Characteristics of buried paleo-channels in the Western South Yellow Sea during the Late Last Glaciation

Abstract

Original scientific paper Studies on the evolution of paleo-channels in coastal areas are important for submarine engineering construction and to reveal changes in the global paleoenvironment. Thus, to explore the characteristics of paleo-channels during the late Last Glaciation in the western South Yellow Sea, digital terrain analysis method and ArcGis river extraction function were employed, high-resolution shallow stratigraphic seismic profiles and core data were analysed, and river empirical formulas were used to determine river properties and river patterns. Results indicate that the ancient river system during the late Last Glaciation of the South Yellow Sea shelf is divided into paleo-Yellow (Huanghe) and paleo-Yangtze (Changjiang) Rivers. The paleo-channels near 33°N belong to the paleo-Yangtze River, and generally flow from east to northeast. The paleo-channels around 35°N and 123,5°E are part of the paleo-Yellow River. Compared with the paleo-Yellow River, the paleo-Yangtze River is prone to horizontal migration and has higher penetration depths and discharge. Based on the slope-width method, the paleo-Yellow River system can be considered mainly as a meandering river, whereas the paleo-Yangtze River system is largely a braided river. Remarkable differences are found between the paleo-Yangtze River and the paleo-Yellow River. The characteristics of buried paleo-channels during the late Last Glaciation can be useful in predicting the incident potential hazard of submarine engineering and in revealing the paleoenvironment changes in the South Yellow Sea shelf. Keywords: buried paleo-channels; paleo-Yellow River; paleo-Yangtze River; submarine engineering; western South Yellow Sea Značajke podzemnih paleolitskih korita u zapadnom Južnom Žutom moru tijekom kasnog posljednjeg ledenog dobaIzvorni znanstveni članak Istraživanja o evoluciji paleolitskih korita u obalnim područjima važna su za konstrukcije podmorskog inženjerstva i za otkrivanje promjena u globalnom paleolitskom okruženju. Stoga je za istraživanje značajki paleo-korita tijekom kasnog posljednjeg ledenog doba u zapadnom Južnom Žutom moru primijenjena digitalna metoda analize terena i ArcGis funkcija porijekla rijeke, analizirani su plitki stratigrafski seizmički profili visoke rezolucije i osnovni podaci, a rabljene su empirijske formule rijeke za određivanje riječnih svojstava i struktura. Rezultati pokazuju da je drevni riječni sustav tijekom kasnog posljednjeg ledenog doba grebena Južnog Žutog mora podijeljen na paleo-Žutu (Huanghe) i paleo-Yangtze (Changjiang) rijeku. Paleo-korita blizu 33°N pripadaju paleo-Yangtze rijeci i uglavnom teku od istoka do sjeveroistoka. Paleo-korita oko 35°N i 123,5°E dio su paleo-Žute rijeke. U usporedbi s paleo-Žutom rijekom, paleo-Yangtze rijeka inklinira horizontalnom premiještanju, ima veću prodornu moć i veću količinu vode. Na temelju metode širine nagiba sustav paleo-Žute rijeke može se smatrati uglavnom krivudavim dok je sustav paleo-Yangtze rijeke uglavnom sustav račvaste (braided) rijeke. Pronađene su z...

Distinctive Sedimentary Evolution at the East Edge of the Central Yellow Sea Mud Over the Past 45 kyr: Evidence From Detrital Mineralogy

“…Moreover, caliche nodules were also found in the west CYSM with some terricolous plant fragments during the MIS2 (Wang et al, 2014b), which further confirms that the dendritic channels of the paleo-Yellow River were widely distributed on the SYS. These results were also validated by Song et al (2016) who used a more detailed network of seismic profiles that covered the area from 32 °N to 36 °N and 120 °E to 125 °E (Figure 9B). However, as influenced by the relatively cold and dry climate, sediment supplies from the paleo-Yellow River to the eastern continental shelf of China would be relatively low, and even eroded under the functions of transport and blowing by the winter monsoon (An et al, 1991).…”

“…The RSL in the eastern China seas can be generally characterized by a rapid fall from 90 to 140 m bpsl, relative stabilization at 140 m bpsl, and a rapid rise from 140 to 60 m bpsl in the early FIGURE 9 | Schematic diagrams for variation of coastal lines (Li et al, 2014a), distribution of paleo-rivers (Liu et al, 2002;Wellner and Bartek, 2003;Liu et al, 2010a;Song et al, 2016), evolution of hydrodynamic regimes (Uehara and Saito, 2003;Lü et al, 2010;Wang et al, 2014a), and formation of the CYSM (mud thickness is from Wang et al, 2014b) MIS2, Last Glacial Maximum (LGM), and early last deglaciation, respectively (Figure 8A). In particular, the continental shelf of eastern China was completely exposed, and the paleo-coastal line occurred at the continental shelf edge of the East China Sea in LGM (Figure 9B; Lambeck and Chappell, 2001;Li et al, 2014a).…”

“…FIGURE 9 | Schematic diagrams for variation of coastal lines(Li et al, 2014a), distribution of paleo-rivers(Liu et al, 2002;Wellner and Bartek, 2003;Liu et al, 2010a;Song et al, 2016), evolution of hydrodynamic regimes(Uehara and Saito, 2003;Lü et al, 2010;Wang et al, 2014a), and formation of the CYSM (mud thickness is fromWang et al, 2014b) in the South Yellow Sea during MIS3a (A), LGM (B), ~10-6.5 kyr (C), and 6.5 kyr-present (D). The dotted line represents the inferred paths and ranges.…”