The 2017 catastrophic subsidence in the Dålk Glacier: Unmanned aerial survey and digital terrain analysis

• Main Authors: Florinsky, Igor V, Bliakharskii, Dmitrii, Popov, Sergei, Pryakhin, Sergei
• Format: Other/Unknown Material
• Language: unknown
• Published: PeerJ 2018
• Subjects: Dålk Glacier; East Antarctica; Antarc*; Antarctica
• Online Access: http://dx.doi.org/10.7287/peerj.preprints.27064; https://peerj.com/preprints/27064.pdf; https://peerj.com/preprints/27064.xml; https://peerj.com/preprints/27064.html

We present the first results from a study of the 2017 catastrophic subsidence in the Dålk Glacier, East Antarctica using an unmanned aerial system (UAS) and UAS-derived DEMs. The subsided portion of the Dålk Glacier and adjacent territory was surveyed in two flights, before and after the collapse. The survey was performed by Geoscan 201, a small flying-wing UAS. Aerial images have an average resolution of 6 cm. Using Agisoft PhotoScan software, we generated two DEMs with a resolution of 22 cm related to the pre- and post-collapsed glacier surface. To model the pre-collapsed subglacial cavern, one DEM was subtracted from the other. Finally, we discuss a probable mechanism of the catastrophic subsidence.