Application of Euler and Werner deconvolution techniques in delineating tin deposit in Okeso area, Southwestern, Nigeria
Date
2024
Journal Title
Journal ISSN
Volume Title
Publisher
Nigerian Society of Physical Sciences
Abstract
The Okeso pegmatites field was evaluated using magnetic method within abandoned mining site close to the southeastern region of
Ojoku area. The study aims to delineate, identify geological boundaries and determine depth of tin deposits in the area. The acquired
magnetic data was enhanced with the combination of 3D Euler and Werner deconvolution methods. Five magnetic profiles were
selected and carried out on the residual anomalies around the abandoned mine site at Okeso with three of the profile lines were in
the NW-SE direction and two in the NE-SW direction. The residual magnetic anomalies showed the magnetic susceptibilities of
≤ 4.5118 × 10−3 nT in the ore bearing pegmatite within the basement rocks. Results from profiles of Werner deconvolution identified
some shallow tectonic structures like fractures, pegmatites and faults which are capable of hosting metallic tin deposits. The depth
to the magnetic source varies from a minimum to a maximum of 300 m to 1200 m below the subsurface in all selected profiles,
suggesting the shallow nature of the magnetic source in the area. Additionally, the dip angle ranges from 5.60 to 81.20, potentially
attributed to Pan-African shallow structures according to the contact model. Solutions obtained from the structural index of contact
and dyke reveals the presence of dyke formation and boundaries which separate rocks from one another. The trend of the lineaments/
fractures which were likely established during the Pan-African orogeny is dominant in the NE-SW direction, conforms with the
trends obtained for basement structures in previous studies. Depth range produced by 3D Euler deconvolution is from 50 - 1000 m
for all the lineaments. This gives an insight of approximate depth range of all the lineaments/ fractures across the whole map in the
study area unlike, Werner deconvolution which is profile biased. The identical signature from all profiles implies that the tin deposit
is relatively uniform, extending to a great depth in the area. This represents economically viable quantity and makes it a worthy target
for investors.