Susumu Ogawa1* and Katsuya Takaku2
1Graduate School of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan
2Graduate School of Environmental Life Science, Faculty of Environmental Information Science, Yokohama National University, 79-1 Tokiwadai, Hodogaya District, Yokohama, Kanagawa 240-8501, Japan
*E-mail address: ogawasusumu@nagasaki-u.ac.jp
(Received March 31, 2012; Accepted July 11, 2012)
Abstract. In this study, our aim was identification of relationship between the Nazca lines and groundwater flow with a satellite image. The lines were extracted from an ALOS/PRISM image as bright and dark lines with the maximum likelihood procedure. Next, extracted images were checked up with ALOS/PALSAR and SRTM-3 topographic data, which show the groundwater flow. Then, a part of the biggest geometric configuration was shown with groundwater flow. The lines coincided with the groundwater flow, while the pictures indicated the locations of seepage from the groundwater. The groundwater was the most important for the ancient Nazca agriculture and the lines would relate with it.
Keywords: ALOS, Binarization, Nazca Lines, Seepage, SRTM-3