Venting induced by magma-sediment interaction at Jøtul field – first discovery of hydrothermal seafloor venting along the 500-km-long Knipovich spreading ridge ...

• Main Authors: Bohrmann, Gerhard, Streuff, Katharina, Römer, Miriam, Knutsen, Stig-Morton, Smrzka, Daniel, Kleint, Jan, Röhler, Aaron, Pape, Thomas, Sandstå, Nils Rune, Kleint, Charlotte, Hansen, Christian, Bach, Wolfgang
• Format: Text
• Language: English
• Published: Deutsche Geologische Gesellschaft - Geologische Vereinigung e.V. (DGGV) 2023
• Subjects: Knipovich Ridge; Svalbard
• Online Access: https://dx.doi.org/10.48380/7x8p-x298; https://www.dggv.de/e-publikationen/venting-induced-by-magma-sediment-interaction-at-jotul-field-first-discovery-of-hydrothermal-seafloor-venting-along-the-500-km-long-knipovich-spreading-ridge

During expedition MSM109 in July 2022, a new hydrothermal vent field was discovered, which is the first active field found along the 500-km-long ultra-slow spreading Knipovich Ridge. The so-called Jøtul hydrothermal field is not located on an axial volcanic ridge (AVR) but is associated with the eastern bounding fault of the rift valley. A hydrothermal plume with methane concentrations between 100-1000 nmol/L emits hot fluids into the water column above the hydrothermal field, and is being drifted north with the bottom current. These high methane emissions are likely related to interactions between magmatic intrusions and sediments of the Svalbard continental slope produce unusually high release of thermogenic methane. Further investigations during MSM109 using ROV Quest show a wide variety of fluid escape sites such as diffusive venting from sediments, as well as seepage from joints and cracks within igneous rocks. Additionally, new inactive and active mounds with abundant hydrothermal precipitates and ...