Postdoctoral Researchers

Dr. Gavin Piccione (https://gavinpiccione.github.io/) – Postdoctoral Research Associate, 2023-Present

B.S. Geosciences (Summa cum Laude), Stony Brook University, 2016; Ph.D. Earth & Planetary Sciences, University of California Santa Cruz, 2023;

I am a geochemist and geochronologist with broad interests in the processes that link Earth’s climate and hydrosphere through time. My research leverages both traditional and novel terrestrial sedimentary archives to create time-resolved datasets that describe paleoclimate evolution on decadal to million-year timescales. I have applied these methods to reconstruct the rates of Antarctic ice sheet growth and retreat, and the impact of glaciers on global geochemical cycles. While at Brown, I am working with Dr. Daniel Ibarra on projects investigating the temporal variability of hydroclimate in the western US, as well as weathering beneath ice sheets. Before arriving at Brown, I earned my bachelor’s degree (with Honors) in Geoscience at Stony Brook University, and my PhD in Earth and Planetary Science at the University of California Santa Cruz.

Dr. Devon Kerins – Voss Postdoctoral Research Associate, 2024-Present

B.Sc. Civil Engineering, Montana State University, 2015; M.Eng.Sc. Civil Engineering, National University of Ireland, Galway (now University of Galway), 2016; Ph.D. Environmental Engineering and Biogeochemistry, The Pennsylvania State University, 2024

Devon is interested in how climate and land-use change influence terrestrial-aquatic carbon cycling and water quality. Their research employs data-driven and reactive transport models to investigate the interactions between water flow, biogeochemical processes, watershed structure, and external forcings. At Brown University, they will work with Dr. Dan Ibarra to explore how urbanization, in comparison to less human-impacted areas, alters catchment hydro-biogeochemical functioning and drives changes in water and carbon fluxes to streams. Outside of research you can usually find Devon crocheting a half-finished project, snowboarding down a mountain, standing on the periphery of the pit at a gig, or watching Ghost Adventures.

Research Associate

Hannah Tompkins – Research Associate, 2024-Present

B.S. Geological Sciences, University of Rochester, 2019; M.S. Geosciences, University of Arizona, 2022

Hannah is an isotope geochemist and detail-oriented laboratory manager with a deep appreciation for the meticulous nature of clean lab wet chemistry. At Brown, she has been working in the Trace Metal Laboratory (TML), where she sets up Li isotopes, Sr isotopes, and U-series/U-Th geochronology systems, contributing to a diverse range of projects in the Ibarra group. Her master’s research focused on constraining magmatic equilibrium Zr isotope fractionation in zircon growth experiments. Outside of the lab, you can find her trying a new dance or martial arts class with her cousin and brother, immersed in a science fiction novel, or walking and eating her way around Providence.

Graduate Students

Catherine (Cathy) A. Gagnon (IBES Profile; LinkedIn) – DEEPS Ph.D. Candidate (5th year) – Department of Energy Office of Science Graduate Student Research (SCGSR) program recipient

B.S. Geoscience (w/ hydrogeology concentration), The Pennsylvania State University, 2020

Cathy is a 4th year PhD candidate at Brown University excited about stable isotope geochemistry, terrestrial paleoclimatology, and volcano-sedimentary lithium deposits. Broadly speaking, she uses a variety of stable isotope and mineral characterization methods to understand the geological, environmental, and thermodynamic mechanisms controlling lithium enrichment in sedimentary rocks. Her geological field training involved mapping landscapes in Montana, Wyoming, Utah, and Idaho. Current research interests have since taken her to the arid and semi-arid basins of California, Nevada, and the Atacama desert in Chile. She has conducted research as an intern for Lithium Americas and will be conducting research at the Berkley National Lab this Fall/Winter as part of the DOE SCGSR program. In addition to research, Cathy loves winter hiking, rollerblading, and playing ice hockey around the greater Boston area where she is from. She resides in Norton, MA with her fiancé, little black cat, and kind and goofy dog, Penny.

Sebastian (Seb) Muñoz (IBES Profile) – DEEPS Ph.D. Candidate (4th year) – Brown Presidential Fellow & National Science Foundation Graduate Research Fellow – co-advised by Larry Smith

B.S. Geological Sciences (hydrogeology honors) and B.A. Liberal Arts, University of Texas, Austin, 2018

Sebastian spends all of his time thinking about, studying, or boating on rivers. He is interested in how surface water chemistry will change in response to human activities and climate change. Previous work includes studying rock glaciers contributions to river flows in northern Chile, and understanding surface water and groundwater interactions downstream of a dam in the Colorado River near Austin, TX.

M. Justin Custado (IBES Profile) – DEEPS Graduate Student (3rd year)

B.S. Chemistry, University of the Philippines – Diliman, 2015 & M.S. Environmental Science, University of the Philippines – Diliman, 2021

Riley Havel – DEEPS Graduate Student (3rd year) – National Science Foundation Graduate Research Fellow

Mónica Geraldes Vega – DEEPS Graduate Student (2nd year) – co-advised by Kim Cobb

B.A. Geological Sciences, Mount Holyoke College, 2022

Mónica is broadly interested in paleoclimate, biogeochemistry, and geochronology. Her undergraduate work at Mount Holyoke College involved deciphering siliciclastic paleolake levels of a Jurassic rift lake in Western Massachusetts using physical and geochemical proxies. At Brown, she’s switched gears a little and is into learning about more geologically recent carbonate records via stalagmite samples from the Philippines. She is driven by questions related to tropical paleoclimate and general excitement about learning and sharing knowledge. She is also enjoying her transition from her native Dominican Republic to Providence life, where she is getting better at cooking every day.

Jiquan Chen – Ph.D. Candidate at China University of Geosciences, Beijing (2022- Present) & Visiting Ph.D. Student at Brown University (2023-2024)

Advised by Chengshan Wang, Yuan Gao, and Daniel Ibarra.

Jiquan’s research primarily focuses on terrestrial paleoclimate and paleoenvironment studies in deep time. During his doctoral studies, he has conducted quantitative hydroclimate reconstruction in northeastern East Asia during the late Mesozoic, utilizing clumped and triple oxygen isotope technology. His study materials include pedogenic and lacustrine carbonates, chert, and clays.

Undergraduates

Anna Dubey, Sc.B. Candidate, Ecology, Evolution, & Organismal Biology, Brown University, 2025

Anna is a fourth-year student at Brown studying ecology, evolution, and organismal biology. Her research interests lie at the intersection of evolutionary biology and paleoclimate. She is currently working on a project with Gavin using ostracod data from Silver Lake, CA to produce a temperature record. Other than research, her activities include writing for Encyclopedia Britannica and teaching environmental science to high school students.

Celia Kong-Johnson, A.B. Candidate Geology-Chemistry and Applied Math, Brown University, 2025

Fall 2023 SPRINT|UTRA Award

2023 RSI-WAVE Fellows, Caltech

AGU 2023 Fall Meeting Presentation: Insights into paleorainfall variability in the Philippines using the geochemistry of a speleothem spanning 28 to 51 kyrs BP

2024 Sarah LaMendola Undergraduate Research Award

2024 NSF SOARS Protégé at NSF NCAR, Boulder CO

I am currently a fourth-year at Brown University and am double concentrating in geochemistry and applied math. I am most interested in paleoclimate studies and applying these findings to modern and future climate change research. I am also interested in applying quantitative methods to my research. In Dr. Ibarra’s lab, I analyze carbon and oxygen isotope records in speleothems from Colombia and the Philippines, but mostly the Philippines, to help reconstruct hydroclimate variability in the Indo Pacific Warm Pool region. Outside of academics here at Brown, I enjoy hanging out with my friends and finding places to get dessert or ice cream. I also enjoy visiting and exploring National Parks with my family.

Sarah Levine, Undeclared (Geology-Chemistry or Chemistry), Brown University, 2027

Fall 2024 SPRINT|UTRA Award

Sarah is a second-year undergraduate student interested in environmental chemistry. She is fascinated by how complex systems of chemical reactions are affected by human activity. She works with Sebastian to study how deglaciation changes weathering processes. Outside of that she enjoys traditional Korean drumming, hiking, gardening, and disability justice activism.

Former Group Members

Postdocs

Dr. Natasha Sekhon (Website; IBES Profile) – Voss Postdoctoral Research Associate and Presidential Diversity Postdoctoral Fellow, 2021 to 2023

Current: Assistant Professor at Occidental College!

Dr. Kristina Butler (https://kristinalbutler.com/; https://futurerockdoc.com/) – NSF EAR Postdoctoral Fellow, 2023

Current: Assistant Professor at UT Dallas

Dr. Evan Ramos (Website) – NSF EAR Postdoctoral Fellow, 2021 to 2023; Affiliated Postdoc 2023-2024 (Primarily at Rice University)

Current: Assistant Professor at University of Pittsburgh

Graduate Students

Theodore (Ted) Bobik – Sc.M. Earth, Environmental & Planetary Sciences, Brown University, 2024

Thesis: Filling in the Gaps: Paleosols as Regional Recorders of Hydroclimatic Change in Northeast China at the Cretaceous – Paleogene

Undergraduates

Jesse Miller, A.B. with Honors, Geological Sciences, Brown University, 2023

Summer 2022 SPRINT|UTRA Award and Research at Brown Grant

2023 GSA NE-SE Regional Meeting Presentation: Temperature Dependent Dissolution Experiments of Basalt, Dacite and Pumice from The Little Deschutes River Valley

Senior thesis: Temperature dependent dissolution experiments of basaltic andesite, dacite and pumice from the Little Deschutes River Valley, Oregon

Remote Lab Technician 2023-2024; Manuscript Forthcoming!

Current: Farm Manager, The Opportunity Hub

Alejandra (Ale) Torres, B.S. Candidate Earth Science and Data Science, Southern Methodist University 2026

Summer 2024 Leadership Alliance/DEEPS REU

Upcoming AGU 2024 Poster Presentation!

Tee Gotsch, A.B. Candidate Geology-Biology and Music, Brown University, 2026

Summer 2024 SPRINT|UTRA Award

Jonah Bernstein-Schalet, Sc.B. Candidate Geology-Biology, Brown University, 2024.

2023-24 Voss Undergraduate Fellowship Award

AGU 2023 Fall Meeting Presentation: Linking Post-Wildfire Soil Geochemistry to Carbon Processes and Chemical Weathering

GSA NE 2024 Presentation: Wildfire impacts on soil chemistry and the role of pyrogenic carbon in soil mineral transformation

Senior Thesis: Linking Stream Chemistry to Soil Biogeochemistry to Investigate the Environmental Legacy of Wildfire in Oregon’s West Cascades

Current: Research Scientist, Mati Carbon

Whitney Vieira Ribeiro, Sc.B. Geology-Biology, Brown University, 2024.

Senior thesis: Tracking the Impact of the K/Pg on Pelagic Shark Diversity Using Dermal Denticles

Current: Paleontological Research Institution

Marina Benson, Sc.B. with Honors, Geology-Biology and B.A. Music, Brown, 2024

2023-24 Voss Undergraduate Research Fellow

Senior thesis: Edgartown Great Pond is Turning Green! The Ecological Impacts of Nitrogen Pollution on Coastal Estuaries

Daniel Graves, Sc.B. with Honors, Environmental Sciences, Brown University, 2024

GSA NE Presentation: Variability of groundwater recharge in variable climates: a groundwater flow model for the Southern Great Basin

Senior thesis: Variability of groundwater recharge in variable climates: a water-energy balance groundwater model for the arid Southern Great Basin

Shaw Miller, Sc.B. with Honors, Geology-Biology, Brown University, 2023.5