(Text by ZHANG Fangyi, zhangfy@qdio.ac.cn)
Fangyi was giving a presentation at the EGU (European Geosciences Union) conference. Credit: Institute of Oceanology, Chinese Academy of Sciences
Volcanic activity is closely intertwined with human life. While volcanic eruptions can unleash devastating ash and lava flows that destroy buildings and disrupt the environment, they also have the paradoxical benefit of creating fertile soils that support agriculture. During field investigations of volcanic rock strata in North China, the enigmatic nature of these rocks sparked my deep interest in magmatic processes, fueling a passion to better understand the forces shaping our planet.
Mantle-derived magmatism serves as a bridge between the Earth's deep mantle and the external surface layers. Such magmatic activity can transport volatiles from the deep mantle to the surface, influencing atmospheric composition. In this process, the redox state of the magma plays a key role in determining the nature of volatiles (oxidizing vs. reducing), making the study of magma's redox state crucial to understanding the formation of a habitable Earth.
As a petrologist, my primary focus is on investigating the redox state and volatile composition of oceanic basalts and their influence on atmospheric composition. In the attached image, I am presenting my research at the EGU conference, where I discussed the redox state of the oceanic mantle and its implications for deep mantle melting processes. This study demonstrates that an oxidized oceanic mantle can lead to the formation of carbonate melts in the deep mantle, significantly affecting the deep carbon cycle. Another study of mine reveals that the mantle's redox state has remained unchanged since the Hadean Eon, with the long-term cooling of the mantle causing mantle-derived magmas to gradually become more oxidized, thereby contributing to the increase in atmospheric oxygen levels.
While my current research is ocean-focused, my future work will expand beyond oceanic basalts. I plan to investigate the redox state of arc and continental basalts, which have significant impacts on the surface environment. These studies will help us better understand the causes of mass extinction events and the processes leading to Earth's habitability.
(Editor: ZHANG Yiyi)