My research focuses on foraminifera, a group of single-cell eukaryotic organisms, which enables me to pursue a wide range of research topics in the fields of paleoceanography, Earth's climate, biogeochemical cycles, and molecular biology.
In addition to the application of traditional tools (e.g. benthic foraminiferal carbon and oxygen isotopic ratios) to the investigation of ocean circulation changes in the geological past, I am interested in the development of novel geochemical proxies to tackle fundamental paleoceanographic and paleoclimatic questions. Currently, I am working on the development of new proxies to reconstruct: 1) methane fluxes in sedimentary environments today and in the geological past; 2) modern and past changes in the carbon, sulfur, manganese, and iron cycles as consequences of methane release and oxidation and availability of oxygen in sediments. In order to do so, I am exploring the possibility of using: 1) "non-traditional" isotopic ratios in benthic foraminifera to study methane fluxes in marine sediments; and 2) a multi-proxy approach, involving the benthic foraminiferal carbon isotope and element/Ca ratios to investigate changes in biogeochemical cycles in sediments.
Because of my background in marine biology, I am also very interested in the genetics of foraminifera. Currently, I am exploring the molecular heterogeneity of the foraminiferal genus Bolivina small subunit ribosomal DNA in the context of the application of DNA barcodes to the identification of foraminiferal species in environmental samples.
- S.J. Langton, N. M. Rabideaux, C. Borrelli, and M.E. Katz (2016), Southeastern Atlantic deepwater evolution during the late middle Eocene to earliest Oligocene (ODP Site 1263 and DSDP Site 366), accepted for publication in Geosphere.
- C. Borrelli and M.E. Katz (2015), Dynamic deep-water circulation in the northwestern Pacific during the Eocene: Evidence from Ocean Drilling Program Site 884 benthic foraminiferal stable isotopes (δ18O and δ13C), Geosphere, 11(4), 1204-1255, doi:10.1130/GESO 1152.1.
- C. Borrelli, B.S. Cramer, and M.E. Katz (2014), Bipolar Atlantic deepwater circulation in the middle-late Eocene: Effects of Southern Ocean gateway openings, Paleoceanography, 29(4), 308-327, doi:10.1002/2012PA002444.
- C. Borrelli, A. Sabbatini, G.M. Luna, M.P. Nardelli, T. Sbaffi, C. Morigi, R. Danovaro, and A. Negri (2011), Technical Note: Determination of the metabolically active fraction of benthic foraminifera by means of Fluorescent in Situ Hybridization (FISH), Biogensciences, 8, 2075-2088, doi:10.5194/bg-8-2075-2011.