Lineaments on Landsat Images-detection Mapping and Tectonic Significance in North –western Depressions of Syria

The objective of this investigation was to determine the feasibility of mapping lineaments on Landsat images of ElRouge, and Al-Ghab depressions, north-west of Syria, and to determine the tectonic significance of these lineaments in order to evaluate the capabilities and limitations of spaceborne data to prove that El-Rouge depression is the extension of Al-Ghab depression and both of them in line with the African-Lebanon-Syrian rift system. The depressions are situated in the marginal part of the Arabian platform in the zone of the rift system. The investigations were carried out on the basis of multispectral data of Landsat-5 Thematic Mapper. Regional analysis of the images allows rapid evaluation of the structures. The surface expression of lineaments have been mapped and analyzed in terms of their style of deformation, thickness, size and potential influence. Digital masking was used to eliminate ambiguities due to water and shadows. Contrast Enhancement, involves a contrast stretch of the row digital information, and band rationing have been shown to be a useful tool for mapping structural unites and minimized the differences in illumination due to topographic slope changes. Principal components analysis has been utilized in statistical processing of data. The method produces new variables which are linear combinations of the original variables. Field identifications have been carried out to judge the effectiveness of the different spectral bands and of the digital processing of the data.