Characteristics and distribution of submarine canyon-related landslides in Shenhu area, northern South China Sea margin
Presented by Mr. Zenggui KUANG, Prof. Liaoliang WANG, Prof. Yiqun GUO on 23 Sep 2013 from 17:15 to 19:15
Type: Poster presentation
Session: Poster session
High-resolution 2-D multichannel seismic data, combined with high-precision multibeam bathymetric relief map, were utilized to investigate the characteristics and distribution of submarine landslides in Shenhu area in the upper slope of northern South China Sea (SCS) margin. In the region, a set of submarine canyons are developed. The canyons are 2-4 km apart, and are separated by sedimentary ridges. Water depth ranges from 400 to 1500 m. Regional slope is about 2 degree in average. Numerous submarine landslides are developed. On seismic profiles, the landslides are easily differentiated from the normal sedimentary layers by their deformed and/or chaotic reflections. They are bounded by head scars and basal gliding planes. Within the landslides, faults and folds are common. Totally 75 landslides were defined, including 56 slumps and 19 two- or multi-stage landslide complexes. The geomorphological parameters of the submarine landslides, including their area, volume, runout distance, headscarp height, headscarp gradient and landslide slope gradient were measured. Statistics suggested that the slandlides are generally 5-40 km2 in area, and runout distance of the landslides is usually less than 5-6 km. Most landslides are developed on slopes of 4 to 8 degrees in gradient. The landslides are majorly distributed in the head regions or on the walls of the canyons. It is obviously that the generation of the submarine landslides is related with the canyons. It is suggested that increase of local slope gradient resulting from the headward erosion and/or downward incision of the canyons is responsible for the development of the submarine landslides.
Location: GEOMAR East shore
Address: Wischhofstr. 1-3 / D-24148 Kiel