Guohui Gao

Doctoral / Post-doctoral researcher

THESIS SUBJECT

Reconstruction of past hydrological changes of deep- and intermediate-water masses of the central Mediterranean Sea during the last climatic cycle (last 145 kyr) from geochemistry investigation of foraminifera.

THESIS SUMMARY

Variations in Mediterranean thermohaline circulation during the last climatic cycle and their role on sapropel depositions are poorly understood, although it is believed that they had a significant influence on the Atlantic Meridional Overturning Circulation (AMOC) over this time period.

Paleo-hydrological processes and associated ventilation dynamics related to sapropel deposition (characterized by >1% Corg) are still debated because  continuous δ13C and δ18O records of epibenthic foraminifera are scarce for the last glacial / interglacial climatic cycle due to the lack of epibenthic foraminifer species with calibrated vital effect for δ13C analyses during bottom suboxic or anoxic events (e.g. sapropel events and ORLs). Here, we have investigated εNd on planktonic foraminifera to reconstruct past hydrological changes of the intermediate- and deep-water masses of the central Mediterranean Sea for the last 145 kyr. New benthic foraminiferal geochemical proxies will be also explored to reconstruct past changes of water masses conditions.

SUPERVISORS

Thesis supervisor : Christophe Colin (GEOPS, Université Paris-Saclay, France)

Thesis co-supervisor : Sophie Sepulcre (GEOPS, University Paris-Saclay)

FUNDING

International Doctoral Scholarship (CSC, Chine)