Title: "Triple oxygen and hydrogen isotopes of gypsum hydration water: A resurrected proxy of hydrologic change"
Abstract: Many minerals incorporate water directly into their structure as molecular water (H2O) or hydroxyl (OH). The oxygen (16O,17O,18O) and hydrogen (H,D) isotopes of hydrated minerals are a potentially rich source of information about the environmental conditions under which hydrated minerals form and/or interact with fluids after deposition. As part of a 5-year European Research Council project, my group has been developing the use of triple oxygen and hydrogen isotopes of structural water contained in hydrated minerals as a paleoclimate proxy. I will specifically discuss the merits and uncertainties in combining measurements of d18O of biogenic carbonates and triple oxygen and hydrogen isotopes of hydration water in gypsum (CaSO4·H2O) in lake sediments cores to estimate past changes in temperature, rainfall and relative humidity on the Yucatan Peninsula, Mexico.
Short Bio: David Hodell is Woodwardian Professor of Geology at the University of Cambridge and Fellow of Clare College. He is an isotope geochemist and Director of the Godwin Laboratory for Palaeoclimate Research. Prior to relocating to the UK in 2008, he spent over 20 years at the University of Florida in the Department of Geological Sciences. He received his Ph.D. in 1986 in marine geology from the Graduate School of Oceanography, University of Rhode Island. His research utilizes sediment cores collected from lake and ocean bottoms to probe past changes in Earth's climate, oceans, and environment. He is currently engaged in research to understand the past mechanisms responsible for millennial and glacial-interglacial changes in Earth’s climate system during the Quaternary. He also has a longstanding interest in how ancient civilizations affected their environment and, in turn, how environmental and climate change may have influenced cultural change. He is on sabbatical leave at Harvard until 1 June 2019 (Office: Room 433H Museum).