Uniform basin growth over the last 500 ka, North Anatolian Fault, Marmara Sea, Turkey
Acoustic data that image below the sea floor (“seismic reflection data”) show a stack of glacial period deltas beneath Marmara Sea, Turkey, south of Istanbul. These deltas formed the basis for a stratigraphic age model for the last half million years (Green horizon ~540,000 years old). This age model was correlated to the main active strand of the North Anatolian fault close (15 km) to Istanbul. Vertical components of slip, as well as right-lateral transport of a series of depo-centers indicate steady-state deformation on this fault. This contrasts to several publications from the last decade which suggest that this fault initiated only 200,000 years ago. Older, large displacement faults may be capable of longer ruptures and thus larger magnitude earthquakes.
Graphic Credit: Chris Sorlien