Marine geology & Biogeochemistry Lab.

Dr. Yang specializes in microbe-mineral interaction in seafloor Fe-Mn deposits, hydrothermal alteration in deep subseafloor sediment and basalt, smectite-illite transformation in accretionary prism subduction zones, and nanoscale-transition metal oxidation states alteration process by using Transmission Electron Microscopy-Electron Energy Loss Spectroscopy: TEM-EELS. Recently Dr. Yang studied the effects and a mechanism of microbial interaction in deep sea ferromanganese crusts. He focused on the nanoscale Fe-oxidation states changes of Fe-bearing vernadite mineral. He discovered the Fe-oxidation states of vernadite mineral changes in each layer of ferromanganese crust, indicating that redox condition of surrounding paleoenvironment of seawater were recorded in layers of ferromanganese crust as well as manganese utilizing microbes play a significant role in promoting the manganese oxide precipitation. These results allowed us to determine the contribution of microbial activities as well as the reconstruction of paleoenvironments through nanoscale mineral analysis using cutting edge technic of TEM-EELS. The papers for these findings were published in “Marine geology” (April 2019) and “Geochemistry, Geophysics, Geosystems” (Feburary 2023). He has also performed extensive research on the International Ocean Discovery Program (IODP) deep subseafloor sediments from Nankai trough, South Pacific Gyre and South Atlantic Transesct. Dr. Yang also has worked integrated study of the microbes-clay mineral interaction and structural changes of bioreduced Fe-rich smectite. He joined several times of IODP expeditions (329, 348, 370 and 390) as a mineralogy & sedimentology specialist, focused on the biogenic smectite-illite transformation that could trigger deep sea fault events. A list of selected Dr. Yang’s activities are as follows.