Gölcük has always risk of eartquake , because it found on active fault line . Also ıt can be affected by earthquake which occur in Sea of Marmara . The biggest collapse occur in two main regions . These are coastal part and alluvium part . Moreover old residential area had many stores buildings , structure of buildings affected the speed of collapse Aslanbey Formation is the best place for settlement . Also new residential area has maxsimum two or there stores buildings . So new residential area is the best place for settlement .