AUGUST 17, 1999 KOCAELI EARTHQUAKE -TURKEY

EARTHQUAKE INFORMATION

• Date: 1999-08-17 at  00:01:39.80(UTC), 03:01:37 a.m local time
• Surface Wave Magnitude: 7.8 (USGS)
• Body Wave Magnitude: 6.3 (USGS)
• Duration Magnitude: 6.7 (Kandilli)
• Moment Magnitude: 7.4 (USGS, Kandilli)
• Epicenter: 40.702N, 29.987E  (USGS)
• Depth: 17 km. (USGS)
• Fault plane solution

Location

An earthquake of magnitude Mw 7.4 occurred on the North Anatolian Fault Zone with a macroseismic epicenter near the town of Gölcük in the western part of Turkey.  Distribution of large aftershocks magnitude above 4 recorded  at USGS  are given below . Most of the aftershock activity is confined to the region bounded by 40.5-40.8N and 29.8-30.0E, which covers the area between Izmit and Adapazari to the east of the epicenter.

  Fault Rupture

 The right lateral displacement offset of NAF between Sapanca Lake and Izmit Gulf was reported as 2.60m.

 Prepared by G.Birgoren& C. Tarhan