This is a case-study that compares the application of Landsat ETM+ and IKONOS imagery when assessing a natural terrain's susceptibility to landslides. This study looked at six areas located in the upland areas of Nepal and Bhutan. In each case, the imagery has been used both to directly map landslides and to examine the occurrence of factors that might be important in landslide initiation, such as water seepage. The results from the imagery were bench-marked using field surveys.
The results of this study demonstrated that Landsat ETM+ continues to be the most cost-effective imagery tool for mapping landslide susceptibility. This is due to the fact that it is relatively low-cost and has high spectral resolution. However, the researchers state that the spatial resolution is still a significant limitation to Landsat ETM+.
The high resolution, multispectral IKONOS imagery is not limited in the same way. With IKONOS, even small landslides are able to be mapped in great detail. However, according to the report, this type of imagery is less useful for factor type mapping. The report concluded that of the high cost of IKONOS will prevent most developing countries from developing and utilizing the tool, resulting in Landsat ETM+ being the better tool for mapping landslide susceptibility.