The indian ocean tsunami and its impact on andaman islands: a detailed post-tsunami field study
||International Journal of Biotech Trends and Technology (IJBTT)|
|© 2013 by IJBTT Journal|
|Volume - 3 Issue - 3
|Year of Publication : 2013|
|Authors :K. Ilayaraja, R. R. Krishnamurthy, S. M. Hussain|
K. Ilayaraja, R. R. Krishnamurthy, S. M. Hussain "The indian ocean tsunami and its impact on andaman islands: a detailed post-tsunami field study",International Journal of Biotech Trends and Technology (IJBTT), V3(3):55-62 July - September 2013. Published by Seventh Sense Research Group.
This paper is a report on the field observation undertaken through the DST project immediately after the occurrence of December 26, 2004 earthquake of magnitude >M 9.0 that occurred off the west coast of Sumatra Island of Indonesia with its epicenter located on the shallow depths in the Indian Ocean. The tsunamigenic earthquake that occurred on 26th December 2004 in the Indian Ocean caused severe damage and claimed many victims in some coastal villages through out the Islands. The main purpose of the survey was to assess morphological changes caused by the wave attacks and to evaluate the impact of the event on buildings, bridges and infrastructure. Attention was predominantly focused on the entire group of Andaman Islands such as Diglipur (North Andaman), Mayabunder, Baratang and Rangat (Middle Andaman) and Port Blair, Havelock and Hut Bay areas (South Andamans and Little Andamans), were examined for the most affected places in the islands. The most severe damage was observed at Hut Bay, in Little Andaman, where the buildings and coastal walls and the jetties were almost levelled by the violent waves. Most places were hit by these waves with documented wave height often exceeding 2-5 m according to the evidence by the local people and by filed investigations. The coastal landforms are changed and stagnation of the tsunami water is seen in the low lying areas of South Andaman. On the west coast of the Andaman, the coastline witnessed the raised reef flats to above the present day high tide mark, similar uplift of shallow fringing reefs. It was observed that a few kilometres of shallow water reef are now dead in the Diglipur area of North Andaman. In Sippighat creek (South Andaman) area, it was observed that the Mangrove was completely submerged with seawater and completely turned brownish, indicating that it had been dead. As a sequel, the maximum damage has been taken place to the structures very close to the low laying areas of the coast and severe impact has been noticed on the mangrove forest of Baratang and south Andaman localities. It is further noticed that few mud volcanoes of Baratang area became activate and started ejecting heavier mud.
1. Baptista, A. M, Priest, G. R. and Murty, T. S. (1993). “Field survey of the 1992 Nicaragua tsunami”, Marine Geodesy 16, 169–203. 2. Hussain, S. M, Krishnamurthy, R. R, Suresh Gandhi, M, Ilayaraja, K, Ganesan, P. andMohan, S. P. (2006). “Micropaleontological investigations of tsunamigenic sediments of Andaman Islands”. Curr. Sci., vol.91, 1655 – 1667. 3. Imamura, F, Synolakis, C.E, Gica, E, Titov, V, Listanco, E. and Lee H.G. (1995). “Field survey of the 1994 Mindoro Island, Philippines tsunami”, Pure Appl.Geo- phys., 144, 875 - 890. 4. Ramanamurthy M.V, Sundaramoorthy, S, Pari, Y, Ranga Rao, V, Mishra, P, Bhat, M, Tune Usha, Venkatesan, R. and Subramanian, B. R. (2005). “Inundation of seawater in Andaman and Nicobar Islands and parts of Tamil Nadu Coast, India, during 2004 Indian ocean Tsunami”, Current Science, Vol. 88(11),1736 – 1740. 5. Salvador f. Farreras. (2000). “Post Tsunami Field Survey Procedures: An Outline”, Natural Hazards 21, 207–214. 6. Yeh, H, Imamura, F, Synolakis, C, Tsuji, Y, Liu, P. and Shi, S. (1993). “The Flores island tsunamis”, EOS Trans. AGU, 74 (33), 369, 371-373.
Tsunami, impacts, corals, mangroves, creeks, beaches, Andaman.