Polarimetric SAR as a Tool for Remote Sensing Salt Diapirs, Axel Heiberg Island, Nunavut

• Main Author: Harrington, Elise M.
• Format: Text
• Language: English
• Published: Scholarship@Western 2018
• Subjects: Canadian Arctic; RADARSAT-2; spectroscopy; remote predictive geological mapping; gypsum; surface roughness; Geology; Arctic; Axel Heiberg Island; Canada; Heiberg; Nunavut
• Online Access: https://ir.lib.uwo.ca/etd/5321; https://ir.lib.uwo.ca/context/etd/article/7314/viewcontent/Harrington_Thesis_Rev3.pdf

The costs and hazards associated with traditional geological mapping have driven rapid advancement of remote predictive mapping techniques using satellite data. However, few studies have implemented synthetic aperture radar for geology. This study uses quad-polarimetric RADARSAT-2 and PALSAR-1 data to produce circular polarization ratio images over Axel Heiberg Island, Nunavut, Canada. These images are used to characterize the radar properties of gypsum and anhydrite diapirs and secondary salt deposits that have been mapped using visible and near infrared, short wave infrared, and thermal infrared spectroscopy. Diapiric salt outcrops appear rough in radar at the C-Band and L-Band (cm-dm) scales, whereas the secondary salts appear smooth. Ground truthing in the field confirms that salt diapirs are rough from millimeter to meter scale, whereas secondary salt minerals are precipitating on smoother surfaces, like floodplains and hillslopes. These results show that radar can be used to differentiate between diapiric and secondary salt exposures.