The deep Arctic Ocean is not known for its wildlife. 1200 metres from the surface, well beyond where light penetrates the water and at temperatures below zero, it it’s a desolate, hostile environment. There are, however, exceptions to this, most notably around seeps in the seafloor that leak methane into the water above. On the Vestnesa Ridge, just off Svalbard, great plumes of methane stretch some 800 metres above the seabed. These seeps occur within pockmarks, depressions in the sea’s soft sediment, which span hundreds of metres across. At their base lies carbonate reefs, wide microbial mats and thriving meadows of tubeworms, which stretch out into the current. The microbes turn the methane into something much more valuable – carbon, and form the base of the deep Arctic food chain. Emmelie Åström, a PhD student from the Centre for Arctic Gas Hydrate, Environment and Climate, has been using high definition seafloor images to work out what effect these seeps have on the surrounding biota. The images reveal that the carbonate rocks that form at the seep’s margins create a unique habitat in an otherwise featureless environment. These structures provide shelter for a huge variety of animals, which benefit from a food chain fuelled by methane. She presented her results at the EGU General Assembly this week.
GeoLog | Methane seeps – oases in the deep Arctic Ocean.
Source: GeoLog | Methane seeps – oases in the deep Arctic Ocean