Degassing processes at the bottom of the Atlantic ocean

The article presents an overview of degassing processes and their traces based on the results of long-term observations and analytical studies by the author while working on the research vessel “Professor Logachev”. On it, the Polar Marine Geological Exploration Expedition conducts research, including video observations in the axial zone of the Mid-Atlantic Ridge (MAR). Since 2012, work has been conducted within the Russian Exploration Area (REA), located on the Mid-Atlantic Ridge at coordinates from 20° to 13° N. During this time, several thousand linear kilometers of bottom video were filmed. The author of this review took part in eighteen such cruises, so she had the chance to directly observe various signs of degassing processes on the ocean floor. They are manifested in the form of small (rarely exceeding the first meters in diameter) channels in sediments and unusual patterns on sediments, as well as cracks, faults and channels in the underlying rocks. In addition, all hydrothermal structures, including chimneys of active and inactive smokers, are also the result of degassing processes. Within the young volcanic structures, both caldera and slot types, sintered sediments were raised, saturated with ash and fresh volcanic glass (the size of glass fragments rarely exceeds 1 cm). Such rocks are classified as tuffites, and its formation is also related to the degassing processes.