Date: 16.00-18.00, Friday, 17 November 2017
Place: 3F, Lecture room, Main Chemistry Build.
Speaker： Li Yuan
Earth’s nitrogen evolution: Insights from high-pressure experiments
Nitrogen is an element that can be used to constrain the evolution and interaction of Earth’s different reservoirs. Moreover, nitrogen in the form of NH3 was an important ingredient for the abiotic synthesis of biomolecules, and may also have played an important role in modulating the climate on the early Earth. N2 is the main component of Earth’s present atmosphere, but the Earth’s deep nitrogen geochemistry is rarely known. Traditionally, nitrogen was thought to be a highly incompatible element, and the Earth’s interior may hold very little nitrogen. However, recent studies show that a significant amount of nitrogen may have been stored in the Earth’s silicate mantle and metallic core. In this talk, I will review the geochemical behavior of nitrogen during Earth’s core-mantle segregation, the dissolution of nitrogen in Earth’s mantle minerals, the speciation of nitrogen in Earth’s fluids, and the partitioning of nitrogen during shallow magma degassing. I finally give a general picture