Project Abstract

Abstract
This research project focuses on the remote sensing analysis of the Ifewara-Zungeru megalineament in Nigeria. The Ifewara-Zungeru megalineament is a prominent geological feature in Nigeria with significant implications for tectonic and geodynamic studies. Remote sensing techniques offer a valuable tool for studying large-scale geological structures, and in this study, satellite images and digital elevation models are utilized to analyze the characteristics and implications of the Ifewara-Zungeru megalineament. The objectives of this research include mapping the megalineament using remote sensing data, analyzing its structural characteristics, and investigating potential correlations with seismicity and mineral resources in the region. By employing image processing and GIS techniques, the megalineament's orientation, dimensions, and associated features are delineated and quantitatively assessed. Furthermore, the relationship between the megalineament and known seismic activity in the region is explored to understand its potential influence on seismic hazards. The findings of this study reveal the detailed mapping of the Ifewara-Zungeru megalineament and its structural attributes, such as fault patterns, lineament density, and spatial relationships with geological units. The results suggest that the megalineament exhibits a complex structural evolution, likely influenced by regional tectonic processes. Additionally, the analysis indicates a correlation between the megalineament and seismicity, highlighting its importance in assessing seismic hazards in the region. Moreover, the remote sensing analysis identifies potential mineral resource indicators associated with the megalineament, suggesting its significance for mineral exploration efforts. By integrating geological, geophysical, and remote sensing data, this study contributes to a better understanding of the Ifewara-Zungeru megalineament's geodynamic context and its implications for natural hazards and resource exploration in Nigeria. Overall, this research underscores the importance of remote sensing techniques in studying large-scale geological features and highlights the significance of the Ifewara-Zungeru megalineament in the tectonic framework of Nigeria. The detailed analysis presented in this study provides valuable insights for future research on regional geology, seismic risk assessment, and mineral exploration in the study area.

Project Overview

The Precambrian basement complex of Nigeria as an integral part of the west African craton  is known to have been subjected to various episode of deformation. These activities reflect in the presence of geological structures like folds, foliations and fractures of varying magnitudes. Remote sensing can be applied in the study of regional structures particularly those that extend over hundreds of kilometers. One of such megastructures is the Ife Wara-Zungeru fault which extends in the western and northern parts if Nigeria. The magnitude of the fault and its extent over a complex litho-structural terrain make the area a good subject of study.
1.1  OBJECTIVES
The following are the objectives for carrying out this study;
a)     To identify and analyse lineaments over the study area.
b)     To establish the continuity of the lineaments on the southern and northern parts of the Nupe basin.
c)     To compare the effectiveness of different remotely sensed images in detecting and interpreting lineaments.
d)     T o evolve a model on the tectonic evolution of the Ifewara-Zungeru megalineament.                  
1.2   AREA OF STUDY
The area of study lies on the western half of Nigeria bounded by longitudes 4030’E to 7030’E, and latitudes 7000’N to 11000’N. An area bounded by longitudes 6000’E to 7030’E and latitudes10000’N to 11000’ was included to investigate the continuity or otherwise of the fracture zone. The study area is underlain by Precambrian basement complex rocks and a part of the cretaceous Nupe Basin. Prominent in the area are the Idanre hills and Efon ridges which extend northwards to Oke Onigbin ridges and Kisheriki hills in north central Nigeria. These hills serve as catchment and sources for the rivers that drain the area. The Osun, Owena, Ogbese and Ose rivers flow southwards into the atlantic ocean while the Asa, Oyi and Oro rivers flow northwards into the river Niger. Rivers Koriga and Sarkin Pawa drain into the Kaduna river which in turn empties into the river Niger. The study area is covered by various vegetation types ranging from rain forest in the south, through Guinea savanna to sudan savanna characterized by grassland with scattered shrubs in the north. A few forest reserves dot some parts of the southern area. Some major towns in the study area include Akure, Ibadan, ilesa, Ilorin, jebba, Kaduna, minna, mokwa, osogbo and zunger.
1.3  PREVIOUS WORK
Although the basement complex rocks in the western half of Nigeria have been studied through geological mapping very little work has been done using remote sensing. The schist belts in particular have received a lot of attention apparently due to its complex nature and mineralization. It has been known to consist of low to medium grade schists, metaconglomerate, quartzites, calc silicate gneises, banded-iron formation, amphibolites and other meta-igneous rocks ( Truswell and Cope, 1963; McCurry, 1976; Rahaman, 1973, 1976; Turner, 1983; Odeyemi, 1976,1977,1988,1988;Adekoya, 1993). In addition, prominent workers have studied other parts of the basement complex (Hubbard, 1975; Odeyemi, 1981; Fitches et al., 1985; Braide, 1992; Okonkwo, 1992). The geology and structural disposition of rocks in the Ilesha schist belt have been earlier studied and various evolution models have been suggested ( Elueze; 1977; Odeyemi, 1981; Ajibade, 1976; 1982; Turner, 1983; Ajibade et al, 1986; Ananaba and Ajakaiye, 1987). For example, Hubbard (1975) first recognized a major NNE-SSW trending Ifewara fault that separates the rocks of Ilesha schist belt into two structural units with contrasting lithologies. Geophysical methods have also been employes in the study of this area. Ako et al, (1978) first established a lithostructural break among the rock units, but ascribed it to silicification which itself is indicative of healing along a fault zone.
Olasehinde et al. (1990) studied aeromagnetic anomalies and their correlation with some lineaments in the basement complex of Nigeria. Folami (1992) also carried out aeromagnetics mapping over a part of the Ilesha schist belt. Results of the study show the presence of a continuous structure which trend and location agree with the Ifewara fault earlier recognized by hubbard (1975). Idornigie and Olorunfemi (1992) carried out geoelectrical survey which indicates a high degree of the Nupe Basin. Also, two sets of fault trending along the NW-SE and NE-SW directions were recognized. A regional aeromagnetic mapping of crustal lineaments was carried out by Ananaba (1991) in an attempt to assess the possible risks of dam failure in Nigeria. A lineament study of northern Nigeria using landsat images was carried out by Ananaba and Ajakaiye (1987) to correlate lineament density with mineral occurrences, results of the study suggest that primary mineralization in Nigeria is tectonically controlled.
1.4 JUSTIFICATION FOR THE STUDY
None of the previous works in the study area was aimed at establishing the regional continuity of any particular structural feature by combining satellite-based and aircraft-based data sources for a study. Therefore this effort is focused at studying the Ifewara-Zungeru megalineament through a combination of many remote sensing techniques. Such a study would provide more information on the Precambrian evolution, tectonics as well as mineral and energy resources within the study area. In addition, the results can be useful in mineral exploration since the presence and types of minerals depends on geologic antecedents along the megalinear. This is the reason for choosing this trend of study.  

REFERENCE
AJIBADE, A.C. 1976. Provisional classification and correlation of the schist belts of northwestern Nigeria. In; C.A. Kogbe(ed.), Geology of Nigeria, Elizabethan Publishing Co., Lagos, pp. 85-90
AJIBADE, A.C., WOAKES, M. and RAHAMAN, M.A. 1986. Proterozoic crustal development in the Pan-African regime of Nigeria. Amer Geophy. Union, pp 259-271
AKO, B.D., AJAYI, T.R. and ALABI, A.O. 1978. A geoelectrical study of the ifewara area. Jour.Min.Geol.Vol. 15, No. 2, pp84-89
ANANABA, S.E. and AJAKAIYE, D.E. 1987.E vidence of tectonic control of mineralization in Nigeria from lineament density analysis. Inter. Jour. Rem. Sens. Vol. 8, No. 10, pp 1445-1453
BRAIDE, S.P. 1992. Geological development, origin and energy mineral resources potential of the Lokoja Formation in the southern Nupe Basin. Jour.Min.Geol.Vol.28, No. 1, pp.33-34
ELUEZE, A.A. 1977.Geological and geochemical studies in the Ife-Ilesa schist belt in relation to gold mineralization in Nigerian schist Belts. Jour.Min.Geol. Vol.18,No 1,pp 31-36
FITCHES, W.R., AJIBADE, A.C, EGBUNIWE, I.E., HOLT, R.W. and WRIGHT, J.B. 1985. Late Proterozoic schist belts and plutonism in Nigeria. Jour. Geol. Soc. Lond. Vol. 142, pp. 319-337