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Depending on the earthquake zone,
rates vary from 0.014% to 0.14%.
Turkey has an earthquake fund.
Insurance and reinsurance companies
are required to contribute a portion of
their net retained premiums to the fund.
The premiums are retained for a 15-year
rolling period. However, as shown by
the Marmara earthquake, the fund is
minimally able to deal with the conse-
quences of a major earthquake. It is esti-
mated that the fund was less than
U.S.$30 million in 1999, while insured
losses were well over U.S.$1 billion.
Following the Marmara earthquake, the
World Bank has encouraged Turkey to
set up an adequate earthquake fund by
making aid subject to the introduction
Turkey shares its European borders with Greece and Bulgaria. The Aegean and of an independently managed National
Mediterranean Seas lie to the west and south. To the north lies the Black Sea. The north Earthquake Insurance Fund, which
and northeastern frontier is shared with Georgia and Armenia. Iran lies to the east and would require mandatory earthquake
Iraq to the south.
insurance. At this writing, details have
not been finalized.
Earthquakes in Turkey Most earthquakes in Turkey are associat-
ed with tectonic elements. Turkey is
by Christoph Schmidt located in a seismically active region
within the Mediterranean sector of the
Turkey is one of the more seismically active The area around and southeast of Alpine Himalayan orogenic system. This
areas in Europe as has been graphically Istanbul, along the Sea of Marmara and west-east running system extends from
demonstrated by the Marmara earthquake the Gulf of Izmit, is one of Turkey’s most the Mediterranean to Asia and is one
in August 1999. Marmara was one of the industrialized regions. It accounts for a of the world’s most seismically active
largest earthquakes to strike a modern, major part of the country’s manufactur- continental regions. The Alpine orogeny
industrialized area in recent history. This ing output, and for about half of is a result of the compressional motion
article will provide a short introduction Turkey’s insured values. There is also a between the Eurasian plate and the
into the earthquake exposures in Turkey high risk of earthquakes in this region, African plate.
as well as insurance covers and building which the recent Marmara quake
The majority of the region of Anatolia
codes. proved. The Marmara quake occurred in
(Turkey) and the Aegean Sea is located
August 1999 in western Turkey at the
Turkey is a link between Europe and the on the Anatolian (Turkish) plate. The
Eastern Marmara Sea, in a modern
Near and Middle East, with about 3% of northward motion of the Arabian plate
industrialized area, leaving over 17,000
its land area in Europe (Turkish Thrace) and African plate against the Eurasian
dead, with an estimated economic
and 97% in Asia (Anatolia). Its total plate squeezes the small Anatolian
cost of over U.S.$10 billion. Insurance
land area is comparable to the size of microplate westward relative to the
losses are considered to be between
Texas (301,380 sq. miles or 780,574 sq. Eurasian plate, causing earthquakes
U.S.$1 billion to U.S.$2 billion.
kilometers). along the North Anatolian fault. The
An insurance tariff for earthquake and North Anatolian fault constitutes the
Turkey’s capital city and seat of govern-
volcanic eruption was introduced in northern boundary of the Anatolian
ment is Ankara. It has just fewer than 4
Turkey in 1993. Earthquake, a fire plate. The southern boundary is formed
million inhabitants and is situated in
following and volcanic eruption can be by the East Anatolian fault, which joins
the center of the Anatolian plain.
covered either as a separate policy or the North Anatolian fault at Karlivo, and
Istanbul is another important city. Not
by endorsement. In general, limits are the Hellenic Arc to the south of Cyprus.
only is it Turkey’s largest city and port
identical to those given for main perils. The westward movement of the
with an estimated population of close
Policies usually contain a 72-hour clause. Anatolian plate and the collision of the
to 12 million, but also it is the main
African plate with the Eurasion plate
industrial, commercial and financial In January 1999, the tariff was modified.
causes compression, which produces a
center of Turkey. A mandatory 20% self-insurance applies.
subduction zone in the Aegean region.
Deductibles are between 2% and 10%
of the sum insured concerned. (continued on page 4)
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Magnitude:
Large earthquakes >M6+ - large dots
Small earthquakes <M6 - small dots
Depths of earthquakes:
0-33 km - changing slightly from
dark red (1km) to light red
34-70 km - yellow
70-150km - green
150-300 km - dark blue
Figure 1.
The North Anatolian fault is about 1200 suggest that another major earthquake ground. Along this area, at some clearly
kilometers long and extends in an east- is likely in the relatively near future. This identifiable places, the earthquake
west direction across the northern part theory has been developed and applied reached Modified Mercalli (MM) intensi-
of Turkey, parallel to the Black Sea coast. successfully for “mature” and geometri- ties of IX to X, devastating about half a
Historically this has been a seismically cally simple fault systems. Current dozen towns along the Bay of Izmit and
active area with over three dozen debate is about how this theory can be severely damaging others eastward
damaging earthquakes in the last extended to more complex systems as along the fault line. The earthquake
millennium. Earthquakes in the pull-apart basins like the Marmara Sea. could be felt as far as 425 kilometers
Anatolian fault system, such as the (See Figure 2.) from the epicenter.
1999 Marmara quake, occur very near
The 1999 Marmara earthquake occurred The death toll was an estimated 17,000,
the surface and can therefore cause
at a depth of 15.9 kilometers and lasted with a further 25,000 people injured
extreme damage. The west coast of
for about 45 seconds. The magnitude and 500,000 made homeless. Many of
Turkey is exposed to rather deep earth-
was 7.4, generating strong ground Turkey’s industrial facilities were severely
quakes from the Hellenic subduction
motion and moderate to high accelera- damaged, including the Tüpras refinery
zone. (See Figure 1.)
tions. Hundreds of aftershocks were felt in Korfez, which is Turkey’s biggest
The large earthquakes that have up to three weeks after the main shock. crude-oil refinery and a major supplier
occurred along the North Anatolian fault The largest one occurred on September to the industry in the area.
since 1939 progressed westward 13th and had a magnitude of 5.8.
It is estimated that the total economic
towards Istanbul like a line of falling
The origin of the earthquake was local- loss caused by the quake will reach
dominoes. This feature has been
ized at 40.70N/29.91E, about 11 kilo- U.S.$10 to $15 billion and the insured
observed at the North Anatolian fault at
meters southeast of Izmit and 90 kilome- loss will reach about U.S.$2 billion.
least twice before. Based on these obser-
ters east of Istanbul, with aftershocks Considering the widely spread under-
vations, scientists tried to adopt the
tightly following the North Anatolian insurance, the insured losses are effec-
hypothesis of stress-triggering for this
right lateral strike-slip fault. tively estimated below U.S.$1 billion. Of
area. Through the horizontal movement
this sum about 70% are industrial risks
of the Eurasian plate and the Anatolian The northern part of the North Anatolian
and 30% are residential and commercial
plate past one another, pressure was fault ruptured at a length of at least 125
risks. As for residential buildings, it
built up over a long period of time. kilometers, possibly even up to 160 kilo-
seems that the newest buildings and
Once stress is relieved through one meters (or 100 miles). The ground north
buildings between five and eight stories
earthquake, it can add stress to neigh- of the fault in average moved 2.5 meters
suffered the most severe damage,
boring fault patches, thus helping to set to the east and 1.5 meters to 2.0 meters
whereas smaller and older houses per-
off the next earthquake. Researchers downwards against the southern
formed quite well.
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The damages are attributable, to a large
extent, to the bad subsoil. Quaternary Comparison of the North Anatolian and San Andreas Faults
sediments are widely found at the
borders of the Bay of Izmit, providing
1939-1992 Earthquake Sequence
flat, easy ground to build on. This type
Izmit
of subsoil behaves especially unfavorably
Ercinzan
when hit by an earthquake, amplifying
the shaking of the building. Besides the Ankara
1939-1944 Progression
Fault Slip Rate
mentioned amplification of shaking, in 24 ± 4 mm/yr T U R K E Y
some areas of Quaternary sediments
the ground settled up to 2 meters.
500 Km
Los
Other causes of damage were inade- Angeles
San
quate quality of design, construction, Salton
1857 Earthquake Francisco
1906 Earthquake
and building control (i.e., frequent lack
Fault Slip Rate C A L I F O R N I A
of adequate transverse reinforcement 20-34 mm/yr
in reinforced concrete columns).
Apparently, construction companies
often engineer only one prototype and Similar slip rate, age, length and straightness
then use the same plan to build several
series of buildings without adapting the
design to local requirements and often Figure 2.
with deteriorating specifications.
Additionally, the use of poor and Another point the recent Marmara controls, disaster prevention methods
inappropriate construction materials earthquake illustrated was that the and research as well as the introduction
combined with sometimes poor efficiency of the government and other of a compulsory earthquake insurance
workmanship can add to the problem. official organizations in dealing with scheme. Government and Insurance
In addition, local authorities were disasters of this scale should be Association experts are in contact with
allowing structures to be built on improved. A condition of the World authorities and organizations in other
known active faults and in areas of Bank for providing aid for reconstruction earthquake-prone countries to share
high liquefaction potential. is the setting up of an Emergency knowledge on how to operate earth-
Disaster Management Agency and an quake insurance initatives and disaster
Buildings designed in accordance with earthquake disaster prevention research planning.
the building code suffered only minimal center.
damage. This indicates that the damage
and the deaths caused by the earth- Only months after the Marmara earth-
For additional information about this
quake could have been reduced if quake, on November 12, 1999, the
subject, please contact your local
authorities had strictly enforced the town of Düzce (Bolu Province) was
GeneralCologne Re underwriter; or
modern and highly earthquake-resistant struck by a 7.2 Richter scale earthquake.
contact Christoph Schmidt in London at
building code. Düzce is just 100 kilometers (or 65
+44 (0) 20 7426 6066 or
miles) from Izmit. The earthquake killed
Building codes and construction require- cschmidt@gcre.com, or Michael Spranger
at least 700 and injured over 5,000.
ments in Turkey are similar to those in Cologne at +49 221 3738 913 or
Düzce is not an industrial area and insur-
codes in California, however, since mspranger@gcre.com.
ance losses are likely to be low. Once
enforcement by the Turkish government again poor construction, deficient build-
is rather poor, building codes are widely ing materials, and non-observance of
ignored. Many buildings are built with- building codes are believed to have
out authorization. In Turkey these build- contributed considerably to the
ings are called “gece kondu,” meaning damage caused.
“build overnight.” This goes back to a
historic regulation that deems structures The damages caused by the disasters
to be legal if they are completed in 1999 are attributable, to a very large
overnight. Even though it is hard to extent, to the bad subsoil. Nevertheless,
believe that any large structure can be the most critical lesson learned is that
erected in such a short period, it high- strict enforcement of building law and
lights the problem of insufficient control regulations by the authorities are crucial
by the authorities. The Turkish Chamber in preventing similar disastrous effects in
of Commerce estimates that only about the future.
one-third of all structures comply with To address this, the World Bank, for
building codes. example, has made financial aid
conditional upon improved construction
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