Shallow Seafloor Gas emissions Near Heard and McDonald Islands on the Kerguelen Plateau, Southern Indian Ocean

Researchers have uncovered evidence of submarine gas emissions near Heard and McDonald Islands on the Kerguelen Plateau, marking the first documented seafloor bubble production in this remote region. The study, utilizing hydroacoustic flares, deep-tow camera footage, water properties analysis, and isotopic data (δ³He, δ¹³C, δ³⁴S), identified potential sources of methane and CO₂ linked to both shallow diffuse hydrothermal venting near McDonald Islands and deeper-sourced thermogenic methane or sediment-hosted geothermal systems at Heard Island. The findings suggest active carbon cycling processes in the southern Indian Ocean, with implications for understanding seafloor dynamics and volcanic activity on large igneous provinces.

Spain, E. A., Johnson, S. C., Hutton, B., Whittaker, J. M., Lucieer, V., Watson, S. J., Fox, J. M., Lupton, J., Arculus, R., Bradney, A., & Coffin, M. F. (2020). Shallow Seafloor Gas emissions Near Heard and McDonald Islands on the Kerguelen Plateau, Southern Indian Ocean. Earth and Space Science, 7(3). Portico. https://doi.org/10.1029/2019ea000695