Archaeologists have used high-resolution satellite images in the visual spectrum to identify numerous archaeological sites. This work has been most productive in desert areas, where ground cover is scarce or lacking. Archaeologists working on the Pacific Coast of South America, especially Peru, and in the Sahara, especially Egypt, have used images from such systems as Google Earth to identify sites, especially those with built structures, that are worthy of further exploration.
However, there is much in the archaeological record that is not as apparent in the visual spectrum as buildings. Humans in the past have wrought changes in the earth’s surface through activities like cultivating fields, digging irrigation ditches, creating earthen mounds for burial or religious purposes. Evidence of such activities is not usually visible in visible-spectrum observation, but infra-red and near infra-red may reveal current and past patterns of vegetation that reflect past human activity.
My project with the Yale Center for Earth Observation will be to explore ways in which satellite data can be used to support research in archaeology. My hope is that my research will go beyond identifying man-made features and that it will permit analysis of features and groups of features. That research might, for example, identify regions and ecological zones most likely to have supported human settlement in the past.
Another piece of my work will be to attempt an analysis of data from geomagnetic satellites (the Oerstad and Magsat satellites) to understand changes over time and anomalies in the Earth’s magnetic field. Archaeologists have been establishing curves of the changing position of the Earth’s magnetic pole and local variations in the magnetic field. Those curves, created from terrestrial observations and the analysis of burned earthen materials are useful in dating such archaeological remains as hearths and metallurgical furnaces. Understanding satellite observations of the earth’s magnetic field could support and refine the analysis derived from terrestrial magnetic observations.