1. Recent Seismicity in the Mozambique Region by T T Molea and L Akromah (Council for Geoscience: Seismology Unit)‏ Seisan workshop October 2008 Norway

2. OUTLINE  The East African Rift System as a source of tectonics  Seismicity of southern Africa 1620 - 2007  Mozambique earthquake of 22/02/2006  Conclusion

3. The East African Rift System

4. Seismicity of southern Africa (1620 – 2007)‏

5. 609 Recording Stations

6. Location & Magnitude –USGS :7.4 –CTBTO: 6.4 –CGS :7.2. –Epicentre : Machaze, in the ( Manica Province of Mozambique)‏ –Recording Time –22:19:05.8. –This is believed to be the largest instrumentally recorded earthquake in Mozambique.

7. Epicentre by USGS

8. Damage & Intensity Maximum vertical displacement; ± 2m. Maximum horizontal displacement; ± 60km. Shaking was strong enough to kill 4 people and injured at least 29 more. Felt by people throughout Mozambique as well as in parts of the neighbouring countries of South Africa,Swaziland, Zambia, Zimbabwe.

9. Displacement

10. Seismological Action Taken – Location by: USGS, CTBTO & CGS. – Moment Tensor by Harvard University – Source of earthquake mechanism investigated by Fenton & Bommer of Imperial College London. – Field survey by the DNG ( geological survey) of Mozambique.

11. Conclusion  This was the largest instrumentally recorded seismic event in Mozambique.  The event was felt over a wide area, thus leading to the suspicion that the attenuation in southern Africa is lower than previously thought.  The earthquake occurred on a previously unknown lineament which begs the question whether other capable geologic features may be present in the area.

12. Thank You

13. IASPEI 2009 General Assembly The Council for Geoscience invites you to attend the first IASPEI General assembly in Cape Town from 10-16 January 2009. Summer-school 19-24 January 2009 Registration 31 October 2009 www.IASPEI2009sa.com email: iaspei2009@geoscience.org.za Hope to meet you all in Cape Town!!!

14. Seismic pattern of Southern Africa –Tectonics movement of fault plates in the East Africa Rift Valley. –Rift consist of 2 main lines : E & W branch. –W.branch starts in Lake Albert - DRC through Lake Malawi & terminate in S. Mozambique. –E. branch extends from triple junction between, Arabian,Nubian & Somalian plates in the North to Southern Tanzania. –A third south-eastern branch continue through the Mozambique channel.