SPATIAL ANALYSIS AND MAPPING OF BITUMEN LOCATION IN OKITIPUPA LOCAL GOVERNMENT AREA OF ONDO STATE.

Abstract

Recently various private investors have shown interest in the exploitation of bitumen in Ondo State, but were faced with some problems such as no adequate information about the geographical locations and distribution of bitumen deposit in the study area, also, getting hold of the information about the environmental impact assessment of the study area proved abortive, finally, physical and chemical properties of bitumen in the study area has not been carried out, hence making it difficult to assess if it’s of economic relevance. Bitumen is a viscous liquid or solid made primarily of hydrocarbons, it can be obtained by refining petroleum, or can be discovered as a natural deposit or as a component of naturally occurring asphalt. (Alagbe, 2020). Agricultural and farming activities have been immensely affected due to damages caused by oil spillage from up stream flow down to Agric settlements. Settlers in these places have been living under unhealthy life style especially during the raining season. Spatial analysis and mapping of bitumen locations is carried out in order to determine areas affected and areas prone to hazard using remote sensing and GIS technique. The objective of the research is to examine the geographical extent of bitumen locations in the study area, Assess the hazard effects of bitumen in the study area, and evaluate the economic significant of bitumen in the study area. Differential Global Position System was used to acquire the coordinate of bitumen locations in the study area. The coordinate was later used in downloading the Shuttle Radar Topography Mission (SRTM), SRTM Digital Elevation Model from USGS which was used for flow accumulation, flow direction and stream ordering analysis as well as visualizing and assessing the conditions for spill from bitumen location to different settlements. The assessment of the hazardous effects of bitumen in the study area was carried out using hydrological analysis method and Mathematical embedded model in ArcGIS10.2 (Getis-ordGi). Landsat Thematic Mapper of year 2020 was used to determine the land cover of the study area in other to depict affected built up area, vegetation, bare surface, and water bodies. Bulk density, porosity, electrical resistivity, and x-ray florescence test was carried out on the collected sample to determine their physical and chemical component which assisted in the assessment of the economic relevance of the collected samples. The total area covered was 87549.98ha, out of which 5.269% was bare surface, built up area takes 9.406%, vegetation takes 77.334% and water body takes 2.836%. The analysis also shows that 1.17% of bare surface is affected, 2.430% of built up area, 6.198% of vegetation and 1.384% of water body are also affected by the bitumen. The research reveals that villages such as Igodan-Lisa, Ago Bonema, Oluagbo, Igbo Ayeka, Okitipupa, Erinje-Ekeji, Epinnipinni, Igbotako-Erinje, Ago Woli, Igbobini, Odole are affected by bitumen spillage while Jemidudu is liable to spillage of bitumen. The study revealed that there is abundance of bitumen deposit in the study area, hydrological analysis as well as land use land cover showed that larger percentage of the affected area is vegetation and forested covers followed by built up and smaller percentage of water body, The chemical analysis of the bitumen from the study area is averagely consistent as compared to other localities. The results confirmed that the bitumen sample analyzed is rich in silica (SiO2) and alumina Al2O3) which indicates that it is of high economic relevance. It was however recommended that this research work should serve as a guide in curbing area that are affected and also area prone to bitumen hazard before it escalates further so as to protect lives, properties, and natural habitats. The government of the day should also create a political enabling environment for bitumen exploitation.