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destructive tsunami followed an earthquake on December
28, 1908 in the Messina Strait region. A small proportion of
the 60,000 people killed during this event were drowned by
the tsunami, which flooded numerous coastal villages and
reached a maximum run-up exceeding 10 m in elevation.
There have been two mega-turbidite deposits with volumes
of 300-600 km 3 mapped on the Balearic Abyssal Plain
south of France and on the Herodotus Abyssal Plain north of
Libya (Rothwell et al. 2000 ). They are the products of
tsunami, with the latter being related to the eruption of
Santorini around 1470 BC, and the former to slope failure at
times of lower, global sea level.
Frederiksted, St. Croix, and was recorded at Galveston,
Texas. The latter event followed a magnitude 8.1 earth-
quake off the northeast coast of the Dominican Republic.
Locally, the tsunami penetrated several kilometers inland
and drowned about 1,800 people. It also was observed at
Daytona Beach, Florida. Harbitz et al. ( 2012 ) simulated the
threat of tsunami in the Caribbean. They found that about
252,000 and 130,000 people were vulnerable to earthquake-
and landslide-induced tsunami respectively with Puerto
Rico and Venezuela most at risk. Countries that had the
highest exposure relative to population were Antigua
(7.5 %) and Guadeloupe (6.5 %). Most of these countries
have less than 1 h warning before the arrival of a tsunami.
1.5.2
Caribbean Sea
1.5.3
Pacific Ocean Region (including
Indonesia)
The Caribbean—including the south coast of the United
States—is particularly prone to tsunami as the Caribbean
Plate slides eastward relative to the North American Plate at
a rate of 2 cm yr -1 , producing strong seismic activity in the
Puerto Rico Trench. The area adjacent to Venezuela has a
reputable geological record of multiple tsunami events
(Scheffer 2004 ). The Caribbean is subject to tsunami from
earthquakes, volcanoes, and submarine landslides (Harbitz
et al. 2012 ). Unfortunately, the threat has been overshad-
owed by the more frequent occurrence of tropical cyclones
or hurricanes. About 160 landslides have been mapped with
the largest predicted tsunami run-up height being 16 m
along the northern coast of Puerto Rico. A limestone block
150 million m 3 in size slid off of Curaçao Island in the
Netherlands Antilles 5000-10000 years ago. The historical
record of tsunami is one of the longest in North America
with the first reported tsunami occurring in Venezuela in
1498 (National Geophysical Data Center and World Data
Center A for Solid Earth Geophysics 1989 ; Lander and
Lockridge 1989 ; Harbitz et al. 2012 ). Since then there have
been 84 other events. A total of 74 % of the tsunami were
caused by earthquakes, 14 % by volcanoes, and 7 % by
landslides. Only 5 % have an unknown origin (Harbitz et al.
2012 ). The devastating Port Royal, Jamaica Tsunami in
June 1692 drowned 3,000 people. An earthquake that sent
much of the city sliding into the sea triggered the tsunami.
Ships standing in the harbor were flung inland over two-
story buildings. An earthquake in the Anegada trough
between St. Croix and St. Thomas produced another sig-
nificant tsunami on November 18, 1867. The resulting
tsunami reached 7-9 m at St. Croix, 4-6 m high at St.
Thomas, 3 m at Antigua, and 1-6 m in Puerto Rico. Run-
ups of 1.2-1.5 m were common elsewhere throughout the
southern Caribbean. Other notable events have occurred in
1842, 1907, 1918, and 1946. Of these, two bear mention:
the tsunami of October 25, 1918 and August 4, 1946. The
former event had a maximum run-up height of 7 m at
Figure 1.2 a plots the distribution of 1,274 observations of
tsunami reported along the coastlines of the Pacific Ocean
and Indonesian regions between 47 BC and the end of the
20th century (Lockridge 1985 ; Lockridge 1988b ; Intergov-
ernmental Oceanographic Commission 1999a ). The size of
the circles is proportional to the number of observations per
degree square of latitude and longitude. The data are biased
in that the same event can be recorded at more than one
location. The map excludes 217 observations that cannot be
precisely located. The distribution of all the observations
plotted in Fig. 1.2 a is tabulated by region in Table 1.2
(Intergovernmental Oceanographic Commission 1999a ).
Because some countries have better observation networks
than others, smaller events are overemphasized. This is true
of the west coast of North America, which is overrepre-
sented in the modern record, despite having records of tsu-
nami for only the last 230 years. Some countries are
underrepresented in Fig. 1.2 a. For example, over a hundred
observations from Australia are not included. The coastline
of Japan has the longest historical record of tsunami, with
25.2 % of all events originating here. One other region also
stands out as having a high preponderance of tsunami—the
coast of South America with 21.3 % of events. A few small
areas are highly prone to tsunami, sometimes from distant
sources. These areas include northern California, Hawaii,
southwest Chile, and the Chile-Peru border region.
Destructive tsunami have inundated the Chilean coast at
roughly 30-year intervals in recorded history.
Large tsunami originating from earthquakes with mag-
nitudes greater than 8.2 affect the entire Pacific Ocean once
every 25 years. Figure 1.2 b plots the source region of
ocean-wide events. Major events for the Pacific Ocean are
listed in Table 1.3 (Lockridge 1988b ; Intergovernmental
Oceanographic Commission 1999a ; National Geophysical
Data Center 2013 ). Significant events have increased in
 
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