Characteristics and Controlling Factors of Coarse-Grained Turbidite Sediment Waves in Submarine Channel-Lobe System of the Ruvuma Basin, East Africa

Key words: 
• Ruvuma Basin /
• channel-lobe system /
• coarse-grained turbidite sediment waves /
• characteristics /
• controlling factors /

Abstract: Research of coarse-grained turbidite sediment waves in submarine channel-lobe system can deepen the geological understanding of deep-water transporting process. The special sedimentary bodies, which are easy to be reworked later found in a submarine channel-lobe system of the Ruvuma Basin, East Africa, are identified and explained through the use of advanced geophysical imaging technologies and the analysis of the seismic relief. The causes and influencing factors are discussed by describing the shape, scale, migration style, thickness variations, and distribution of the coarse sediment waves. The coarse-grained turbidite sediment waves which are found in submarine channel-lobe system in Ruvuma Basin have various morphology and antidune bedforms. The small scale sediment waves with limited extension are mainly developed in the channel. While, large inclusive sediment waves distributes in channel-lobe transition zone, wave heights are in the region of 45~110 m, and wavelengths are up to over one thousand meters. The overall scale is larger than the coarse-grained sediment waves that have been identified in worldwide other regions. The coarse-grained turbidite sediments waves in the Ruvuma Basin were mainly controlled by tectonic deformation, hydraulic jumps of the supercritical flow, topography and bottom current activities.