Landslide risk is defined as the expected number of lives lost, persons injured, damage to property or
disruption of economic activity due to a particular landslide hazard for a specified time period within a
given area. In this study, quantitative landslide risk maps were prepared, between Mersin and Erdemli
region extending for 1600km2, considering landslide hazard, vulnerability and economic value of
elements at risk. 1285 and 338 residences were either collapsed or heavily damaged in Mersin city, due
to the landslides triggered by excessive rainfall in 1968 and 2001, respectively.
In order to determine the spatial probability of landslide occurrence, susceptibility maps were prepared
for particular time periods using statistical relationships between landslides and landslide conditioning
factors. Temporal probability of landslides was determined by considering the triggering factors from
rainfall – frequency relationships. The exceedance probability of landslides occurrence in 5, 10, 25, 50
and 100 years time intervals were calculated. The probabilities of landslide size (extent) were obtained
from frequency – size distribution of multi-temporal landslide inventory maps prepared after
interpretation of four sets of aerial photographs. Then, landslide hazard maps for different landslide
sizes (>0.1km2 and >0.01 km2), that will occur having exceedance probabilities for 5, 10, 25, 50 and
100 years periods were obtained. The elements at risk were considered only for roads (2916km),
houses (13780) and agriculture lands (169 km2). Vulnerability was assessed by comparing losses with
the actual economic value of the elements at risk and simply expressed as 1 for roads and houses, and
0.6 for agriculture lands.
Landslide risk maps were prepared by multiplying landslide hazard, vulnerability and actual economic
values of elements at risk. The results indicate that the total expected economic losses for 50-year
period of landslide sizes greater than 0.01 km2 and 0.1 km2 is about 243 million (economicvalue)and50million (%5.5 of total economic value), respectively. It is suggested that the
risk maps produced by this study would help to perform effective landslide risk mitigation strategies of the
region
