Evidences by Multiscale Analysis and 2D3/4 Models from the Magnetic Anomalies and Iron Mineralization (BIF) over the DJADOM-ETA Area, Southeastern Cameroon

Justine Yandjimain,Paul Claude Ngoumou,Théophile Ndougsa-Mbarga,Arsène Meying

doi:10.4236/ojer.2020.91002

Abstract

The Magnetic method is one of the best geophysical techniques used to delineate subsurface structures. This study was conducted to investigate the basement faulting and ore mineralization into the overlying geological cover. The GEOSOFT v8.4 software was used to process the data. Upward continuation of the residual magnetic intensity map at various altitudes and the maxima of their horizontal gradient magnetic were used to highlight faults from shallow to deep, as well as, their dips and mineralization zones. The faults with the directions E-W, ESE-WNW and ENE-WSW are identified confirming the result of [1]. This study also reveals that, the layer is affected by faults propagating from the basement upwards into the cover. Our results added additional information to the knowledge of the geological structure and the mineral resources potential in the study area. Based on the 2D3/4 modeling, the Dja Fault (DF) is revealed and highlighted sub-area marked by a magnetite/or hematite dolerite, schist and sandstone blocks, which show strong magnetization. Specifically, in this area, models are made of BIF (bounded iron formation) and BIQ (bounded iron quartzite) as dominant minerals.

Highlights

Cameroon is underlain by Precambrian rocks, Cretaceous and Cenozoic sediments and volcanic formations [2]
This study reveals that, the layer is affected by faults propagating from the basement upwards into the cover
The main fault on Djadom axis is interpreted as an intersected lineament and those on the Eta axis represented by an entrainment lineament

Summary

Introduction

Cameroon is underlain by Precambrian rocks, Cretaceous and Cenozoic sediments and volcanic formations [2]. Cameroon in general and its south-eastern area are a zone where geological and geophysical investigations are carried out permanently. The purpose of this study is to highlight some sub-zone of mineralization and the basement structural system with the use of the HMG maxima method applied to aeromagnetic data. Aeromagnetic survey maps showing variations of the geomagnetic field and magnetic anomalies are interpreted to be a function of the rock’s magnetization. This observation is often explained using magnetic profiles and maps of magnetic lineaments [4]. The magnetic investigation done by [1] is used the tilt angle method and has highlighted two major lineaments: ESE-WNW and ENE-WSW.

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Discussion

Conclusion