Integration of Aeromagnetic Data and Landsat Imagery for Structural Analysis: A Case Study of Awgu in Enugu State, South-Eastern, Nigeria

• Authors: B. I. Ijeh , H. E. Ohaegbuchu , P. C. Okpetue
• Languages of publication: EN

Abstracts

EN

In this study, digital format data comprising of aeromagnetic and remotely sensed (Landsat ETM+7) data were used for structural interpretation of the Awgu area (predominantly underlain by sedimentary rocks) in Enugu State, southeastern part of Nigeria. Aeromagnetic data were analyzed using the Oasis Montaj 7.5 software and interpretation was carried out by applying the vertical and horizontal gradients, analytical signal, reduction to pole, tilt depth, as well as Euler deconvolution. The total magnetic intensity map shows a magnetic signature ranging from -39nT to 129nT. The 3D Euler solution of the study area has a structural index of 1.0 with dyke/fault as the shape of the inferred geological structure. In the Landsat ETM+7 satellite data used, band 5 was found as the most suitable in (automatic) delineation. The automatic lineament extraction process was carried out utilizing the line module of PCI Geomatica (2015 version). The essence of analysis and interpretation of the Landsat ETM+7 was to determine the lineament trends and density across the area. Rockworks 16 version software was used to generate the rose diagrams. As a result of the work, the aeromagnetic and Landsat lineament maps of the study area were summarized using rose diagrams. This revealed NE-SW as the major trend with some secondary trends NW-SE, E-W and N-S directions. However, the NE-SW trend reflects the younger tectonic events, because the younger events are more pronounced and tend to obliterate the older events. In a comparison of the aeromagnetic and Landsat lineament extraction of the study area in terms of number of lineaments, directions and total length of lineaments, the Landsat imagery were found to be better than the number, directions and total length of the aeromagnetic data.

Keywords

EN

Aeromagnetic data; Awgu; Landsat; remote sensing; structural analysis

Discipline

• GEOPHYSICS: GEOPHYSICS

• Publisher: Scientific Publishing House „DARWIN”
• Journal: World News of Natural Sciences
• Year: 2018
• Volume: 18
• Issue: 2
• Pages: 79-105

Contributors

author

B. I. Ijeh

• Department of Physics, College of Physical and Applied Sciences, Michael Okpara University of Agriculture, Umudike, Nigeria

author

H. E. Ohaegbuchu

• Department of Physics, College of Physical and Applied Sciences, Michael Okpara University of Agriculture, Umudike, Nigeria

author

P. C. Okpetue

• Department of Physics, College of Physical and Applied Sciences, Michael Okpara University of Agriculture, Umudike, Nigeria

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• Document Type: article