GRAIN SIZE DISTRIBUTION OF SURFACE SEDIMENTS IN THE SOUTHWESTERN SOUTH CHINA SEA AND TRANSPORT TREND ANALYSIS

This paper analyzes the grain-size distribution of surface sediments of the Chanthaburi coast of Thailand to investigate the sedimentary environment and its evolution to better use and protect the coast. The Flemming triangle method, the grade-standard deviation method, and the Gao–Collins grain-size trend analysis method (GSTA model) were used to study the dynamic sedimentary environment of the area and provide preliminary identification of source materials. There are seven types of surface sediments on this coast, with grain sizes (φ) generally consisting of sand and silt. Sorting is generally poor, and becomes gradually poorer with distance offshore. Skewness is generally positive. The study area is mainly composed of sand and silt, indicating that the hydrodynamics are strong. The results of grade-standard deviation analysis indicate that sediment grain size b (3.25–4.5φ) is a sensitive indicator of environmental change. This sediment type exhibits a relatively complex transport trend, mainly characterized by northwestward and northeastward transport from sea to land. Sediments at the mouth of the Chanthaburi Estuary and the Welu River fluctuate under the influence of tidal currents. Based on the results of grade-standard deviation analysis and grain-size trend analysis, the study area was divided into three provinces, representing different sedimentary environments and material sources. Compared with tidal-controlled estuaries in the temperate regions of eastern China, the two tropical estuaries examined in this study exhibited smaller suspended sediment loads, runoff amounts, and tidal ranges. However, hydrodynamic conditions were generally stronger. The main reasons for the similarities and differences in the transport trends of sediments in these estuaries were differences in hydrodynamic conditions and the specifics of regional topography.

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Dynamic control on grain-size distribution of terrigenous sediments in the western South China Sea: Implication for East Asian monsoon evolution

Science Bulletin ◽

10.1007/s11434-008-0078-y ◽

2008 ◽

Vol 53 (10) ◽

pp. 1533-1543 ◽

Cited By ~ 2

Author(s):

GuoCheng Chen ◽

HongBo Zheng ◽

JianRu Li ◽

Xin Xie ◽

Xi Mei

Keyword(s):

Grain Size ◽

South China Sea ◽

Size Distribution ◽

Grain Size Distribution ◽

South China ◽

Asian Monsoon ◽

East Asian Monsoon ◽

East Asian ◽

Dynamic Control ◽

Western South China Sea

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Chemical speciation of 12 metals in surface sediments from the northern South China Sea under natural grain size

Marine Pollution Bulletin ◽

10.1016/j.marpolbul.2008.01.004 ◽

2008 ◽

Vol 56 (4) ◽

pp. 786-792 ◽

Cited By ~ 13

Author(s):

Xuelu Gao ◽

Shaoyong Chen ◽

Aimin Long

Keyword(s):

Grain Size ◽

South China Sea ◽

South China ◽

Chemical Speciation ◽

Surface Sediments ◽

Northern South China Sea ◽

China Sea

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DISTRIBUTION OF THE CLAY MINERALS IN SURFACE SEDIMENTS OF THE SOUTH CHINA SEA AND THEIR PROVENANCE

Marine Geology & Quaternary Geology ◽

10.3724/sp.j.1140.2010.04057 ◽

2010 ◽

Vol 30 (4) ◽

pp. 57-66 ◽

Cited By ~ 1

Author(s):

Qian GE ◽

Fengyou CHU ◽

Jingpu LIU ◽

Yuansheng DU ◽

Zuo XUE ◽

...

Keyword(s):

South China Sea ◽

Clay Minerals ◽

South China ◽

Surface Sediments ◽

The South China Sea ◽

The South ◽

China Sea

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Clay Mineralogy and Geochemistry of the Pockmarked Surface Sediments from the Southwestern Xisha Uplift, South China Sea: Implications for Weathering and Provenance

Geosciences ◽

10.3390/geosciences11010008 ◽

2020 ◽

Vol 11 (1) ◽

pp. 8

Author(s):

Mei Zhang ◽

Hongfeng Lu ◽

Qing Chen ◽

Gayan Bandara ◽

Hui Zhang ◽

...

Keyword(s):

South China Sea ◽

Clay Minerals ◽

South China ◽

Surface Sediments ◽

Northern South China Sea ◽

Clay Mineralogy ◽

Xrd Analysis ◽

Average Weight ◽

X Ray ◽

China Sea

In the northern South China Sea, pockmarks are widely distributed on the seabed offshore on the southwestern Xisha Uplift. The mineralogy and geochemistry of the clay minerals and surface sediments from the pockmark field were identified using X-ray diffraction (XRD) analysis and X-ray fluorescence (XRF) analysis to trace the provenance, weathering, and sediment transportation system in the area. The clay minerals are primarily comprised of illite, smectite, kaolinite, and chlorite, showing a distribution of average weight percentages of 35%, 35%, 18%, and 13%, respectively. Based on the surrounding fluvial drainage basins and various transport mechanisms (current or monsoon), illite and chlorite primarily originate from rivers in Taiwan and the Mekong and Red Rivers. Kaolinite primarily originates from the Pearl River, and smectite derived from the Luzon arc system is primarily transported by surface currents with significant influence from the Kuroshio intrusion.

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