The 2008 Earthquake in Kunak, East Sabah
Writer : Felix Tongkul
Date : 13-14 Dec 2012
Publisher : National Technical Seminar on Earthquake and Tsunami, Petaling Jaya, Selangor
A moderate earthquake of magnitude 5 occurred in Kunak District on 18 May 2008 around 2.26pm. The epicenter of the earthquake was located at Lat 4.600N and Long 118.170E at a very shallow depth of 10km. The earthquake was felt as far as Lahad Datu and Tawau town areas. Another weak earthquake of magnitude 3.7 was recorded by MMD at 11.52pm on the same day offshore Kunak at Lat 4.70N and Long 118.60 E. A site visit to assess the impact of the earthquake was carried out on the 27 May 2008. Some of the sites which incurred minor damage included stone wall houses in Bukit Tajam Estate, minarets in a mosque in Kampung Tun Fuad, concrete floor of Giram Oil Palm Mill and concrete floor and walls of Millimewa Supermarket. The mud volcano near Tingkayu Estate appeared to have been activated by the tremor. The focal mechanism solutions provided by the International Seismological Centre for the 2.26pm earthquake indicate two possible strike-slip fault-plane solutions, NW-SE left lateral slip and NE-SW right lateral slip. Field observations together with geological inputs suggest that the earthquake was generated by horizontal movement along a NW-SE fault plane. This active strike-slip fault is thought to be related to on-going WNW-ESE tectonic compression in Sabah and surrounding areas.