A threatening earthquake in SW Nigeria?

The increase in reports of tremors in the south-west Nigerian sub-region within the past two-three decades has become disturbing; and several research works (Elueze, 2003, Odeyemi, 2006, Anifowose et al., 2006, Kolawole & Anifowose, 2011) had referred to the Ifewara-Zungeru mega-structure and its connecting Southern-Atlantic transform faults as the major sources.

Below is a historical record of earth tremors in Nigeria (Akpan & Yakubu, 2010):

 

However, these questions may arise:

Considering the spatial coverage of the effects of the tremors, is it possible that these tremors were produced by more than a single fault (Ifewara Fault)? or are there possibly more active faults in the region?

 

I will like to know your thoughts on this issue. Kindly drop your opinions in the comment box.

   

References:

1. Akpan, O. U. and Yakubu, T. A. (2010). A review of earthquake occurrences and observations in Nigeria. Earthq Sci. (2010) 23. Pp. 289-294.

2. Anifowose, A. Y. B., Odeyemi, I. B. and Borode, A. M. (2006). The tectonic significance of the Ifewara-Zungeru megastructure in Nigeria. In: Teme S C and Ezeigbo C U. Proceedings of the 1st International Workshop on Geodesy and Geodynamics. Centre for Geodesy and Geodynamics, Toro, Nigeria. Pp. 17–28.

3. Elueze, A. A. (2003). Evaluation of the 7 March 2000 earth tremor in Ibadan area, southwestern Nigeria. Jour Min Geol 39(2). Pp. 79–83.

4. Kolawole, F. and Anifowose, A.Y.B. (2011). Remote sensing analysis of a dextral discontinuity along Ifewara-Zungeru area, Nigeria, West Africa. Ind. Jour. of Sci. & Tech. Vol. 4 No. 1. Pp. 46-51.

5. Odeyemi, I. B. (2006). The Ifewara fault in southwestern Nigeria: Its relationship with fracture zones along the Nigerian coast. Centre for Geodesy and Geodynamics, Toro, Bauchi State. Pp. 1–13.