Global glaciation: Increases volcanism along mid ocean ridges

New research highlights the connection between global glaciation events and increased volcanic activity along mid-ocean ridges (MORs). These underwater mountain ranges play a crucial role in transferring heat, metals, and carbon from the Earth's interior to the deep ocean, thereby influencing the movement of chemical elements between the Earth's living and nonliving components, including the atmosphere, water, and soil.

Professor Sunil Kumar Singh, Director of the CSIR-National Institute of Oceanography (NIO) in Goa, India, explained that his team's research establishes a clear link between glaciation and volcanism. "Increased volcanism along the hydrothermal ridges during the glacial period increased the hydrothermal activity that further increased carbon dioxide flux," he stated.

The study, conducted by Singh along with CSIR-NIO researchers Sayantan De and Robin John, involved analyzing a 49,000-year sediment record obtained from the Carlsberg Ridge (CR) in the Indian Ocean. Their investigation sought to understand the relationships between glacial-interglacial sea-level changes, volcanism, and hydrothermal activity.

According to Singh, the team reconstructed hydrothermal variability by analyzing trace elements and lead (Pb) isotopes found in Ferro-Manganese (Fe–Mn) oxyhydroxide coatings from sediment cores. "The study presents the first lead (Pb) isotope record of Fe–Mn coatings from an active mid-ocean ridge in the Indian Ocean, offering new insights into how sea-level modulates hydrothermal regimes at slow-spreading ridges over millennial timescales," he said. He further noted that the geochemical diversity of deep-sea sediments along MORs is influenced by hydrothermal materials and fluids, volcanic fragments, and lithogenic debris.