Land Behind Baghdad PDF Download

High-resolution low-cost declassified CORONA spy satellite imagery is used to detect archaeological sites and relict canals in the Diyala Plain to the east of Baghdad, Iraq. This project seeks to improve upon the ground survey conducted there in the 1950s by providing better geographic control and discovering sites and canals that were not included in the original survey. CORONA imagery provides a sub-2-meter spatial resolution and was acquired shortly after the original ground survey was conducted, providing an excellent medium for comparison. CORONA imagery is subject to significant spatial distortions because of its camera technology, and the LPS package for ERDAS Imagine was used for orthorectification. This procedure eliminates the need for camera ephemeris data or mathematical models and relies on ground control points. Google Earth was successfully used as the geographic reference. An attempt was also made to utilize the stereographic nature of the product to photogrammetrically extract digital elevation models, but low topographic relief and poor image contrast contributed to poor results. The highly accurate orthorectified images were then visually inspected for evidence of archaeological sites and relict canals. A total of 655 sites were found in the study area, essentially doubling the number of sites found in the ground survey, although this number likely underrepresents the actual number of sites present on the landscape due to difficulty in distinguishing some features. The sites found generally were smaller in area than those in the ground survey, establishing CORONA's utility for finding sites difficult to detect on the ground. The canal network of the original survey was also greatly extended. The usefulness of CORONA as a tool for archaeological survey is amply demonstrated, although some refinements will be required in establishing the distinguishing characteristics of sites before it can be used in lieu of ground-based survey.