## 5 Discussion  
### Development of Submarine Channels  
During the Quaternary period, channels (including anyons and channels complexes) acted as conduits for transferring sediment from the source area in the west (onshore Southern Alps) to the depositional area in the east (Figures 1 and 2). Furthermore, seismic facies, attributes, and morphological analysis in our zone of interest revealed some complexes of incisions with V and U shaped that are erosionally and construcationally confined (Figures 4 and 5). In addition, isolated bright amplitude with relatively linear and nonlinear correlations on the morphometric scaling relationships, also indicate submarine channels [4, 6, 19, 53, 54, 55, 56]. This observation is also supported by [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON] and [PERSON] [28], and [PERSON], [PERSON], [PERSON] and [PERSON] [30], who concluded that submarine channels in Waka 3D seismic reflection survey are present from the Oligocene to Quaternary. The first stage of the submarine channel's development is characterized by a V to U-shaped incision that cross-cuts the older deposits (truncated reflection termination pattern in Figures 5 and 6). The existence of isolated low to high seismic amplitude at the base of the channels (Figures 6 and 9) and the smaller base width distance (compared to the top width) of the channels (Figure 8b) are attributed to the coarse-grained basal confinement surface at the base of the turbidity flow. This contributed to the widening of the channel complexes [4, 57, 58, 59] when a fall in the equilibrium profile reduced the slope accommodation [60]. In addition, the small values of the base width distance on the western area of the channels (<500 m, see Table 1 and Figure 8b), the V-shaped channel erosionally confined at the lower part of the channels (Figures 5 and 6), together with high correlation and determination coefficients (Table 1), shows a good example of intermittent turbidity flows. On the contrary, the high values of the base width distance of the channels (>500m, see Table 1 and Figure 8b) with the U-shaped construcationally confined channels indicate local factors of the channel's development (e.g., channel wall's collapse) or the existence of another turbidity flow widening the base of the channel complexes. These may be the product of sediment supply, transport regime, and gradient variations as the system was developing [5, 6, 10, 12, 14]. Figure 9: 3D view of dip angle (right images) and depth RMS Amplitude slice (left images) of (**a**) Type 1, (**b**) Type 2, (**c**) Type 3, and (**d**) Type 4 of channels complexes in this study. Dashed black and red lines represent channel outline and sediment waves, respectively. See Figure 4 for the channel’s location. The next stage is indicated lateral shifting of channel complexes (Types 2 and 4), and the vertically degrading channel that associated with Types 1 and 3 (Figure 6). A relatively high value also indicates this lateral shifting on the top width of the channel (>1800 m, see Table 1, Figures 8a and 9) and cross-sectional area (>0.02 km\({}^{2}\), see Table 1 and Figure 8d). Some of the higher values of the top width and cross-sectional area from other types of channel complexes are attributed to local submarine channel wall failures. This lateral shifting is usually the product of channel avulsion or bend cut-off [5; 12]. Furthermore, the vertically degrading channels complexes in the study area are represented by the channel's height, where Type 1 has the highest average height of 298.5 m (Table 1 and Figure 8c). Once the channel equilibrium profile continues to rise, the submarine channel starts to be aggraded, with no significant lateral offset of depositional facies [6; 60]. Overall, the morphometry of submarine channels has been influenced by local factors in this continental slope environments (e.g., submarine wall's collapse, different maturity of turbidite flows, and slope accommodation).