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Ryan T Deasy, Ph.D.

I am a Mendenhall fellow based in Reston, Virginia. My work with the Coastal Basement Geology of the Southeastern U.S. Project involves mineralogical, geochemical, and isotopic studies of rocks from deep wells and the production of geologic maps from these data. The list of Publications below is automatically generated and incomplete. Please contact me directly for a copy of my current CV.

Professional Experience

  • 2020-present, Research Geologist | Mendenhall Fellow, U.S. Geological Survey, Reston, Virginia

  • 2018-2020, Research Specialist, Bedrock Mapping, Conn. Dept. of Energy & Environmental Protection, Hartford, Connecticut

  • 2015, Research Assistant, Chemical Analyst, IODP 345 Post-Expedition Award, Bergen, Norway  

  • 2013-2014, Research Assistant, Bedrock Mapping, EDMAP Project #G13AC00087, Connecticut

Education and Certifications

  • Ph.D. in Geological Sciences, minor in Geochemistry, Indiana University, 2019

  • M.S. in Geological Sciences, Indiana University, 2015

  • B.S. in Geological Sciences, Indiana University, 2011

  • B.M. in Music Composition, minor in Philosophy, Indiana University, 2002

Affiliations and Memberships*

  • American Geophysical Union (AGU) member 2012-present

  • Geological Society of America member (GSA) 2012-present

Honors and Awards

  • Geological Society of America Student Research Grant - 2016

  • John & Mary Droste Associate Instructor Award - 2016

  • Marland Pratt Billings and Katherine Fowler-Billings Research Award - 2015

Abstracts and Presentations

  • Deasy, R. and McAleer, R. (2022). Basement infrastructure of northwest Florida revealed by 40Ar/39Ar age spectra of K-feldspar and muscovite. In Geol. Soc. Of Am. Southeastern Section Abstracts with Programs.

  • Deasy, R., Meyer, R., Wintsch, R. (2021). Average fast spread oceanic crustal composition and insights into its plumbing system. In Physics of Volcanoes 2021 Workshop PoV-7 Abstracts with Programs.

  • Meyer, R., Wintsch., R., & Deasy, R. (2021). A new drill core material sample collection strategy for the measurement of average chemical and mineral modal rock compositions. In Space Resources Week 2021 Abstracts with Programs.

  • Deasy, R., & Lupo, M. (2021). Geochemistry and mineralogy of mafic, intermediate, and felsic rocks of the North Florida volcanic series. In Geol. Soc. Of Am. Southeastern Section Abstracts with Programs.

  • Deasy, R. T. Meyer, R., & Wintsch, R. P. (2020). Evolution and composition of the lower crust produced at fast-spreading oceanic margins: insights from the Hess Deep Rift tectonic window. In International Conference on Ophiolites and the Oceanic Lithosphere: Results of the Oman Drilling Project and Related Research Abstracts.

  • Deasy, R. T., Wintsch, R. P., Meyer, R., & Bish., D. (2019). Stepped alteration of lower oceanic crust at Hess Deep from whole rock 87Sr/86Sr data and quantitative modal mineralogy. In AGU Fall Meeting Abstracts.

  • Wathen, B., McAleer, R., Deasy, R. T., & Wintsch, R. P. (2017). Metamorphic Differentiation by dissolution-precipitation creep in fault-rock phyllonites. In 2017 Geol. Soc. of Am. Northeast Section Abstracts with Programs.

  • Deasy, R. T., Bish, D., & Wintsch, R. P. (2016). Mineralogy of clasts and matrices in a Siluro-Ordovician tectonic mélange: new constraints and new complications on pre-Acadian crustal evolution in southern New England. In 2016 Geol. Soc. of Am. Northeast Section Abstracts with Programs, 44-3.

  • Deasy, R. T., Wintsch, R. P., Meyer, R., Bish, D. L., Gasaway, C., & Heimdal, T. (2014, December). Decoupling of Serpentinization and Prehnitization in Lower East Pacific Rise Crust at Hess Deep. In AGU Fall Meeting Abstracts.

  • Deasy, R. T., Wathen, B., & Wintsch, R. P. (2014). EDMAP bedrock geologic map of accreted terranes, western New Haven Quadrangle, CT, USA. In 2014 Geol. Soc. of Am. Annual Meeting Abstracts with Programs, 205-19.

  • Deasy, R. T., Wintsch, R. P., & Jones, L. (2014). A new interpretation of the Maltby Lakes "volcanics" and related rocks, western New Haven Quadrangle, Connecticut, USA. In 2014 Geol. Soc. of Am. Northeast Section Abstracts with Programs, 46-3.

  • Deasy, R. T., Wintsch, R. P. (2013). Reaction and textural softening in a shear zone in the Newtown ortho-gneiss, Sandy Hook, CT. In 2013 Geol. Soc. of Am. Northeast Section Abstracts with Programs, 43-2.

Science and Products

A channel sampling strategy for measurement of mineral modal and chemical composition of drill cores: Application to lower oceanic crustal rocks from IODP Expedition 345 to the Hess Deep rift

We report a new sampling strategy for collecting representative samples of drill core. By splitting the core with a diamond saw into working and archive halves, the saw cuttings constitute a “channel” sample, the best subsample from which to obtain an average mineralogical and geochemical composition of a core. We apply this procedure to sampling core of the lower oceanic crust in the Hess Deep ob
Authors
Robert P. Wintsch, Romain Meyer, David Bish, Ryan Thomas Deasy, Toshio Nozaka, Carley Johnson
By
Florence Bascom Geoscience Center

Non-USGS Publications**

Deasy, R. T., Wintsch, R. P., & Meyer, R. (2021). Bulk composition of fast-spreading oceanic crust: insights from the lower cumulates of the East Pacific Rise and from Cocos-Nazca Rift basalts, Hess Deep. Journal of Petrology.
Deasy, R. T., Wintsch, R. P., (2020). Draft bedrock geological map of the Essex 7.5 Minute Quadrangle, Middlesex county, Connecticut, U.S.A. Connecticut Geological and Natural History Survey, Department of Energy and Environmental Protection, Hartford, CT. CGNHS OF20-1, 1:24,000 scale.
Deasy, R. T., Wintsch, R. P., (2019). Draft bedrock geological map of the Deep River Quadrangle, New London and Middlesex counties, Connecticut, U.S.A. Connecticut Geological and Natural History Survey, Department of Energy and Environmental Protection, Hartford, CT. CGNHS OF19-1, 1:24,000 scale.
Deasy, R. T., Wathen, B., & Wintsch, R. P., (2017). Bedrock geology of the Paleozoic rocks of western New Haven quadrangle, Connecticut. The Journal of Maps, 13(2), 632-643.
Basu, A., Bickford, M. E., & Deasy, R. (2016). Inferring tectonic provenance of siliciclastic rocks from their chemical compositions: a dissent. Sedimentary Geology, 336, 26-35.
Deasy, R. T., Wintsch, R. P., Wathen, B., McAleer, R., Bish, D., & Meyer, R. (2015). Tectonic slivers of oceanic terranes: Sheeted dikes and sheared gabbros in south-central Connecticut. In Gilmore, M. S., & Resor, P. G. (Eds.), Guidebook to field trips in Connecticut and Massachusetts (1–24). Middletown, CT: Wesleyan University.
Wathen, B., Helou, C., Wintsch, R.P., Deasy, R.T., Yi, K., McAleer, R., Matthews, J. (2015). Deformation spanning 200 million years along the peri-Laurentian (Pumpkin Ground Orthogneiss) Buttress and the East Derby Shear Zone, South-central Connecticut. In Gilmore, M.S., and Resor, P.G. (Eds.), Guidebook to field trips in Connecticut and Massachusetts (153-172), Middletown, CT: Wesleyan University.

**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.

Science and Products

A channel sampling strategy for measurement of mineral modal and chemical composition of drill cores: Application to lower oceanic crustal rocks from IODP Expedition 345 to the Hess Deep rift

We report a new sampling strategy for collecting representative samples of drill core. By splitting the core with a diamond saw into working and archive halves, the saw cuttings constitute a “channel” sample, the best subsample from which to obtain an average mineralogical and geochemical composition of a core. We apply this procedure to sampling core of the lower oceanic crust in the Hess Deep ob
Authors
Robert P. Wintsch, Romain Meyer, David Bish, Ryan Thomas Deasy, Toshio Nozaka, Carley Johnson
By
Florence Bascom Geoscience Center

Non-USGS Publications**

Deasy, R. T., Wintsch, R. P., & Meyer, R. (2021). Bulk composition of fast-spreading oceanic crust: insights from the lower cumulates of the East Pacific Rise and from Cocos-Nazca Rift basalts, Hess Deep. Journal of Petrology.
Deasy, R. T., Wintsch, R. P., (2020). Draft bedrock geological map of the Essex 7.5 Minute Quadrangle, Middlesex county, Connecticut, U.S.A. Connecticut Geological and Natural History Survey, Department of Energy and Environmental Protection, Hartford, CT. CGNHS OF20-1, 1:24,000 scale.
Deasy, R. T., Wintsch, R. P., (2019). Draft bedrock geological map of the Deep River Quadrangle, New London and Middlesex counties, Connecticut, U.S.A. Connecticut Geological and Natural History Survey, Department of Energy and Environmental Protection, Hartford, CT. CGNHS OF19-1, 1:24,000 scale.
Deasy, R. T., Wathen, B., & Wintsch, R. P., (2017). Bedrock geology of the Paleozoic rocks of western New Haven quadrangle, Connecticut. The Journal of Maps, 13(2), 632-643.
Basu, A., Bickford, M. E., & Deasy, R. (2016). Inferring tectonic provenance of siliciclastic rocks from their chemical compositions: a dissent. Sedimentary Geology, 336, 26-35.
Deasy, R. T., Wintsch, R. P., Wathen, B., McAleer, R., Bish, D., & Meyer, R. (2015). Tectonic slivers of oceanic terranes: Sheeted dikes and sheared gabbros in south-central Connecticut. In Gilmore, M. S., & Resor, P. G. (Eds.), Guidebook to field trips in Connecticut and Massachusetts (1–24). Middletown, CT: Wesleyan University.
Wathen, B., Helou, C., Wintsch, R.P., Deasy, R.T., Yi, K., McAleer, R., Matthews, J. (2015). Deformation spanning 200 million years along the peri-Laurentian (Pumpkin Ground Orthogneiss) Buttress and the East Derby Shear Zone, South-central Connecticut. In Gilmore, M.S., and Resor, P.G. (Eds.), Guidebook to field trips in Connecticut and Massachusetts (153-172), Middletown, CT: Wesleyan University.

**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.

*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government