HR: 0800h
AN: OS31A-0157    [Abstracts]
TI: Manifestations of the 15.11.2006 Kuril Tsunami Consequences on the Central Kuril Islands: the Reconstruction Events of the Destruction of Soil and Coastal Vegetation.
AU: * Levin, B
EM: levinbw@mail.ru
AF: Institute of Marine Geology and Geophysics of FEB RAS, 1b, Nauka Str., Yuzhno- Sakhalinsk, 693022, Russian Federation
AU: Kopanina, A
EM: avk@imgg.ru
AF: Institute of Marine Geology and Geophysics of FEB RAS, 1b, Nauka Str., Yuzhno- Sakhalinsk, 693022, Russian Federation
AU: Ivelskaya, T
EM: tanya.ivelskaya@gmail.com
AF: Sakhalin Tsunami Warning Center, Sakhalin Meteorology Administration, 78, Zapadnaja Str., Yuzhno-Sakhalinsk, 693000, Russian Federation
AU: Sasorova, E
EM: sasorova_lena@mail.ru
AF: P.P. Shirshov Institute of Oceanology,RAS, Nakhimovsky prosp., 36, Moscow, 117997, Russian Federation
AB: The investigation of the Central Kuril Islands (Simushir, Urup, Ketoy) coast was performance by the field survey for the Institute of Marine Geology and Geophysics FEB RAS (Yuzhno-Sakhalinsk) on the vessel "Iskatel-4" to be able find different deposits of the devastating tsunami waves influence on soil and vegetation. There were average run-up heights and inundation areas (tsunami flooding zones): h=6-9 m and 40-60 m (Ketoy); h=7-19 m and 80-300 m (Simushir). The field observation showed destruction of the soil layer. The estimation of water stream velocity for the hydraulic destruction of rocks enabled to receive velocity average mean for the water stream during tsunami dynamic inundation which may be in interval of velocities near 30 -50 m/sec. Field observations of coastal plants in tsunami inundation zones on Urup, Simushir and Ketoy Islands enabled us to recognize the character of destructive influence of tsunami waves to plant structure and essential signs of micro-phytocenoses for ecotopes at different distances from the coastline. Various plant species and vital morphes were found to indicate different reaction on sea waves. The investigation results showed that selected plant species demonstrate the strong response to tsunami wave inundation. We found that the most sensitive species to mechanical and physical- chemical tsunami impact are: Pinus pumila (Pall.) Regel and Phyllodoce aleutica (Spreng.) A. Heller. The character of plant damage shows in breaking of skeletal axes, infringement of root systems, and leaf dying. These findings allow us to use the species as effective indicators of tsunami flooding zone and estimation of tsunami run-up heights. Fulfilled analyzes let us to reconstruct possible events when tsunami hits to coast with specific shore morphology. The wave front at the slightly sloping coast (from coastline to first terrace) is characterized by uniform growth of water level when water moves away soil material (no more 2-3 cm) and micro- phytocenoses is maintaining the stability. During impact to steep dune slopes, tsunami wave generates violent horizontal streams which hit to sea-bank with velocities in order to 30m/sec and lead to considerable destructions of soil layer on the depth 30-35cm and structure damage of vegetation.
DE: 0439 Ecosystems, structure and dynamics (4815)
DE: 0468 Natural hazards
DE: 4564 Tsunamis and storm surges
DE: 4815 Ecosystems, structure, dynamics, and modeling (0439)
SC: Ocean Sciences [OS]
MN: 2007 Fall Meeting