Submarine landslides on the Crary Trough Mouth Fan, Antarctica.
Presented by Ms. Jenny GALES on 23 Sep 2013 from 17:15 to 19:15
Type: Poster presentation
Session: Poster session
New multibeam bathymetric data from the southeastern Weddell Sea reveal three large-scale submarine slides on the upper slope of the Crary Fan, a trough mouth fan offshore from the glacially carved Filchner Trough. All slides head at the shelf edge (~500 m water depth), with the largest slide measuring 20 km wide and with an incision depth of 60 m. Multibeam and seismic data show elongate slide blocks on the seafloor surface of the mid-slope. The lack of a discernible sedimentary cover suggests that they were generated after the Last Glacial Maximum (LGM). This is unusual because post-LGM submarine slides are very rare on the Antarctic continental margin, and to our knowledge, no other Late Quaternary slides have been documented on an Antarctic trough mouth fan. This contrasts many other previously glaciated high-latitude continental margins, where submarine landslides are common. The large-scale differences in landslide occurrence between the Crary Fan and other Antarctic margins suggest a significant variation in slope and sedimentary processes, environmental characteristics and/or glacial dynamics between these regions. We speculate that weaker, unconsolidated sedimentary layers within the subsurface are important for slide initiation here.
Location: GEOMAR East shore
Address: Wischhofstr. 1-3 / D-24148 Kiel