The 1999 Düzce earthquake occurred on 12 November at with a moment magnitude of 7.2 and a maximum Mercalli intensity of IX (''Violent''), causing damage and at least 845 fatalities in
Düzce
Düzce () is a city in northwestern Turkey, the capital city of Düzce Province, the eighty-first Provinces of Turkey, province in the country. It is the seat of Düzce District.Turkey
Turkey, officially the Republic of Türkiye, is a country mainly located in Anatolia in West Asia, with a relatively small part called East Thrace in Southeast Europe. It borders the Black Sea to the north; Georgia (country), Georgia, Armen ...
. The
epicenter
The epicenter (), epicentre, or epicentrum in seismology is the point on the Earth's surface directly above a hypocenter or focus, the point where an earthquake or an underground explosion originates.
Determination
The primary purpose of a ...
was approximately to the east of the extremely destructive
1999 Ä°zmit earthquake
An earthquake of moment magnitude 7.6 struck Kocaeli Province, Turkey on 17 August 1999. According to official figures, at least 18,373 people died and 48,901 people were injured during the earthquake, and 5,840 people were missing. At least 15 ...
that happened nearly three months earlier. Both
strike-slip
In geology, a fault is a planar fracture or discontinuity in a volume of rock across which there has been significant displacement as a result of rock-mass movements. Large faults within Earth's crust result from the action of plate tectonic ...
earthquakes were caused by movement on the
North Anatolian Fault
The North Anatolian Fault (NAF; ) is an active right-lateral strike-slip fault in northern Anatolia, and is the transform boundary between the Eurasian plate and the Anatolian sub-plate. The fault extends westward from a junction with the Ea ...
.
Tectonic setting
The western and central parts of Turkey lie on the eastern part of the
Anatolian plate
The Anatolian plate is a continental tectonic plate lying under Asiatic part of Turkey, known as Anatolia. Most of the country of Turkey is located on the Anatolian plate. The plate is separated from the Eurasian plate and the Arabian plate ...
, which is currently being forced to the west by the continuing northward movement of the Arabian plate. In northern Turkey, this westward motion is taken up by a major zone of dextral (right-lateral) strike-slip, the North Anatolian Fault. The 1999 Düzce event is the most recent in a sequence of large earthquakes that have affected the North Anatolian Fault, starting towards the eastern end with the
1939 Erzincan earthquake
An earthquake struck Turkey's eastern Erzincan Province at with a moment magnitude () of 7.8 and maximum Mercalli intensity of XII (''Extreme''). It is tied with the 2023 Turkey–Syria earthquakes as the most powerful earthquake in Turkey to ...
, then propagating towards the west with events in
1942
The Uppsala Conflict Data Program project estimates this to be the deadliest year in human history in terms of conflict deaths, placing the death toll at 4.62 million. However, the Correlates of War estimates that the prior year, 1941, was th ...
,
1943
Events
Below, the events of World War II have the "WWII" prefix.
January
* January 1 – WWII: The Soviet Union announces that 22 German divisions have been encircled at Stalingrad, with 175,000 killed and 137,650 captured.
* January 4 †...
,
1944
Events
Below, the events of World War II have the "WWII" prefix.
January
* January 2 – WWII:
** Free France, Free French General Jean de Lattre de Tassigny is appointed to command First Army (France), French Army B, part of the Sixt ...
,
1951
Events
January
* January 4 – Korean War: Third Battle of Seoul – Chinese and North Korean forces capture Seoul for the second time (having lost the Second Battle of Seoul in September 1950).
* January 9 – The Government of the Uni ...
,
1957
Events January
* January 1 – The Saarland joins West Germany.
* January 3 – Hamilton Watch Company introduces the first electric watch.
* January 5 – South African player Russell Endean becomes the first batsman to be Dismissal (cricke ...
,
1967
Events January
* January 1 – Canada begins a year-long celebration of the 100th anniversary of Canadian Confederation, Confederation, featuring the Expo 67 World's Fair.
* January 6 – Vietnam War: United States Marine Corps and Army of ...
and finally the 1999 Ä°zmit event. At its western end the North Anatolian Fault splits into two main segments, with the northern of these giving rise to the 1999 earthquakes.
Earthquake
The earthquake had an estimated magnitude in the range 7.1–7.2 on the moment magnitude scale. The
International Seismological Centre
The International Seismological Centre (ISC) is a non-governmental, nonprofit organisation charged with the final collection, definitive analysis and publication of global seismicity. The ISC was formed in 1964 as an international organisation ...
gives a magnitude of 7.16±0.1 for this event in their catalogue. The maximum measured intensity was IX at a seismometer about 4 km from the epicentre, with a peak ground acceleration of 147.80%g and a peak ground velocity of 113.02 cm/sec.
Ground rupture
A
surface rupture
In seismology, surface rupture (or ground rupture, or ground displacement) is the visible offset of the ground surface when an earthquake rupture along a Fault (geology), fault affects the Earth's surface. Surface rupture is opposed by buried rup ...
of 40 km was identified in the field along the Düzce Fault, part of the northern splay of the North Anatolian Fault. This was extended by an additional 15 km at the eastern end using
SPOT
Spot or SPOT may refer to:
Places
* Spot, North Carolina, a community in the United States
* The Spot, New South Wales, a locality in Sydney, Australia
* South Pole Traverse, sometimes called the South Pole Overland Traverse
People
* Spot Coll ...
imagery. The maximum identified lateral displacement was 5 m, with an average displacement of 3 m. At the western end of the fault, there was a maximum 3.5 m of vertical displacement.
Rupture propagation
Analysis of
seismometer
A seismometer is an instrument that responds to ground displacement and shaking such as caused by quakes, volcanic eruptions, and explosions. They are usually combined with a timing device and a recording device to form a seismograph. The out ...
records suggests that the rupture propagated towards the east faster than the
S wave
__NOTOC__
In seismology and other areas involving elastic waves, S waves, secondary waves, or shear waves (sometimes called elastic S waves) are a type of elastic wave and are one of the two main types of elastic body waves, so named because t ...
velocity ( supershear) and to the west slower than the S-wave velocity. Supershear rupture propagation is characteristic of strike-slip earthquakes, particularly on fault segments that are relatively simple and planar in geometry.
Impact
Düzce and surrounding areas had already been quite badly affected by the İzmit earthquake a few months earlier, so that many buildings were already in a weakened state when the November earthquake struck.
The death toll in Düzce was 478, with an additional 313 fatalities in Kaynaşlı and 48 more in
Bolu
Bolu is a city in northern Turkey, and administrative center of the Bolu Province and of Bolu District, A significant number of deaths were attributed to the presence of traditional heaters causing fires and related smoke effects, particularly in Kaynaşlı. Thirty people were also injured in
List of earthquakes in Turkey
Turkey has had many earthquakes. This list includes any notable historical earthquakes that have epicenters within the current boundaries of Turkey, or which caused significant effects in this area. Overall, the population in major cities like ...