Canadian Arctic 2017 Expedition
August 30-September 12, 2017
A group of MBARI scientists and engineers, led by geologist Charlie Paull, is returning to the Canadian Beaufort Sea on the Korean icebreaker R/V Araon. They will conduct targeted surveys and sampling here to explore seafloor features unique to the Arctic continental margin. This work is in collaboration with researchers from the Korean Polar Research Institute (KOPRI) and the Geological Survey of Canada (GSC).
Young Kuen Jin of the Korean Polar Research Institute is serving as chief scientist of this expedition and will be coordinating the entire expedition. His team has a particular focus on the collection of geophysical data to determine the distribution of sub-seafloor permafrost. The Araon will also be carrying teams from KOPRI skilled in multi-beam, sediment core, and water column data collection. The KOPRI team also includes microbiologists who will be especially interested in sampling around methane venting sites.
The continuing possibility of exploratory hydrocarbon drilling on the outer shelf and slope of the Beaufort Sea has created a pressing need to characterize offshore geological hazards and identify sensitive marine habitat. The GSC team is undertaking a regional appraisal of the area, which includes investigation of the distribution and geotechnical properties of shallow surface sediments, the activity of sea-bed processes, and the quantification of hazardous geologic environments.
Recent exploration in the Canadian Beaufort Sea has revealed a remarkable coalescence of seafloor morphologic features (pingos, pockmarks, large slide scars, mud volcanoes, and massive glacial-marine deposits) at the continental shelf edge and on the continental slope. Widespread methane and freshwater venting as well as gas hydrate deposits have been discovered and are of particular interest. This expedition will be focused on investigating permafrost and gas hydrate distribution under the shelf and slope as well as making detailed investigations of morphologic features near the shelf-slope transition.
In previous research cruises (in 2003, 2010, 2012, 2013, 2016) in the Canadian Beaufort Sea, MBARI and GSC have documented the existence of methane gas release from several sites on the continental shelf and slope. Most of the venting methane gas is believed to be derived from the decomposition of permafrost or gas hydrate deposits that exist underneath the arctic continental shelf.
Past surveys have also revealed the existence of an unusual concentration of distinct morphologic features, including scars of large submarine landslides, isolated topographic mounds including some associated with fluidized mud deposits, known as mud volcanoes, and the existence of glacially derived marine deposits. All these features are potential marine geohazards. The impact of submarine permafrost formation and/or degradation on the formation of these seafloor structures remains poorly understood. However, the earlier discoveries have already substantially advanced our understanding past glacial extents as well as the process that may be modifying the shape of the Arctic seafloor now.
Paull and the MBARI team will be bringing scientists, engineers, and scientific equipment to the Arctic as part of a larger effort to explore the geology of this remote area. The autonomous underwater vehicle (AUV) will conduct detailed mapping surveys of areas distinguished by anomalously rough morphology that may indicate unstable seafloor, potentially associated with gas venting and the freezing or thawing of seafloor sediments. They will also remap seafloor areas that are active enough to have experienced measurable changes in morphology between the 2013 and 2016 surveys with the goal of quantifying the seafloor changes that may be occurring in these dynamic areas. Next, MBARI’s Mini remotely operated vehicle (MiniROV) will visit those mapped areas so the scientists can actually see the mapped features. The MiniROV will also record video data, collect sediment cores, gas samples, and water column measurements. All this data will be studied and analyzed to garner a better understanding of the complex processes occurring here on the Arctic continental shelf and slope.
Check back for updates.