Photo of Dr Clemens Vinzenz Ullmann

Dr Clemens Vinzenz Ullmann

Research Fellow


My research concentrates on the geochemistry of macrofossil calcite. The three main topics I am working on are carbonate diagenesis, vital effects related to the process of bio-mineralization and reconstruction of past environments using isotopic and element tracers. I have been involved in work from the Mesoproterozoic up to modern times, but my main focus has been the Jurassic.

I am mostly working with GS-IRMS (C and O isotopes); ICP-OES; ICP-MS (Mg/Ca, Sr/Ca, Fe/Ca, Mn/Ca) and SEM (calcite ultrastructure), but also use TIMS (87Sr/86Sr), MC-ICP-MS (Li isotopes) and SIMS (S, C, O isotopes).

I am currently Researcher Co-I on the NERC and ICDP funded JET project (Integrated Understanding of the Early Jurassic Earth System and Timescale).


Previous work and education

10/2014-09/2016                        Leopoldina Fellow; University of Exeter, UK. Research on biomineralization of brachiopods, barnacles and belemnites. Funded by the Leopoldina - German National Academy of Sciences.

10/2013-09/2014                        Post Doc; University of Copenhagen, Denmark. Research on geochemical proxies in biogenic carbonates. Funded through a grant to R. Frei.

03/2012-08/2012                        Academic visitor; University of Oxford, UK. Lithium isotopes in belemnite calcite and chemostratigraphy of the Jurassic. Hosted by S.P. Hesselbo and P.A.E. Pogge von Strandmann.

10/2010-09/2013                        PhD; University of Copenhagen, Denmark. ”Isotopic and elemental proxies in mollusc and brachiopod calcite: diagenesis, vital effects and climatic trends”. Funded through FNU grant to C. Korte.

10/2008-09/2010                        MSc; Freie Universität Berlin, Germany. ”Mg isotopes in the rivers Danube, Elbe and Rhine: Implications for weathering an carbon budget”. Supervised by U.H. Wiechert, H.J. Becker and R.L. Romer.

10/2005-09/2008                        BSc; Freie Universität Berlin, Germany. ”oxygen isotope variations in the Giant Pacific Oyster (Crassostrea gigas)”. Supervised by C. Korte and U.H. Wiechert.