## 4 Results
### Lithofacies Analysis
#### 4.3.1 Lithofacies
\begin{table}
\begin{tabular}{l l l l l} \hline \hline
**Facies Code** & **Lithofacies** & **Grain Size** & **Description** & **Interpretation** \\ \hline \multirow{9}{*}{Ss} & \multirow{9}{*}{Structureless sandstone} & \multirow{9}{*}{Coarse to fine-grained fine-grained sand} & Light grey to brownish-red sandstones \& \\  & & & lightofacies Ss consists of massive & \\  & & & sandstones without sedimentary structures (Figures 5 and 6G). & This lithofacies is \\  & & & structures (Figures 5 and 6G). & interpreted as traction \\  & & & Occasional mudstone rip-up & carpets and/or sediment \\  & & & clasts and mud strips occur in & gravity flows [51; 53; 63]. \\  & & & lithofacies Ss. Characterized by & \\  & & & abrupt contact at the base & \\  & & & and top. & \\ \hline \multirow{9}{*}{Sm} & \multirow{9}{*}{Massive siltstone} & \multirow{9}{*}{Silt} & Light grey to brownish-red & \\  & & & well-sorted sandstone. & \\  & & & Mudstone rip-up casts are & This lithofacies likely \\  & & & occasionally observed. This & represents a low-energy \\  & & & lithofacies is characterized by a & sedimentary environment \\  & & & uniform distribution of sandy & due to the rapid \\  & & & grains, poorly developed & accumulation of \\  & & & bedding, and frequent & suspended fine-grained \\  & & & interbedding with lithofacies & sediments [24; 64]. \\  & & & Mm and Mhb & \\  & & & (Figures 5 and 6H). & \\ \hline \multirow{9}{*}{Shb} & \multirow{9}{*}{Horizontal bedded siltstone} & \multirow{9}{*}{Silt} & Lithofacies Shb consists of light grey to brownish-red siltstone, interbedded with dark grey & This lithofacies is \\  & & & argillaceous siltstone & interpreted as a \\  & & & (Figures 5 and 6I). Parallel & low-energy sedimentary \\  & & & laminations are commonly & environment such as the \\  & & & observed. This lithofacies & waning stages of flood \\  & & & usually overlies lithofacies Ss, & deposition [65; 66]. \\  & & & Stc, Spc, or Spb, and transitions & \\  & & & into facies Mm. & \\ \hline \multirow{9}{*}{Src} & \multirow{9}{*}{Rippled siltstone} & \multirow{9}{*}{Silt} & This lithofacies is \\  & & & lithofacies Src consists of light grey to brownish-red sediment, reflecting moderate mud content. & environment \\  & & & symmetrical, wave, and & characterized by weak \\  & & & reflecting moderate mud content. & hydrodynamic conditions \\  & & & & and low sediment supply \\  & & & climbing ripples are common & [53; 67]. Variations in \\  & & & (Figures 5 and 6J). Lithofacies Src & ripple cross-lamination \\  & & & is usually found above & reflect alternating \\  & & & lithofacies Spb, Spc, or Stc. & deposition from traction \\  & & & & and suspension \\  & & & & sedimentation [53]. \\ \hline \multirow{9}{*}{Cd} & \multirow{9}{*}{Chaotic deposits sand, silt and mud} & Lithofacies Cd consists of & \\  & & & conglomerate, sandstone, and & \\  & & mudstone clasts, exhibiting poor & \\  & & & sorting, an absence of bedding, & \\  & & and highly variable clast sizes. & \\  & & & Soft-sediment deformed & \\  & & & structures such as collapse fold & \\  & & & bedding, flame structures, & [13; 68; 69; 70]. \\  & & & convolute bedding, and & \\  & & & deformed bedding are common & \\  & & & (Figures 5 and 6K). & \\ \hline \end{tabular}
\end{table} 
Table 1: _Cont._Figure 5: Lithofacies division of the delta front depositional system in the Oigu Formation. Figure 6: _Cont._