The southwestern Barents Sea margin has attracted growing interest due to its hydrocarbon potential. However, the dynamics of its shallow subsurface fluid systems remain poorly understood. This thesis investigates fluid migration, faulting, and shallow gas accumulations within the southern Sørvestsnaget Basin adjacent to the Senja Ridge, using high-quality 3D seismic data (Carlsen3D) in combination ...

The southwestern Barents Sea encompasses a large part of the Norwegian Continental Shelf (NCS), expressing a complex geological history. The area is characterized by a series of rifting episodes from the Mesozoic and Paleozoic eras, along with more recent glacial impacts from the Late Cenozoic and the Quaternary period. The SW Barents Sea has experienced erosion and uplift, with large depocenters ...

Carbon cycling between surface and mantle reservoirs is pivotal in fostering habitability of Earth. A critical yet poorly constrained parameter is whether crustal carbon can “survive” devolatilization processes that accompany slab subduction and therefore influence deep carbon budgets. Carbonatites provide a key record to address this important topic. Here, we present high-precision potassium isotope ...

Planktic foraminifers, pteropods, and coccolithophores are marine calcifiers, organisms living in the water column and found throughout all oceans, with shells made of calcium carbonate. Because of their shell, they play an important role in the carbon cycle exporting calcium carbonate from the upper ocean to the sea floor when they die and sink. If no dissolution occurs on the water column or within ...

Slow–ultraslow spreading ridges represent half of the total length of the global mid-ocean ridge system and have been recognized to host hydrothermal activity. Their role as a source versus sink of elements in the oceans remains poorly constrained. Here, we present the first sediment data from the Aurora Vent Field (~3900 m depth) on the ultraslow spreading Gakkel mid-ocean ridge and the northernmost ...

The particulate organic carbon (POC) flux from the euphotic zone to the deep ocean is central to the biological carbon pump. It is typically evaluated using “export efficiency” and “transfer efficiency,” which reflect POC formation and sinking and carbon sequestration efficiency in the ocean's interior, respectively. Since observations of these metrics are limited, biogeochemical models can elucidate ...

The Arctic cryosphere is the epicentre of acute global change impact, with abrupt warming and amplification driving rapid sea ice decline and irreversible glacial ice loss. A key challenge is understanding how the cryosphere meltdown will impact Arctic marine carbon cycles and ecosystems. Here, we use organic geochemical biomarkers to trace the contribution of different planktonic groups to organic ...

While climate change is of global concern, its impacts are especially rapid and pronounced in Arctic ecosystems. Arctic glaciers have been particularly impacted, with increasing melt and retreat in conjunction with shifts in riverine freshwater and sediment discharge. Arctic fjords are the ultimate recipients of glacial discharge and a plethora of heavy metals released from glacial environments. ...

The polar regions are biologically productive and play a critical role in regional and global biogeochemical cycling. A key nutrient is dissolved silicon, required for the growth of siliceous phytoplankton, diatoms, which form an important component of polar ecosystems. Glacial weathering is thought to be an important dissolved silicon source to coastal waters, especially critical in regions ...

Arctic marine systems are vital to the Earth’s ecological and climatic balance and harbour a unique biodiversity adapted to extreme conditions. However, they are under unprecedented threat from climate change, in particular from “Atlantification”, i.e., the loss of sea ice and the increasing influence of Atlantic Water (AW) in this region. Long-term observatories are crucial to detect even small ...