【IC-DLI Webinar】From the winners of "Deep Life Paper” and "SiYuan-Ocean Emerging Leader" Awards in 2025

2026 IC-DLI Webinar I 

Time： 29th October 13:00(UTC) 21:00(Beijing)

ZOOM ID：868 9743 2578

Passcode：467439

ZOOM link：https://us06web.zoom.us/j/86897432578?pwd=Yk0vXd4SrbOc5blow2Lr0XGN6VLHO5.1

Speaker：Dr. Xiao Wu, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences

Title：Crustal Faulting Drives Iron Redox Cycling and Sustains the Deep Biosphere

Abstract：Crustal faulting cleaves Si–O bonds on fresh rock surfaces, generating mineral radicals that split water into reactive redox pairs, such as H₂ and H₂O₂. Rock fracturing in extension fractures builds robust redox gradients, whereas generate H₂ without H₂O₂ accumulation in shear fractures. In addition, the oxidants oxidize Fe²⁺ only marginally, while •H efficiently reduces Fe³⁺ back to Fe²⁺. Earthquake-induced faulting produces extremely high local fluxes, orders of magnitude above the needs of lithoautotrophic microbial ecosystems, and establishes redox potentials (–0.41 to +0.82 V) that drive Fe, C, N and S cycling and support diverse metabolic activities in the deep biosphere.

Speaker：Dr. Shuchai Gan, South China Botanical Garden, Chinese Academy of Sciences

Title: Unlocking Deeply Buried Organic Carbon: Biotic and Abiotic DOM Transformations in Deep Subseafloor

Abstract：Deep-sea sediments store vast ancient carbon, but the mechanisms supplying bioavailable substrates to the deep biosphere remain poorly understood. Using 7.8-million-year-old sediments from the Nankai Trough, we simulated burial temperatures (20–85°C) in 55-day incubations. By combining 3D fluorescence spectroscopy and ultrahigh-resolution mass spectrometry, we demonstrate that moderate heating triggers abiotic processes. Above 55°C, thermal energy breaks down refractory nitrogenous humic substances, releasing smaller, highly bioavailable dissolved organic matter (DOM) and generating labile H₂ and acetate. This thermally driven mechanism reverses both mineral and microbial carbon pumps, unlocking hidden energy for deep-seafloor microbial life.

Adward Presenter:  Prof. Kai-Uwe Hinrichs, University of Bremen

                 Prof. Karen G. Lloyd, University of Southern California