Geochemistry and Isotope Geology

Research at the Geochemistry and Isotope Geology Department

Banner Research

Our research interests span from the formation of the Solar System to investigating the geological processes that occurred over the history of the Earth to studying the interaction between geo-, bio- and atmosphere. To achieve this we develop and apply dedicated sets of novel and established of isotope systems.

Early Earth geological processes

Understanding the physical and chemical processes that operated on the early Earth provides the basic framework for all planetary formation and evolution models. Yet, widespread tectonic processes over geological timescales have destroyed any remnants of early terrestrial crust. This makes the investigation of early Earth processes a daunting task flawed by large uncertainties. To circumvent these problems, we apply a series of novel and sophisticated isotope systems as well as high-precision trace element data in Archean (over 2.5 billion years old!) samples to investigate the geological processes that shaped the young Earth.

R_EarlyEarth

Chemical structure of the Earth´s mantle

The unique chemical and isotopic heterogeneity of the Earth´s mantle is the result of continued crustal recycling at convergent plate margins over billions of years. Identifying the type and chemical composition of recycled components is therefore crucial to our understanding of the structure and geodynamical evolution of the mantle. We employ a series of high-precision chemical and isotopic tracers, such as radiogenic Sr, Nd, Hf, and Pb isotope, stable Mo, and trace element data. By this we characterise the chemical and isotopic inventory of different mantle components and draw conclusions about their origin.

R_Earth-Mantle

Development of geoanalytical methods

Recent technical improvements in mass spectrometric techniques have open up multiple opportunities to follow new research directions in Earth and Planetary Sciences. Over the decade, we have been at the forefront of conceiving, testing and implementing new geoanalytical methods. Such customised and fit-for-purpose applications allow us to take full advantage of these new developments and to tackle these new questions (Prof. Matthias Willbold).

R_Geoanalytical

Speleothem-based palaeoclimate research

Speleothems are archives for palaeoclimate proxies and are dateable at very high precision back to approximately 600 ka BP using the U-Th technique. Changes of the speleothem growth rates are often related to changes in precipitation intensity, temperature or vegetation cover above the cave. Multiproxy studies on stalagmites, involving combinations of U-Th dating, stable isotopes and trace elements have enormous potential for palaeoenvironmental studies. Our work is currently focussed on speleothems from Northern Africa and the Iberian Peninsula (Dr. Dirk Hoffmann).

R_Speleothem

Sampling of tropospheric CO2

To trace the origin of atmospheric CO2, we have developed one of the few laboratories worldwide that specialize in analyzing the rare isotope 17O in atmospheric CO2.

Isotope analyses and mass spectrometry

Noble gas mass spectrometry allows the dating of geological processes on the basis of the abundance of the 40-Ar isotope.
We use the ratios of stable oxygen, carbon and silicon isotopes to solve problems in the fields of geo- and cosmochemistry, but also atmospheric sciences. Notably that measurement of the abundance of the rare isotope 17-O opens a new and innovative field in stable isotope research.

Geo- and cosmochemistry

We use aerodynamic levitation melting and LA-ICPMS for high-precision analyses of element ratios (e.g., Y/Ho, Zr/Hf, REE). Using elementa ratios, we want to study processes that have occurred during the formation of the fist solids in the Solar System by condensation from the gas phase (Prof. Andreas Pack).