Delineation of Hydrothermally Altered Zones that Favour Gold Mineralization in Isanlu Area, Nigeria Using Aeroradiometric Data

Ohi Jerry Ohioma; Friday Ezomo; Akinniyi Akinsunmade

doi:10.21467/ias.2.1.20-27

Authors

Ohi Jerry Ohioma Department of Physics, University of Benin
Friday Ezomo Department of Physics, University of Benin
Akinniyi Akinsunmade Nigerian Geological Survey Agency

DOI:

https://doi.org/10.21467/ias.2.1.20-27

Abstract

Aeroradiometric data set of Isanlu sheet 225 (1:100,000) has been acquired with a view to analyze and interpret for the delineation of hydrothermally altered zones that favour gold mineralization. The acquired aero-radiometric data was subjected to filtering algorithm and enhancement techniques such as shaded relief enhancement, elemental ratio enhancement using Geosoft Oasis Montaj Software. Moreover, Golden Software Surfer was used to identify and present the revealed hydrothermally altered zones. The interpretation of the aero data set has enhanced the delineation of eight hydrothermally altered zones. Therefore, the areas that are hydrothermally altered are potential sites for gold mineralization, such as areas around Odogbe and Okolom in the north-central portion of the study area. Similarly, regions around Egbe in the western edge are suspected to be mineralized zones. Results obtained in this research study have shown that mapping of hydrothermally altered zones that favour gold mineralization is feasible even without the actual physical contact and visitation to the area. The research suggests that this method of delineation may compliment other geophysical exploration technique for possible gold bearing zones of an area. Moreover, due to the non-invasive nature of the method, large areas of space may be mapped within a limited time. Areas that are non-accessible to ground geophysical exploration due to various factors can also be studied.

Keywords:

aeroradiometric data, gold mineralisation, hydrothermal alteration, Isanlu sheet 225

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