Submarine landforms associated with turbidity currents are well developed in the South China Sea (SCS). There are numerous submarine canyons in the continental slopes. Sediment waves and cyclic step bedforms related to the supercritical turbidity currents are distributed along the thalwegs, on the overbank areas or off the outlets of some submarine canyons. However, large-scale submarine fans at the foot of the continental slopes are rarely observed; on the other hand, a high proportion of turbidites are found being preserved in the pelagic to the hemipelagic succession of the abyssal plain. We suggest that the turbidity currents traversing the submarine canyons could be of high energy, enough to sustain a longer distance transport along the abyssal plain even after the deceleration at the foot of the continental slopes. The turbidity-current associated landforms in the SCS were mostly initiated in the late Miocene, and might be closely related to the active plate tectonics in the SCS and surrounding areas.
ZHONG Guangfa
,
ZHU Benduo
,
WANG Liaoliang
. Turbidity current related landforms in the South China Sea[J]. Science & Technology Review, 2020
, 38(18)
: 75
-82
.
DOI: 10.3981/j.issn.1000-7857.2020.18.012
[1] 广州海洋地质调查局. 南海地质地球物理图系(1:2000000)[M]. 天津:中国航海图书出版社, 2015.
[2] Zhong G F, Cartigny M J B, Kuang Z G, et al. Cyclic steps along the South Taiwan Shoal and West Penghu submarine canyons on the northeastern continental slope of the South China Sea[J]. Geological Society of America Bulletin, 2015, 127(5/6):804-824.
[3] Kuang Z G, Zhong G F, Wang L L, et al. Channel-related sediment waves on the eastern slope offshore Dongsha Islands, northern South China Sea[J]. Journal of Asian Earth Sciences, 2014, 79:540-551.
[4] Yin S R, Zhong G F, Guo Y Q, et al. Seismic stratigraphy and tectono-sedimentary framework of Pliocene to recent Taixinan foreland basin in the northeastern continental margin, South China Sea[J]. Interpretation, 2016, 4(3):SP21-SP32.
[5] Yin S R, Wang L L, Guo Y Q, et al. Morphology, sedimentary characteristics, and origin of the Dongsha submarine canyon in the northeastern continental slope of the South China Sea[J]. Science China:Earth Sciences, 2015, 58(6):971-985.
[6] Zhong G F, Liang J Q, Guo Y Q, et al. Integrated corelog facies analysis and depositional model of the gas hydrate-bearing sediments in the northeastern continental slope, South China Sea[J]. Marine and Petroleum Geology, 2017, 86:1159-1172.
[7] He Y, Zhong G F, Wang L L, et al. Characteristics and occurrence of submarine canyon-associated landslides in the middle of the northern continental slope, South China Sea[J]. Marine and Petroleum Geology, 2014, 57:546-570.
[8] Huang K, Zhong G, Wang L, et al. Seismic facies in the Pearl River Submarine Canyon, northern South China Sea[J]. SEG Technical Program Expanded Abstracts, 2018:1738-1742.
[9] Wang R W, Zhong G F, Wang L L, et al. Types and characteristics of seismic facies in the northern South China Sea basin[J]. SEG Technical Program Expanded Abstracts, 2018:1590-1594.
[10] Damuth J E. Migrating sediment waves created by turbidity currents in the northern South China Basin[J]. Geology, 1979, 7:520-523.
[11] Fildani A, Normark W R, Kostic S, et al. Channel formation by flow stripping:Large-scale scour features along the Monterey East Channel and their relation to sediment waves[J]. Sedimentology, 2006, 53(6):1265-1287.
[12] 关永贤, 杨胜雄, 宋海斌, 等. 南海西南部深水水道的多波束地形与多道反射地震研究[J].地球物理学报, 2016, 59(11):4153-4161.
