In the afternoon of January 30, 2017, the wide depression in the western part of the Dålk Glacier, East Antarctica, was formed. By coincidence, aerial surveying was carried out in this area, so it is possible to assess the extent of this catastrophic phenomenon. Aerial photos were taken on January 20 and February 9, 2017, respectively. Based on the photographic data, the size of the depression were 183 × 220 m, and its area reached 40.260 m². The depth of the depression in the early days was 20-30 meters; the maximum measured depth was 43 m. An approximate volume of the cavern was about 884, 013 m³. On preliminary conclusions, this event should be the similar jokulhlaups, when the water of Boulder Lake broke the icy border and rushed downstream under Dålk Glacier to Prudz Bay.