Geoscience Reference
In-Depth Information
THE STUDY AREA AND DATA
A devastating earthquake with a magnitude of Mw 7.4 occurred on the NAFZ of Turkey
on August 17, 1999 at 00:01:39 UTC (3:01 am local time). The center of the earth-
quake was at 40.74 N, 29.86 E. The earthquake struck Kocaeli and surrounding cit-
ies, namely Adapazari, Golcuk, and Yalova, and brought about massive destruction
to these cities and their surrounding rural areas. This was one of the most destructive
earthquakes of the 20th century considering the amount of damage and number of
casualties. At least 17,118 people were killed, approximately 50,000 injured and the
estimated financial loss in Istanbul, Kocaeli, and Adapazari was 3-6.5 billion US dollars
(Kaya et al., 2005; Sertel et al., 2007; USGS, 2008).
This research investigates the earthquake induced changes in the city center of
Adapazari where the recorded number of collapsed buildings was 11,373 (Sertel et al.,
2007). The district of Adapazari is located in the northeastern part of the Marmara
Region, Turkey, covering 29°57´-30°53´ N and 40°17´-41°13´ E. The population of
the Adapazari inner city was 169,099, 184,013, and 172,000 in 1990, 1997, and 2000,
respectively (TSI, 2008).
The SPOT HRVIR panchromatic images obtained before (June 25, 1999) and after
(October 4, 1999) the earthquake were used in the research. These images have 10 m
spatial and 8 bit radiometric resolution. The 1/5,000 scale digital damage map illus-
trating the degree of earthquake damage was used to analyze the accuracy of the pro-
posed method. This map was produced by local and federal authorities by conducting
a fi eld survey on the building base after the earthquake.
Figure 1.
Location of the study area, (a) Turkey and surrounding countries, (b) Marmara Region, star
shows the epicenter of the earthquake.
