Long Period Seismic Waves Developed at Local Distances

Öz

Long period seismic waves has two types. One of them is caused from far-source earthquakes and the other one is caused from near field type earthquakes. (Koketsu and Miyake, 2008)  Long period seismic waves could be really destructive since these kind of waves amplify their effect when they are passing through the sediman areas. There are many examples in literature. A devastating example is Mexico City, which is located 400 km away from the 1985 Michoacan Earthquake (Mw=8.0) (Celebi et al, 1987). This study’s aim is to detect the long period seismic waves which will effect Marmara Region and generate relationship according to path and source.  On May 24, 2014 Mw=6.9 Gökçeada earthquake was occurred and after this event, there were far source long period ground waves observed at Marmara Region. We used 5 stations to compare the wave characteristic. Gökçeada station is the closest station and 40 km away, the other 4 stations are 300 km away from the epicenter and they are located at near İstanbul. We observed long period seismic waves at these stations.  For future works, the aim is to make a long period ground waves map for Marmara Region especially for İstanbul, and calculate their effect.

Anahtar Kelimeler

• Long period sesimic waves,near field,far source,Marmara Region

Kaynakça

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