THE MORPHODYNAMICS OF NAGAEV BAY COASTS, THE SEA OF OKHOTSK
https://doi.org/10.15356/0435-4281-2012-4-45-52
Abstract
According to the results of long-term field observations and remote sensing studies, the coasts of Nagaev Bay have been forming due to both tectonic movements and rare earthquakes, which drastically accelerate slow relief-forming processes, and also to abrasion-favored slope processes. During the past decade, the eastern cliff of the bay has been subjected to intense abrasion and slope denudation processes. Unlike the southern and northern coasts, which are rocky, it consists of poorly lithified siltstone and argillite rocks and recedes onshore about 1 m/year. As a result, the territory of Magadan lessens by about 2000 m2 every year. Relatively large rock falls and rockslides are of about 14 000 m3 and become more significant and frequent in autumn (to the less extent in spring) due to freezing/thawing processes in surface soils. The question of what can be the cause for intense cliff destruction, whether it can be the sea level rise and/or subsidence of the rift-shaped bottom of Ghertner-Nagaev Depression, needs further investigation.
About the Author
B. P. VazheninRussian Federation
References
1. Geologiya SSSR. V. XXX. Severo-Vostok SSSR. Geologicheskoye stroeniye (Geology of the USSR. V. XXX. NE of the USSR. Geology). Moscow: Nedra (Publ.), 1970. Book 1, 548 p., Book 2, 536 p. (in Russ.).
2. Stratigraficheskiy slovar’ SSSR. Paleogen, neogen, chetvertichnaya sistema (Stratigraphic dictionary of the USSR, Paleogene, Neogene, Quaternary system). Leningrad: Nedra (Publ.), 1982, 616 p. (in Russ.).
3. Berega (Coasts). P.A. Kaplin, O.K. Leontyev, S.A. Lukyanova, L.G.Nikiforov, Eds. Moscow: Mysl’ (Publ.), 1991, 479 p. (in Russ.).
4. Vazhenin B.P. Printsipy, metody i resul’taty paleoseismologicheskikh issledovaniy na Severo-Vostoke Rossii (Principles, methods and results of the paleo-seismjgeological survey in the NE of Russia). Magadan: SVKNII DVO RAN (Publ.), 2000, 205 p. (in Russ.).
5. Vazhenin B.P., Lebedintsev A.I. Rockfalls on the sea coasts: their significance for the past colonization of the northern Okhotsk Sea region. In: Neolit i paleometall severa Dal’nego Vostoka (Neolith and paleo-metal epochs in the north of the Far East). Magadan: SVKNII DVO RAN (Publ.), 2006, pp. 164–175 (in Russ.).
6. Vazhenin B.P. Large rockfalls in the northern coasts of the Sea of Okhotsk. In: Geologiya, geografiya, biologicheskoye raznoobrazie I resursy Severo-Vostoka Rossii (Geology, geography, biological diversity and resources of the North-East of Russia). Magadan: SVNTs DVO RAN (Publ.), 2011, pp. 80–82 (in Russ.).
7. Alekseev M.D., Onukhov F.S., Ufimtsev G.F. Fault-induced rockfalls on the northwestern coasts of the Sea of Okhotsk. Geologiya i geofizika (Geology and Geophysics, FEB RAS), 1975, no. 8, pp. 87–95 (in Russ.).
8. Ufimtsev G.F. Fault-induced rockfalls as a kind of displacements in the near-surface parts of lithosohere. Tikhokeanskaya geologiya (Pacific geology, FEB RAS), 1993, no. 1, pp. 31–38 (in Russ.).
Review
For citations:
Vazhenin B.P. THE MORPHODYNAMICS OF NAGAEV BAY COASTS, THE SEA OF OKHOTSK. Geomorfologiya. 2012;(4):45-52. https://doi.org/10.15356/0435-4281-2012-4-45-52
Email this article 