By Toba Adedeji, Osogbo
Earth-tremor of low magnitude has rocked Omu-Aran, the headquarters of Irepodun Local Government Area in Kwara State.
A document obtained by The Nation on Monday dated 6th June 2021 by the Department of Geophysics, Obafemi Awolowo University, Ile-Ife, Osun State stated the earth tremor occurred on Saturday 5th, June 2021.
Professor Adepelumi Abraham, who signed the document titled: “Preliminary report on the 5th June, 2021 Earth-Tremor recorded at the Obafemi Awolowo University, Ile-Ife Osun State, Nigeria”, reports that “An earth-tremor of low magnitude occurred in Nigeria at 11:11:25.6 am (GMT) on 5th June, 2021. The origin time is 11:11.08.2 am (GMT) (Figures 1 to 3).
“The estimated epicentral distance (D) is placed between 108 and 113 km away from the measuring station at the Obafemi Awolowo University, Ile-Ife, Nigeria.
“The S wave particle motion generally trends N – S and NE – SW (Figure 4). This suggests that the wave is traveling perpendicular to the particle motion. Hence, the epicenter is somewhere along the NW-SE direction of Ile-Ife, Osun State, Nigeria.
“Using Single Station, the epicenter is roughly place closed to Omu-Aran Kwara State at Latitude (Y) 8o 06’18.0’ N, and Longitude (X) 4o 59’20.4’ E (Figures 5 to 7).
“The estimated focal depth is 15.0 km.
“The Moment magnitude (Mw) is 2.6 on the Richter scale.
“The Local magnitude (ML) is 2.4 on the Richter scale.
“A normal fault mechanism along the Ifewara-Zungeru Transcurrent Fault system due to INTRAPLATE SEISMICITY was deduced. This suggests that this fault system is still active.
“The fault that caused the Earth-tremor has a Stress drop of 5.9 bar.”