Active faults and fault segmentation in the Dodoma area, Tanzania: A first assessment of the seismic hazard in the area
Macheyeki, A. S. ; Delvaux, D.; De Batist, M.; Mruma, A. H. (2009). Active faults and fault segmentation in the Dodoma area, Tanzania: A first assessment of the seismic hazard in the area. Tanzanian Journal of Earth Sciences 1: 38-57
In: Tanzanian Journal of Earth Sciences. Geological Survey of Tanzania: Dodoma. ISSN 1821-5637, more
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| Author keywords |
Tanzania; Dodoma fault segmentation; displacement profile; seismic hazard |
| Authors | | Top |
- Macheyeki, A. S., more
- Delvaux, D., more
- De Batist, M., more
- Mruma, A. H.
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| Abstract |
Dodoma, the capital of Tanzania, was hit by a 5.5 magnitude (Mw) eathquake during a parliamentary session on November 4, 2002. It was part of a seismic crisis with 37 events of magnitude (Mw) ranging from 3.7 to 5.5., from early 2001 to late 2004 and centered about 80 km north of Dodoma. This paper re-evaluates the active tectonic setting of the Dodoma area, using combined integration of existing geological and topographic maps with the recently released SRTM DEM with a GIS. Main emphasis is put on morphotectonic analysis of potentially active fault scarps using topographic elevation data extracted from the SRTM DEM. The ongoing study has revealed that the Mponde and Bubu faults are seemingly the active faults or most likely so as compared to other faults in the Dodoma area.The Saranda and the Bubu faults have three fault segments each. For the Saranda fault, the fault segments are here-by called Saranda south (> 11 km), Saranda mid (29 km) and Saranda north (24 km). The Gonga (42 km), Makutupora (30 km) and Nkambala (33 km) are fault segments which form the Bubu fault. Similarly, the Hombolo fault has two fault segments namely the DAM fault segment (18 km) and the Nzuguni fault segment (> 19 km) with total length of the order of 40 km. Similar investigations on the Furu fault are underway. It follows therefore that, according to Wells and Coppersmith (1994), the faults in the Dodoma area, assuming fully reactivation, can independently produce earthquakes of magnitudes ranging from about Ms = 6.95 to Mw = 7.20. |
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