scholarly journals A tuffaceous volcaniclastic turbidite bed of Early Miocene age in the Temburong Formation of Labuan, North West Borneo and its implications for the Proto‐South China Sea subduction in the Burdigalian

2020 ◽  
Author(s):  
Stuart D. Burley ◽  
H. Tim Breitfeld ◽  
David ‘Stan’ Stanbrook ◽  
Robert J. Morley ◽  
Jochen Kassan ◽  
...  
Keyword(s):  
South China Sea ◽  
South China ◽  
Early Miocene ◽  
North West ◽  
China Sea

Where are the proto-South China Sea slabs? SE Asia plate tectonic and mantle flow insights from TERRA global mantle convection models

2020 ◽  
Author(s):  
Yi-An Lin ◽  
Lorenzo Colli ◽  
Jonny Wu
Keyword(s):  
South China Sea ◽  
South China ◽  
Late Eocene ◽  
Early Miocene ◽  
Philippine Sea Plate ◽  
Plate Tectonic ◽  
China Sea ◽  
Se Asia ◽  
Plate Models ◽  
Geodynamic Models

<p>In this study we explored the contrasted plate tectonic reconstructions proposed for the proto-South China Sea and SE Asia. We implemented four different end-member plate models into global geodynamic models to test their predicted mantle structure against tomography. All models reproduced the Sunda slabs beneath Peninsular Malaysia, Sumatra and Java and the proto-South China Sea (PSCS) slabs beneath present Palawan, northern Borneo, and offshore Palawan; some models also predicted slabs under the southern South China Sea. PSCS slabs generated from double-sided PSCS subduction and earlier Borneo rotation generated a slightly better fit to tomography but pure southward PSCS subduction was also viable. A smaller Philippine Sea plate (PSP) with a short ~1000 km restored northern slab (i.e. Ryukyu slab) was clearly superior to a very long >3000 km slab. Mantle flows generated from our geodynamic models suggest strong upwellings under Indochina during the late Eocene to Oligocene. Our models generated strong downwellings under the South China Sea in the late Cenozoic that did not support a deep-origin ‘Hainan plume’. </p><p>The following plate models variants were assimilated in the geodynamic models: (1) southward vs. double-sided PSCS subduction; (2) early Borneo counterclockwise rotations during the Oligocene to Early Miocene vs. later rotations (mid- to Late Eocene and Early Miocene); (3) a smaller Philippine Sea plate restored with a shorter ~1000 km northern slab vs. a longer >3000 km slab. This study assimilates four different plate models into the numerical model TERRA (Bunge et al., 1998). We digitally re-built in GPlates (Boyden et al., 2011) the implemented the plate models as a set of continuously closing plates in order to generate a global self-consistent velocity field to be assimilated into the convection models. The temperature fields were converted to seismic velocities assuming a Pyrolite composition and equilibrium mineralogy. We quantify the correlation between our geodynamic models and seismic tomography within SE Asia. For the tomography models S40RTS and LLNL-G3Dv-JPS we explicitly accounted for their finite resolution (Ritsema et al., 2011; Simmons et al. 2019).</p>

scholarly journals Tracking the Detrital Zircon Provenance of Early Miocene Sediments in the Continental Shelf of the Northwestern South China Sea

Minerals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 752
Author(s):  
Ce Wang ◽  
Letian Zeng ◽  
Yaping Lei ◽  
Ming Su ◽  
Xinquan Liang
Keyword(s):  
South China Sea ◽  
Continental Shelf ◽  
South China ◽  
Detrital Zircon ◽  
Early Miocene ◽  
Sediment Provenance ◽  
Additional Contribution ◽  
Lower Miocene ◽  
Paleogeographic Reconstruction ◽  
China Sea

Sediment provenance studies have become a major theme for source-to-sink systems and provide an important tool for assessing paleogeographic reconstruction, characterizing the depositional system, and predicting reservoir quality. The lower Miocene is an important stratigraphic unit for deciphering sediment evolution in the continental shelf of the northwestern South China Sea, but the provenance characteristics of this strata remain unclear. In this study, detrital zircon U-Pb geochronology and Lu-Hf isotopes from the lower Miocene Sanya Formation in the Yinggehai-Song Hong Basin were examined to study the provenance and its variation in the early Miocene. U-Pb dating of detrital zircons yielded ages ranging from Archean to Cenozoic (3313 to 39 Ma) and displayed age distributions with multiple peaks and a wide range of εHf(t) values (from −27.2 to +8.5). Multi-proxy sediment provenance analysis indicates that the Red River system was the major source for the sediments in the northern basin, with additional contribution from central Vietnam, and the Hainan played the most important role in contributing detritus to the eastern margin of the basin in the middle Miocene. This paper highlights the provenance of early Miocene sediments and contributes to paleogeographic reconstruction and reservoir evaluation.

Bathyconchoecia liui n. sp., a new species of ostracod (Myodocopa, Halocyprididae) from the South China Sea

Crustaceana ◽  
2014 ◽  
Vol 87 (8-9) ◽  
pp. 1027-1035 ◽  
Author(s):  
Jian-Qiang Yin ◽  
Qing-Chao Chen ◽  
Kai-Zhi Li
Keyword(s):  
New Species ◽  
South China Sea ◽  
South China ◽  
Present Species ◽  
Similar Species ◽  
North West ◽  
China Sea ◽  
Fifth Limb ◽  
Bathypelagic Zone ◽  
A New Species

A new species of halocyprid ostracod,Bathyconchoecia liui, from the bathypelagic zone of the Nansha Trough (North-West Borneo Trough, southern South China Sea) is described and illustrated. It is compared with the closely similar speciesB. angeliGeorge, 1977. The present species is easily distinguished fromB. angeliby the structures of the toothed edges of the mandibular basis and coxa, and by the segmentation of the fifth limb.

Seasonal and spatial distribution of chaetognaths on the north-west continental shelf of the South China Sea

2014 ◽  
Vol 94 (4) ◽  
pp. 837-846 ◽  
Author(s):  
X. Wu ◽  
K. Li ◽  
L. Huang ◽  
J. Yin ◽  
Y. Tan
Keyword(s):  
Spatial Distribution ◽  
South China Sea ◽  
Continental Shelf ◽  
South China ◽  
The South China Sea ◽  
The South ◽  
North West ◽  
China Sea ◽  
The North ◽  
Region I

The seasonal variation and spatial distribution of chaetognaths were studied based on samples collected from July to August 2006 (summer), December 2006 to January 2007 (winter), and in April 2007 (spring) on the north-west continental shelf of the South China Sea. A total of 19 species of chaetognaths were identified. The average chaetognath abundances (mean ±SD) were 54.0 ± 44.5, 36.8 ±16.7 and 48.9 ± 95.5 ind. m−3 in summer, winter and spring, respectively. Flaccisagitta enflata and Serratosagitta pacifica were the dominant species during the whole sampling period, and F. enflata determined the spatial distribution of total chaetognath abundance. According to the topography and hydrological conditions, the survey area was divided into three sub-regions: inshore waters of the western Guangdong (Region I), inshore waters to the east of Hainan Island (Region II) and offshore waters from the western Guangdong to Hainan Island (Region III). The community structure and abundance distribution of chaetognaths varied significantly between the three sub-regions. The species richness was significantly different among the three sub-regions, with the lowest in Region I and the highest in Region III. The species richness was correlated positively with temperature and salinity. The abundance of chaetognaths was significantly higher in Region I than in both Regions II and III in summer and spring. The increasing food availability caused by the cold eddy, coastal upwelling and the western Guangdong coastal current was able support a greater abundance of chaetognaths during warm seasons on the north-west continental shelf of the South China Sea.

Sign in / Sign up

Export Citation Format

Share Document