Mapping faults around Adama Town: Implication for future earthquake triggering potential

Abstract

The unique structural and morphological feature of Adama area studied to infer local paleo-stress direction and to further evaluate their earthquake triggering potential. Kinematic analysis on standard field based structural data performed and integrated with geomorphological results. N 112⁰ E directed stress inferred from kinematic analysis technique. The result is statistically similar with the current stress inferred from geophysical monitoring (~ N 105⁰ E) .The result shows minor deflection to the south. This deflection could be resulted due to crustal strength heterogeneity and /or local stress change. Morphological analysis using stream profile index indicate active fault signatures .These signatures are mainly common in the west of the study area. Integration of structural and geomorphological data mainly from the western side of the town further confirms active fault characteristics. Pilot study on ground cracks around the town shows a significant relationship with faults of the area. This correlation indicate the current tectonic stress of the area has a significant control on the frequently occurring ground cracks in the area