Methane gas and methane ice (methane hydrates) are common on continental shelves worldwide. In Malin Waage`s PhD thesis entitled “3D and 4D seismic investigations of fluid flow and gas hydrate systems – at sites across the Barents Sea and NW Svalbard margin,” she investigates the sources and mechanisms leading to methane flow beneath the seabed and its release into the water.
The sediments and sedimentary rocks of the Barents Sea are examined using high-resolution 3D seismic data. The seismic system provides promising results for detailed investigations of the dynamic nature of natural methane release sites. Moreover, the work involves introducing and testing a new method for monitoring methane migration below the seafloor – 4D seismic imaging. The method is based on acquiring identical 3D seismic data sets, repeated over time-span of 1-2 years.
The study shows that the two methane release locations lie over shallow petroleum reservoirs. Tectonic faults assist in methane migration from the deep, connecting these reservoirs to the seabed. Some of this methane was previously trapped as gas hydrates that melted some 20,000 – 15,000 years ago under past climate change, and is now making it past the seafloor and into the water.
Waage defended her thesis on February 18th, 2019 at UiT The Arctic University of Norway. Her PhD was funded by VISTA – a basic research collaboration between Equinor and the Academy of Science and Letters and supported by the Centre for Arctic Gas Hydrate, Environment, and Climate (CAGE).
To find out more, read the two academic articles written based on the findings of this research; links found below.
Repeatability of high-resolution 3D seismic data
Geological Controls on Fluid Flow and Gas Hydrate Pingo Development on the Barents Sea Margin
