<abstract xmlns="http://www.w3.org/1999/xhtml"><p> The Onigbedu limestone deposit was investigated using the aeromagnetic data, resistivity soundings and borings with the aim of characterizing the limestone deposit and estimating its reserves. The subsurface structural features and depth to basement were identified with the analysis of aeromagnetic data. Twenty nine boreholes were drilled for subsurface appraisal and correlation of the limestone deposit. Eighty nine Vertical Electrical Sounding (VES) were acquired using the Schlumberger array. The results showed NE-SW trending lineaments that segmented the limestone. Depth to basement varied from 144.2 m to 1090 m. The VES results showed four to six layers indicating the topsoil (7-315 Ωm), clay (2-25 Ωm), shale (6-31 Ωm), limestone (20-223 Ωm), sandstone (>200 Ωm) and sandy materials. The VES results correlated well with the lithological unit delineated from the borehole. The overburden thickness ranged from 3.3 m to 28 m, while the limestone thickness varies between 18.1 m and 48.3 m. The limestone reserve was estimated at 1.9 × 10<sup>9</sup> t. This study concluded that the study area had vast occurrence of the limestone deposits, which would be of economic importance, if exploited.</p></abstract>

The Onigbedu limestone deposit was investigated using the aeromagnetic data, resistivity soundings and borings with the aim of characterizing the limestone deposit and estimating its reserves. The subsurface structural features and depth to basement were identified with the analysis of aeromagnetic data. Twenty nine boreholes were drilled for subsurface appraisal and correlation of the limestone deposit. Eighty nine Vertical Electrical Sounding (VES) were acquired using the Schlumberger array. The results showed NE-SW trending lineaments that segmented the limestone. Depth to basement varied from 144.2 m to 1090 m. The VES results showed four to six layers indicating the topsoil (7-315 Ωm), clay (2-25 Ωm), shale (6-31 Ωm), limestone (20-223 Ωm), sandstone (>200 Ωm) and sandy materials. The VES results correlated well with the lithological unit delineated from the borehole. The overburden thickness ranged from 3.3 m to 28 m, while the limestone thickness varies between 18.1 m and 48.3 m. The limestone reserve was estimated at 1.9 × 109 t. This study concluded that the study area had vast occurrence of the limestone deposits, which would be of economic importance, if exploited.

Exploration for limestone deposit at Onigbedu, South–Western Nigeria

University of Lagos, Department of Geosciences, Lagos,

Materials and Geoenvironment

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

{"article-title":"Exploration for limestone deposit at Onigbedu, South\u2013Western Nigeria"}

The Onigbedu limestone deposit was investigated using the aeromagnetic data, resistivity soundings and borings with the aim of characterizing the limestone...

Exploration for limestone deposit at Onigbedu, South–Western Nigeria

Published Online: Dec 13, 2016

Page range: 139 - 150

Received: Nov 11, 2015

Accepted: Jun 15, 2016

DOI: https://doi.org/10.1515/rmzmag-2016-0013

Keywords
limestone, aeromagnetic, resistivity, boring, tonnage, overburden

© 2016

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Exploration for limestone deposit at Onigbedu, South–Western Nigeria

Published Online: Dec 13, 2016

Page range: 139 - 150

Received: Nov 11, 2015

Accepted: Jun 15, 2016

DOI: https://doi.org/10.1515/rmzmag-2016-0013

Keywordslimestone, aeromagnetic, resistivity, boring, tonnage, overburden

© 2016

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Keywords
limestone, aeromagnetic, resistivity, boring, tonnage, overburden