Title: Harry H. Hess Postdoctoral Research Fellow

Position: Research Staff

Area(s): Geology

Research summary:   Mebrahtu Weldeghebriel is broadly interested in ancient-ocean chemistry, paleoclimatology, and low-temperature geochemistry of chemical sediments, particularly evaporites. His research focuses on:

1. Documenting the major, minor, trace element, and isotopic composition of ancient seawater using direct measurements of “fluid inclusions” (tiny samples of ancient seawater) trapped in marine halite.
2. Understanding of what controls long-term changes in the elemental and isotopic composition of seawater on multimillion-year timescales using mass balance modeling, and
3. Linking changes in the chemistry of ancient seawater to climate and atmospheric CO₂, and the biological evolution of marine shell-building organisms.

Other focus involves sedimentological and geochemical characterization of recent evaporite sequences in Dead Sea as a modern analog to deep hypersaline basins in the geological record.

Keywords: fluid inclusions, halite, seawater chemistry, climate