Lineament Extraction using Landsat 8 (OLI) in Gedo, Somalia

Lineaments are linear features which provide information about the underlying geological structure. Their analysis are widely considered in the location or siting of suitable groundwater exploration sites since the water will tend to flow along the fracture zones. The papers major objective was to extract the lineaments in Gedo Region in southern Somalia, with a view of using the analysis for groundwater exploration in the future to mitigate the frequent droughts in the area. The analysis was carried out using Band 7 of Landsat 8 (OLI), which was automatically processed using the Lineament Extraction (LINE) module of PCI Geomatica to extract the lineaments in the region. These were then verified using sobel filtered images in the four cardinal directions and manually digitized lineaments from a geological map partly covering the region and false colour composites of the study area. The results showed that the automatic extraction of lineaments using LINE can yield tangible results using optical imagery. However, the lineaments still require verification through comparison with known lineaments. Directional filtering of Band 7 of Landsat 8 proved to be useful in visual identification and verification of lineaments.