Research
Drug Counterfeits
Up to 10% of all drugs are counterfeit and this number increases every year. Drug counterfeits are fake drugs intentionally produced with a commercial outcome. Drug counterfeits are a global problem that yearly causes thousands of deaths due to substitution of the active drug compound(s), limited drug production control, and reduced or no pharmaceutical effect of the counterfeited drugs. Non-visual drug counterfeits (e.g. changes in chemical formula or composition) are particularly challenging to identify due to the lack of chemical methods. The components and the drug production method leave a unique and specific chemical fingerprint. Combining knowledge and methods from biogeochemistry to establish a new pharmaceutical methodology can help identify and understand non-visual drug counterfeits through isotopic ratio and trace elemental analysis.
Triple oxygen isotopic systematics of meteoric hydrothermal systems and implications for paleoaltimetry
We are using the triple isotopes of oxygen of hydrothermally altered rocks to determine the isotope composition of meteoric waters that interacted with the crystalline core of mountain belts.
Hydroclimate of the warm Pliocene of western United States
The Pliocene represents a time of elevated carbon dioxide concentrations and a warm climate. We are studying terrestrial climate records of the Pliocene in western United States with the expressed purpose of understanding how western North America will respond to increased CO2 concentrations and a warming world in the future. Our research suggests a wetter southwestern US during warm periods.
Neogene grassland expansion and climatic evolution
Our group works on the hydroclimate that drove grassland expansion in the Cenozoic.
Terrestrial climate of the Cretaceous “hot-house” from the Songliao Basin, northeast China
Because of the need to understand the links and feedbacks of the carbon cycle during times of global greenhouse we are examining the Cretaceous climate record preserved in lake sediments in northern China. The Songliao Basin represents one of the most complete records of terrestrial lake sediments of the Cretaceous and is the target of a massive deep drilling project.
Reconstructing Central Asian climate during the Cenozoic
We are working to understand the interplay between tectonics and 60 million years of climate change on our planet's largest continent. Our field work has focused on the basins north and east of Tibet in China, Mongolia and eastern Kazakhstan. Our current research is now aimed at understanding the early Paleogene climate and tectonic history of the southern margin of Tibet.
The Cenozoic climate record of Western North America
We are developing long-term climate records from the stable isotopes of paleosols, paleolake sediments, and weathered ashes in an effort to understand how climate and tectonics are linked in the North America Cordillera.
Global Compilation of Cenozoic Terrestrial Isotopic Records
We have compiled stable isotope data of Cenozoic terrestrial records taken from over 200 publications. This compilation is given in PATCH Lab (Paleo-Analysis of Terrestrial Climate and Hydrology) (see Kukla et al., 2022, American Journal of Science). The PATCH Lab portal includes 27009 stable isotope measurements from multiple terrestrial proxies. Moreover, these data can be linked to quantitative models for interpreting water isotope and soil carbonate data.