Riiser-Larsen Sea
The Riiser-Larsen Sea is one of the
To the south of this area lies the Princess Astrid Coast and Princess Ragnhild Coast of Queen Maud Land. In the western part is the Lazarev Ice Shelf, and further east are Erskine Iceport and Godel Iceport, and the former Belgian Roi-Baudouin Station.
Name dispute
The Riiser-Larsen Sea was named in 1962 by the
Bathymetry
Depths exceed 3,000 meters in most of the waters here. The area is covered with drifting ice almost year-round. It would stretch over an area of 1,138,000 km².[4] The seafloor of the Riiser-Larsen Sea is relatively flat.[5]
The bedrock in the Riiser-Larsen Sea is one of the oldest around Antarctica (145 Ma) and erosion over this long timespan has produced the largest submarine canyons of the continent. The two dozens canyons in the Riiser-Larsen Sea can be divided into two groups: surface canyons and buried canyons. The buried canyons are twice the size and much older (4–7 Ma) than the surface canyons (younger than 2.4 Ma). The continental shelf of the Riiser-Larsen Sea is relatively narrow and forms rugged terraces at a depth of 750 m (2,460 ft), probably the maximum extent of seafloor-reaching icebergs. The buried canyons formed during a period of maximum glaciation when grounded icebergs reached the shelf edge which resulted in a peak in sediment transport. As the ice sheet had retreated sediments got trapped on the shelf and the sediment supply to the canyons was cut off.[6]
The Riiser-Larsen Sea was one of the first Antarctic marginal basins to be affected by the expanding ice sheet at c. 34 Ma.[7] The oldest, pre-glacial deposit sequence consists of turbidites and hemipelagic sediments. The expanding ice sheet initially triggered slumps and flows of debris that were deposited on the upper continental rise. Because of progradation later deposits ended up on the lower rise and the abyssal plain. Then large channel-levee complexes developed on the upper rise resulting in an unconformity associated with the Middle Miocene intensification of the Antarctic Circumpolar Current.[8]
Opening of Riiser-Larsen Sea
The break-up of
References
Notes
- ^ Leitchenkov et al. 2008, Introduction, pp. 135–136
- ^ "Limits of Oceans and Seas, 3rd (currently in-force) edition" (PDF). International Hydrographic Organization. 1953. Retrieved 28 December 2020.
- ^ "Russian map of Antarctica" (in Russian). Retrieved 5 July 2015.
- ^ "Riiser-Larsen Sea". The Free Dictionary (The Great Soviet Encyclopedia (1979)). Retrieved 5 July 2015.
- ^ Leitchenkov et al. 2008, Bathymetry, pp. 140–141
- ^ Kagami, Kuramochi & Shima 1991, Buried canyons in the Riiser-Larsen Sea, pp. 93–94; Discussion, pp. 94–97
- ^ Solli et al. 2007, Regional setting, pp. 44–45
- ^ Solli et al. 2007, Abstract; Conclusions, p. 55
- ^ Seton et al. 2012, East African margins, pp. 239–240
Sources
- Kagami, H.; Kuramochi, H.; Shima, Y. (1991). "Submarine canyons in the Bellingshausen and Riiser-Larsen Seas around Antarctica" (PDF). Proceedings of the National Institute of Polar Research Symposium on Antarctic Geosciences. 5: 84–98. Retrieved 18 February 2018.
- Leitchenkov, G.; Guseva, J.; Gandyukhin, V.; Grikurov, G.; Kristoffersen, Y.; Sand, M.; Golynsky, A.; Aleshkova, N. (2008). "Crustal structure and tectonic provinces of the Riiser-Larsen Sea area (East Antarctica): results of geophysical studies". Marine Geophysical Researches. 29 (2): 135–158. S2CID 140190106. Retrieved 18 February 2018.
- Seton, M.; Müller, R. D.; Zahirovic, S.; Gaina, C.; Torsvik, T.; Shephard, G.; Talsma, A.; Gurnis, M.; Maus, S.; Chandler, M. (2012). "Global continental and ocean basin reconstructions since 200Ma". Earth-Science Reviews. 113 (3): 212–270. . Retrieved 23 October 2016.
- Solli, K.; Kuvaas, B.; Kristoffersen, Y.; Leitchenkov, G.; Guseva, J.; Gandjukhin, V. (2007). "A seismo-stratigraphic analysis of glaciomarine deposits in the eastern Riiser-Larsen Sea (Antarctica)". Marine Geophysical Researches. 28 (1): 43–57. S2CID 128956568. Retrieved 18 February 2018.