Possibilities of Archaeological Prospection by High-resolution X-band Satellite Radar – a Case Study from Syria R. LINCK 1,2 * , T. BUSCHE 3 , S. BUCKREUSS 3 , J. W. E. FASSBINDER 1,2 AND S. SEREN 4 1 Bavarian State Department for Monuments and Sites, Ref. ZII Archaeological Prospection, Hofgraben 4, 80539 Munich, Germany 2 Department of Earth and Environmental Sciences, Geophysics, Ludwig-Maximilians-University, Theresienstr. 41, 80333 Munich, Germany 3 German Aerospace Centre, Microwaves and Radar Institute, Muenchner Straße 20, 82234 Wessling, Germany 4 Central Institute for Meteorology and Geodynamics, Hohe Warte 38, 1190 Vienna, Austria ABSTRACT The launch of the first German radar satellite TerraSAR-X in 2007 opened a new era in spaceborne radar remote sensing. So far the applicability for the high-resolution prospection of upstanding and, especially, buried monuments was limited because of the low resolution of the former sensors. TerraSAR-X, however, provides us with images with a spatial resolution of up to 1 m. The satellite operates in the so-called X-band with a frequency of 9.65 GHz. Therefore it is supposed that there is no possibility to penetrate the soil with this sensor. To testify and analyse the benefit of TerraSAR-X in archaeological geophysics, we chose as a test site a Roman fortress in Syria. The site was chosen as we already have GPR data of the same area for a comparison and for the verification of the actual penetration depth. Our results revealed that it is possible to resolve superficial and even buried structures in the data set, which provides evidence that the X-band waves can penetrate the soil. This paper shows our results of the survey and an estimation of the possible penetration depth of TerraSAR-X. Copyright © 2013 John Wiley & Sons, Ltd. Key words: synthetic aperture radar; SAR; TerraSAR-X; ground-penetrating radar; GPR; Syria; Roman Introduction First attempts to use SAR data for archaeological prospection were made only a few years after the launch of the first SAR satellites. Old irrigation chan- nels and cultivated wetlands of the Mayas on the Yucatán peninsular were detected with SEASAT data (Adams, 1980, 1982; Adams et al., 1981; Pope and Dahlin, 1989; Sever, 1998). Also in the arid regions of the Earth, early SAR studies were accomplished. For example, McCauley et al. (1982) succeeded in proving a 2-m-deep Pleistocene drainage system in the Sahara by SIR-A radar images. The same sensor was used to detect an old river system buried under the desert (Walker, 1982; Holcomb, 1990, 1992, 1993; Holcomb and Allan, 1992). As a result of the limited spatial resolution of his data sets, Blom (1992) could only detect the lost town of Ubar (Oman) by the conver- gence of several roads, but not directly by distinct buildings. Furthermore the Canadian RADARSAT missions were used for archaeological research, for example to survey settlements and river systems by Richason and Hritz (1998). New research results on the archaeological prospection with SAR have been gained in Italy (Piro et al., 2011), Iraq and Sudan (Patruno et al., 2012) and Italy and North Africa (Stewart et al., 2012). The main problem for all these attempts was the limited resolution of the sensors, which was in the order *Correspondence to: R. Linck, Bavarian State Dept. of Monuments and Sites, Archaeological Prospection, Hofgraben 4, 80539 Munich, Germany. E-mail: roland.linck@blfd.bayern.de Copyright © 2013 John Wiley & Sons, Ltd. Received 3 January 2013 Accepted 19 March 2013 Archaeological Prospection Archaeol. Prospect. 20, 97–108 (2013) Published online 6 May 2013 in Wiley Online Library (wileyonlinelibrary.com) DOI: 10.1002/arp.1444