| Titre | The 2016 Canada-Sweden Polar Expedition: initial results of seismic reflection and refraction experiments over the Lomonosov Ridge and Marvin Spur |
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| Auteur | Funck, T; Shimeld, J; Hopper, J R; Chian, D |
| Source | 19th EGU General Assembly, EGU2017, proceedings from the conference held 23-28 April, 2017 in Vienna, Austria; 2017 p. 6057  Accès ouvert |
| Liens | Online - En ligne
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| Image |  |
| Année | 2017 |
| Séries alt. | Secteur des sciences de la Terre, Contribution externe 20160310 |
| Réunion | EGU2017, 19th European Geosciences Union General Assembly; Vienna; AT; avril 23-28, 2017 |
| Document | livre |
| Lang. | anglais |
| Media | en ligne; numérique |
| Formats | html |
| Programme | Délimitation du plateau continental du Canada en vertu de la Convention des Nations Unies sur le droit de la mer (UNCLOS) |
| Diffusé | 2017 04 01 |
| Résumé | (disponible en anglais seulement)
In August and September 2016, Canada and Sweden collaborated in a scientific expedition to the Arctic Ocean utilizing two polar class icebreakers: the Swedish
Oden and the Canadian Coast Guard Ship Louis S. St-Laurent. Each ship was equipped with comparable systems for collecting seismic reflection and refraction data, giving a high degree of operational flexibility and spare equipment capacity in the
field. A total of three helicopters supported the deployment and recovery of sonobuoys and on-ice seismometer stations (equipped with two hydrophones and a vertical geophone) along the seismic lines.
A principal scientific objective is to improve
understanding of the tectonic evolution of the Arctic Ocean, which will ultimately help to define the Extended Continental Shelf of Canada. A key region to further this objective lies between the Lomonosov and Alpha ridges. The expedition collected a
continuous seismic profile running from the Amundsen Basin, across the Lomonosov Ridge and sub-parallel Marvin Spur, through the Makarov Basin and onto the central Alpha Ridge. A second profile of the Lomonosov Ridge was acquired, and a cross-line
joining the two was also run along much of the Marvin Spur. The combined length of these reflection and refraction lines is 1037 km. A total of 33 sonobuoys and five on-ice seismometer stations were used successfully to record the airgun shots
(source volume between 1150 and 2000 cubic inches), which were fired at a maximum interval of 20 seconds.
The data will provide information on the continent-ocean transition zone at the Eurasian flank of the Lomonosov Ridge between Chron C24 and
the more controversially discussed Chron C25. Is C25 a true seafloor spreading anomaly or is the anomaly related to serpentinization processes? A dense receiver spacing of 15 km and reversed observations will provide details on the crustal structure
of Marvin Spur and will show how much the spur was affected by magmatism associated with the High Arctic Large Igneous Province. Similarly, the data between the Lomonosov and Alpha ridges will show how these structures are connected. In particular,
the results will elucidate the temporal and spatial relationship of the formation of Alpha Ridge and the Makarov Basin.
Crustal scale P-wave velocity models will be developed along the transects. Coincident seismic reflection as well as gravity
data will provide additional constraints on the models. Initial results of the forward modeling of observed travel times will be presented. |
| Sommaire | (Résumé en langage clair et simple, non publié)
En août et septembre 2016, le Canada et la Suède ont collaboré à une expédition scientifique dans l'océan Arctique à l'aide de deux brise-glaces
de classe polaire: le Swedish Oden et le navire de la Garde côtière canadienne Louis S. St-Laurent. Chaque navire était équipé de systèmes comparables pour recueillir des données sismiques de réflexion et de réfraction. Le principal objectif
scientifique est d'améliorer la compréhension de l'évolution tectonique de l'océan Arctique, ce qui aidera finalement à définir le plateau continental étendu du Canada. Un domaine d'intérêt important était la région entre les crêtes de Lomonosov et
Alpha. Les données sismiques recueillies au cours de cette expédition fourniront des informations sur les types de croûtes et la nature des transitions entre le bassin Amundsen, la crête de Lomonosov et Alpha Ridge. |
| GEOSCAN ID | 299627 |
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