machlus. M.L., Shea, E.K., Hemming, S., Ramezani, J., Rasbury, E. Troy, 2020, An assessment of the Fire Clay tonstein as a Carboniferous U-Pb and Ar-Ar standard: Chemical Geology,

Smit, Matthijs, Scherstén, Anders, Næraa, Tomas, Emo, Robert, Scherer, Erik, Sprung, Peter, Bleeker, Wouter, Mezger, Klaus, Maltese, Alessandro, Cai, Merry, Rasbury, Troy, Whitehouse, Martin, 2019, Formation of the Archean continental crust constrained by boron isotopes: Geochemical Perspectives Letters, 12, 23-26.

Parrish, Judith T., Rasbury, E. Troy, Chan, Marjorie A., Hasiotis, Stephen T., 2019, Earliest Jurassic U-Pb ages from carbonate deposits in the Navajo Sandstone, southeastern Utah, USA, Geology,

Piccione*, Gavin, Rasbury E. Troy, Elliot, Brent A., Kyle, J. Richard, Jaret, Steven J., Acerbo, Alvin, Lanzirotti, Antonio, Northrup, Paul, Wooton, Kathleen, Parrish, Randall R., 2019, Vein fluorite U-Pb dating demonstrates post-6.2 Ma rare earth element mobilization associated with Rio Grande rifting, Geosphere, 15,

Jaret+, Steven J., Harris, R. Scott, Rasbury E. Troy, 2019, A New Technique for Ir Concentration Measurements via ICP-MS, Chemical Geology, 528, 10.1016/j.chemgeo.2019.08.003.

Jaret, Steven J., Hemming, S. R., Rasbury, E. T., Thompson, L. M., Glotch, T. D., and Spray, J. G., 2018, Context matters – Ar–Ar results from in and around the Manicouagan Impact Structure, Canada: Implications for martian meteorite chronology: Earth and Planetary Science Letters, 501, 78-89.

Bahadori, Alireza, Holt, William E., and Rasbury, E. Troy, 2018, Reconstruction Modeling of Crustal Thickness and Paleo-elevation of Western North America Since 36 Ma, Geosphere, 14, 1207-1231. 

Benison, Kathleen C., Difrisco, Adam, Knapp, Jonathan P., and Rasbury E. Troy, 2018, The Permian Minnekahta Limestone: A Saline Lake Gypsum Replaced by Calcite, Mountain Geologist, 55, 59-73.

Lawson, Michael, Shenton, Brock J., Stolper, Daniel A., Eiler, John M., Rasbury E. Troy, Becker, Thomas P., Phillips-Lander, Charity M., Buono, Antonio S., Becker, Stephen P., Pottorf, Robert, Gray, Gary G., Yurewicz, Don and Gournay, Jonas, 2017, Deciphering the diagenetic history of the El Abra Formation of Eastern Mexico using reordered clumped isotope temperatures and U-Pb dating, Geological Society of America Bulletin, 130, 617-629.

Rasbury, E. T., and Hemming, N. G., 2017, Boron isotopes in marine calcium carbonate shells: A proxy for paleo-pH and ancient atmospheric CO 2: in Elements, Boron Light and Lively edited by Edward S. Grew guest editor, Vol. 13, pp. 243–248.

Quade, J., Rasbury, E. T., Huntington, K., Hudson, A.M., Vonhof, H., Anchukaitis, K., Betancourt, J. , Latorre, C., Pepper, M., 2017, An 11.5-million year record of hyperaridity from the central Atacama 2 Desert, Chile, Chemical Geology, 466 pp 41–56.

Roberts, N. M. W., Rasbury, E. T., Parrish, R. R., Smith, C. J., Horstwood, M. S. A., and Condon, D. J., 2017, A calcite reference material for LA-ICP-MS Geochronology: Geochemistry, Geophysics, Geosystems, 18, 2807-2814. doi 10.1002/2016GC006784

Wortham, B. E., Wong, C. I.,  Silva, L. C. R., McGee, D., Montañez, I. P., Rasbury, E. T., Cooper, K. M., Sharp, W. D., Glessner, J. G., and Santo, R. V.,  2017, Assessing response of local moisture conditions in central Brazil to variability in regional monsoon intensity using speleothem 87Sr/ 86Sr values: Earth and Planetary Science Letters 463, 310–322.

Hulett, S. R. W., Simonetti, A., Rasbury E. T. and Hemming, N. G., 2016, Boron Isotopic Evidence for Input of Subducted Crustal Components in Carbonatite Melts, Nature Geoscience.  9, 904-908 doi:10.1038/ngeo283

Blackburn, T. J., Olsen, P. E., Bowring, S. A., McLean, N. M., Kent, D. K., Puffer, J. McHone, G., Rasbury, E. T., and Et-Touhami, M., 2013, Zircon U-Pb Geochronology Links the End-Triassic Extinction with the Central Atlantic Magmatic Province: Science. 340, 941-944.

Penman, D. E., Hönisch, B., Rasbury E. T., Hemming N. G., and Spero, H. J., 2013, Boron, carbon, and oxygen isotopic composition of brachiopod shells: intra-shell variability, controls, and potential as a paleo-pH recorder: Chem Geol. 340, 32-39.

Wilson, Janette, McLennan, Scott M., Glotch, Timothy D., Rasbury, E. Troy, Gierlowski-Kordesch, Elizabeth H., Tappero, Ryan V., 2012, Pedogenic hematitic concretions from the Triassic New Haven Arkose, Connecticut:  Implications for understanding Martian diagenetic processes, Chemical Geology, 312, 195-208   DOI: 10.1016/j.chemgeo.2012.04.013 

Ludvigson, G.A., Joeckel, R.M., Gonzalez, L.A., Gulbranson, E.L., Rasbury, E.T., Hunt, G.J., Kirkland, J.I., and Madsen, S., 2010, Correlation of Aptian-Albian Carbon Isotope Excursions in Continental Strata of the Cretaceous Foreland Basin, Eastern Utah,USA: Journal of Sedimentary Research,  80,  955-974.

Rasbury, E. T., and Cole, J., M., 2009, Direct Dating of Geologic Events: U-Pb Dating of Carbonates: Reviews of Geophysics, v. 47, RG3001, doi: 10.1029/2007RG000246.

Druschke, P., Hanson, A. D., Wells, M. L., Rasbury E. T., and Stockli, D. F., 2009, Synconvergent surface-breaking normal faults of Late Cretaceous age within the Sevier hinterland, east-central Nevada: Geology, v., p. 447-450

Folk, R. L., and Rasbury, E. T., 2007, Nanostructure of palygorskite/sepiolite in Texas calcihe: Possible bacterial origin: Carbonates and Evaporites, v. 22, p. 113-122.

Rasbury, E. T., Gierlowski-Kordesch, E. H., Cole, J. M., Sookdeo, C., Spataro, G., Nienstedt, J., 2006, Calcite Cement Stratigraphy of a Non-Pedogenic Calcrete in the Triassic New Haven Arkose (Newark Supergroup): Geological Society of America Spec. Pub 416: Paleoenvironmental Record and Applications of Calcretes and Palustrine Carbonates. p. 203-221.

Kelly, S. D., Rasbury E. T., Chattopadhyay, S., Kropf, A. J., Kemner, K. M., 2006, Evidence of a Stable Uranyl Site in Ancient Organic-Rich Calcite:Environmental Science &Technology,  40,  2262-2268.

Cole, J. M., Rasbury, E. T., Hanson, G. N., Montañez, I. P., Pedone, V. A., 2005, Using U-Pb ages of Miocene tufa for correlation in a terrestrial succession, Barstow Formation, California: Geological Society of America Bulletin, 117, 276-287.

Rasbury, E. T., Ward, W. B., Hemming, N. G., Li, H., Dickson, J. A. D., Hanson, G. N., Major, R. P., 2004, Concurrent U-Pb age and seawater 87Sr/86Sr value of marine cement: Earth and Planetary Science Letters, 221, 355-371.

Cole, J. M., Rasbury, E. T., Montañez, I. P., Pedone, V. A., Lanzirotti, A., Hanson, G. N., 2004, Petrographic and trace element analysis of uranium-rich tufa calcite, middle Miocene Barstow Formation, California: Sedimentology, 51, 433-453.

Becker, M. L., Rasbury, E. T., Meyers, W. J., Hanson, G. N., 2004, U-Pb calcite age of the Late Permian Castile Formation, Delaware Basin: constraint on the age of the Permian-Triassic Boundary? Reply to a comment by Ian Metcalfe: Earth and Planetary Science Letters, 217, 469-471.

Cole, J. M., Nienstedt, J., Spataro, G., Rasbury, E. T., Lanzirotti, A., Celestian, A. J., Nilsson, M., Hanson, G. N., 2003, A method for determining relative uranium concentrations in geological samples on a hand specimen scale: Chemical Geology, 193, 127-136.

Folk, R. L. and Rasbury, E. T., 2002, Nanometer-scale spheroids on sands, Vulcano, Sicily: possible nannobacterial alteration: Terra Nova, 14, 467-475.

Becker, M. L., Rasbury, E. T., Meyers, W. J., Hanson, G. N., 2002, U-Pb calcite age of the Late Permian Castile Formation, Delaware Basin: constraint on the age of the Permian-Triassic Boundary?: Earth and Planetary Science Letters, 203, 681-689.

Becker, M. L., Cole, J. M., Rasbury, E. T., Pedone, V. A., Montañez , I. P., Hanson, G. N., 2001, Cyclic variations of uranium incorporation in tufa from the Miocene Barstow Formation, Rainbow Basin, Mojave, California: Geology, 29, 139-142.

Rasbury, E. T., Meyers, W. J., Hanson, G. N., Goldstein, R. H., Saller, A. H., 2000, Relationship of uranium to petrography of caliche paleosols with application to precisely dating the time of sedimentation: Journal of Sedimentary Research, 70, 604-618.

Hemming, S. R. and Rasbury, E. T., 2000, Pb isotope measurements of sanidine monitor standards: Implications for provenance analysis and tephrochronology: Chemical Geology, 165, 331-337.

Saller, A.H., Dickson, J.A.D., Rasbury, E.T., Ebato, T. 1999, Effects of long-term accommodation changes on short-term cycles, late Paleozoic platform limestones, West Texas: in Harris, Saller, and Simo, eds, SEPM Special Publication No. 63, Introduction to advances in carbonate sequence stratigraphy- application to reservoirs, outcrops and models, p. 227-246.

Rasbury, E. T., Hanson, G. N., Meyers, W. J., Holt, W. E., Goldstein, R. H., Saller, A. H., 1998, U-Pb dates of paleosols: Constraints on late Paleozoic cycle durations and boundary ages: Geology, 26, 403-406.

Wang, Z. S., Rasbury, E. T., Hanson, G. N., Meyers, W. J., 1998, Dating the time of sedimentation of clastic sedimentary rocks using U-Pb system of calcretes:Geochimica et Cosmochimica Acta, 62, 2823-2835.

Marcantonio, F., Higgins, S., Anderson, R. F., Stute, M., Schlosser, P.,  Rasbury, E. T., 1998, Terrigenous helium in deep-sea sediments: Geochimica et Cosmochimica Acta, 62, 1535-1543.

Rasbury, E. T., Hanson, G. N., Meyers, W. J., Saller, A. H., 1997, Dating of the time of sedimentation using U-Pb ages of paleosol calcite: Geochimica et Cosmochimica Acta, 61, 1525-1529.

Invited Contributions:

Rasbury, E.T., 2013, Uranium-Lead: Diagenetic Processes: in Encyclopedia of Scientific Dating Methods DOI 10.1007/978-94-007-6326-5_22-1, Springer Science+Business Media Dordrecht 2013

Rasbury, E. T. and Cole, J. M., 2006, Directly Dating Sedimentary Rocks: 2006 Paleontological Society Shortcourse at annual GSA meeting in Philadelphia.

Rasbury, E. T., 2002, Geochronology: McGraw-Hill Yearbook of Science & Technology, p. 143-145.

McCall, K., Lanzirotti, A., Rasbury, E. T., 2001, U (VI) Incorporation in Paleosol Calcite: Evidence for Sequestration of U on Geologic Time Scales: NSLS Activity Report 2001

Becker, M. L., Rasbury, E. T., Hanson, G. N., Meyers, W. J., 2001, Refinement in the age of the Carboniferous-Permian boundary based on U-Pb dating of biostratigraphically constrained syn-sedimentary carbonates in the Appalachian region, North America: Carboniferous Newsletter, 19, 18-20.