Great Earthquake-Generated Events - Tsunami - page 114

Table 6.4 Maximum run-up heights for the December 26, 2004

(Klostermann et al. 2014 ), Thailand/Malaysia (Brill et al.
2011 ; Prendergast et al. 2012 ); West Aceh Province,
Indonesia (Monecke et al. 2008 ), and the Maldives in the
center of the Indian Ocean (Mörner and Dawson 2011 ;
Klostermann et al. 2014 ). Tsunami layers have been dated
using conventional radiocarbon and optical luminescence
dating. The mean date for each tsunami layer found in these
countries is plotted in Fig. 6.13 . No event is evident across
all five countries. This may reflect variations in the intensity
of tsunami across the region, poor chronologies, or poor
preservation potential of sand bodies in marshy, tropical
settings. Given the error margin in the dates, regional
communality exists for large tsunami at *230,
*600,*1200,*4100 year, and *6250 BP. The data are
suggestive of a recent recurrence interval of 400-500 years.
The number of paleo-tsunami layers found also indicates
that the northeast Indian Ocean is a dangerous region for
tsunami and that this risk has been underestimated.
The 2004 tsunami's impact in the region was horrific.
For the first time, modern communications and the avail-
ability of video cameras in the hands of thousands of
tourists brought the disaster into living rooms almost as it
happened. Despite this instant communication, warnings
were futile. The Pacific Tsunami Warning Center in Hawaii
at first did not realise the magnitude of the event because
automatic computer algorithms were tuned to shorter seis-
mic wavelengths and yielded an initial M w magnitude of
8.0. When it was realised that this was grossly underesti-
mating the size of the event, there was no mechanism to
warn countries in the Indian Ocean because none of the
countries being affected belonged to the Pacific Warning
Network. Such a warning may have been futile on Sumatra.
Sumatra was simply too close to the epicenter, and the
majority of the population too far from high land to flee to
safety within the 20 to 30 min that it took the tsunami to
reach the coast.
Table 6.6 shows the final death toll for thirteen countries
where deaths occurred (United Nations 2006 ). Because the
tsunami propagated outwards parallel to the fault rupture,
very little of the wave traveled north or south through the
Indian Ocean. Only two people died in Bangladesh. The
wave also had little impact on the African coast. However,
in Sumatra, Sri Lanka, and Thailand, it was a major disaster.
The final death toll amounted to 229,866 people, the largest
for any tsunami event and one of the greatest for any natural
disaster. The biggest death toll occurred in Sumatra where
at least 165,000 people died. This tally alone surpasses the
death toll for any previous tsunami event. The tsunami
arrived in Thailand at 10:00 AM and had a significant
impact upon tourist resorts where tourists were just starting
their day on the beaches. The death toll on these beaches
was over 8,000 including Bhumi Jenson, the 21-year old

Indian Ocean Tsunami
Country Location Latitude Longitude Max

height
(m)

Indonesia Labuhan 5 72 0 95 14 0 50.9

9 02 0 98 15 0

Thailand Ban Thung Dap 20.0

5 18 0 100 19 0 Malaysia Pasir Panjang 7.4

13 56 0 98 05 0 Myanmar Sann Lan Village 2.9

10 35 0 92 34 0

Andaman-
Nicobar
Is

Passenger Jetty,
Little
Andaman

16.5

India Devanampattinam 11 44 0 79 47 0 11.5

Sri Lanka Patanangala

Beach

6 21 81 30 0 11.3

Maldives Fanadhoo, Laamu 1 50 0 73 30 0 4.4
Madgascar Faux Cap -25 34 0 45 32 0 5.4
Source Choi et al. ( 2006 ), and National Geophysical Data Center
( 2006b )

Table 6.5 Maximum distance inland for the December 26, 2004
Indian Ocean Tsunami
Country Location Latitude Longitude Distance

(m)

Indonesia Multiple - - 5000

Thailand Ban Nam Kim 8 52 0 98 17 0 1673

Malaysia Penang Island 5 20 0 100 12 0 3000

Myanmar - - - 610

11 30 0 92 43 0 Andaman-

Nicobar
Is

Port Blair 500

India Cuddalore 11 46 0 79 47 0 1500
Sri Lanka Polhena 5 10 0 80 32 0 905
Maldives Kulhudhuffushi 6 37 0 73 04 0 155
Source Choi et al. ( 2006 ), and National Geophysical Data Center
( 2006b )

the event. However, five locations have been found where
three to five units of fining upward sand, ranging from
11 cm to 30 cm in thickness, were deposited (Hawkes et al.
2007 ). Again, there was no one-to-one relationship between
the number of waves and the number of units. The coarse
sand at the bottom of units was deposited under turbulent
uprush or backwash deposition, while the fining upward
sequences were deposited during periods of waning flow.
Paleo-tsunami studies identifying past tsunami events in
the area show that the Indian Ocean has had many major
tsunami events over the past 7,000 years similar in size and
destruction to the December 26, 2004 Tsunami. Studies
have been conducted in Sri Lanka (Jackson 2008 ), India