Change Detection of Geomorphic Units of Mighan Basin Using Multi-Temporal Satellite Data

Remote sensing technology is the key to identify changes of geomorphic units. Mapping and detection of changes is one of the main elements of projects related to land capability. In this paper changes of geomorphic units within the study area will be detected in period of 30 years. To achieve the goals of this research the digital images of MSS(5 Sep., 1972), TM (8 Sep., 1990)and ETM+ (25 July, 2002) ,topographicand geological maps and field observations were used. The three multi-source images were geometrically and radio metrically calibrated to each other and thenthe best false color composite (FFC) was prepared based on Jeffries matusita and PCA index( 742 ,741 for ETM, TM images and 431 for MSS image). In continueafter doing linear stretch on images, geomorphic maps were prepared based on supervised classification. The overall accuracy of the maps was equal to 83.65 (MSS), 86% (TM) and 63% (ETM+). Based on obtained resultsstudy area’s geomorphic units consist of clay flats, salt flats, Fans, alluvialterracesand vegetation cover. For change detection of study area’s geomorphic units post- classification comparison was used. Investigation of the trend of changes indicates during 30 years (1972-2002) some geomorphic units ( Fan andterrace lands) have increased from2127.56 to 2848 square kilometers.Salt flathas increasedfrom125.8 to 469.8km?? ,while rest of the units (vegetation cover) decreaseddue toclimate and land use changes.