## 3 Data and Method
### Methods
#### 3.3.3 Morphometric Analysis of Submarine Channels  
Morphometric dimension analysis (width, height, length, gradient, sinuosity, aspect ratio, and cross-sectional area) of genetically related channel complexes is an effective quantitative interpretation tool. It can reveal scaling relationships and infer the relation between sediment conduit morphology, sedimentary processes, and paleoenvironment interpretation [18; 19; 25].  
The quantitative analyses of the channel system followed the methods of [PERSON], [PERSON], [PERSON] and [PERSON] [17], and [PERSON], [PERSON], [PERSON], [PERSON] and [PERSON] [19] that are represented in Figure 7. These involved a combination of manual and auto-tracking procedures. Then, the incision interpretations were converted into the incision (channels) surfaces. The cross-sections are drawn perpendicular to these incision surfaces to calculate the morphometric parameters measured at an interval average of 150 m (Figure 7). Furthermore, the western-middle-eastern definition is based on the three zonation on the Waka 3D seismic reflection survey that consider the source of sediment in the west and the transport direction to the east (Figure 1a).  
Figure 6: Seismic facies of filling deposits from four different channels complexes in this study. See Section 4.1 for detailed description. Note that the thick black line is the interpreted channel incision, the red line is the younger channel surface, the thin black line is the fault, and the yellow dashed line is isolated low to high seismic amplitude.  
The morphometric measurements of the channel complexes investigated in the study area are as follow (Figure 7):  
* Height is a vertical distance from thalweg to the overspill point.
* Top width is defined as the distance between overspill points on each channel complexes margin.
* Base width is the distance between two lower points in the channels floor of the channel complexes.
* Aspect ratio is defined as a ratio between top width and height of the channels complexes cross-sectional area (CSA).
* Sinuosity (i.e., the length between a reference point and along channels complexes axis) and channel gradient are calculated based on thalweg depth changes along the channel complexes' distance.  
In addition, the overspill point is located between the channel flank and wall. Detailed simuosity classification by [PERSON], [PERSON], [PERSON] [27] was used in this study. The low sinuosity is defined between 1.05 and 1.20, whereas, for straight channels, complexes systems are between 1.00 to 1.05, and for high sinuosity systems, greater than 1.20. Moreover, all the morphometric elements on morphometry analysis are presented in the cross-plot. Among them is the scaling relationship, where R is the correlation coefficient that measures the strength and the direction of a linear relationship among two variables on the cross-plot. R\({}^{2}\) is a coefficient of determination that quantify the proportion of the variance (fluctuation) of one variable that is predictable from the other variable on the cross-plot [52].  
Figure 7: Morphometry elements of the channel’s complexes that were analyzed in this study.