|
|
|
|
|
Zhao, Minghui; He, Enyuan; Sibuet, Jean-claude; Sun, Longtao; Qiu, Xuelin; Tan, Pingchuan; Wang, Jian. |
P-wave velocity models were obtained by forward and inverse modeling from 38 ocean bottom seismometers deployed in the central East sub-basin of the South China Sea (SCS). Four types of crust have been defined; a) thin oceanic crust (<5 km), b) typical oceanic crust (5-6 km), c) thick oceanic crust hosting post-spreading volcanoes (>6 km) with significant intrusive roots, and d) thick oceanic crust with enhanced spreading features (>6 km) but without significant roots. Within the central East sub-basin, the thin oceanic crust, only identified inside a 80-km wide zone, is located within an overall 150-km wide domain characterized by N055° seafloor spreading trends. The post-spreading volcanoes were formed during a N-S tensional episode around 6-10... |
Tipo: Text |
|
Ano: 2018 |
URL: http://archimer.ifremer.fr/doc/00427/53882/54951.pdf |
| |
|
| |
|
|
Huang, Haibo; Qiu, Xuelin; Pichot, Thibaud; Klingelhoefer, Frauke; Zhao, Minghui; Wang, Ping; Hao, Tianyao. |
Evolution of the continental margins of the South China Sea (SCS) is one of the open questions when discussing continental breakup and seafloor spreading. We processed data from a wide-angle seismic profile (OBS2011–1), which passes through the northwestern margin of the SCS, and performed travel time modeling to obtain the seismic velocity structures. The modeling results show a stepwise variation of the crustal thicknesses from continental margin to oceanic basin. Stretching factor of the upper crust is nearly double the estimate of the lower crust along the Zhongsha Trough. The lower crust shows asymmetrical upwelling towards the trough center, accompanied by ∼0.3 km/s of the velocity increase due to magmatic addition. The upper and lower crusts have... |
Tipo: Text |
Palavras-chave: Seismic tomography; Continental tectonics: extensional; Crustal structure; Rheology: crust and lithosphere. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00500/61189/64720.pdf |
| |
|
|
Liu, Siqing; Zhao, Minghui; Sibuet, Jean-claude; Qiu, Xuelin; Wu, Jonny; Zhang, Jiazheng; Chen, Chuanxu; Xu, Ya; Sun, Longtao. |
An E-W oriented OBS2015-2 wide-angle refraction profile was shot in the northeastern South China Sea (SCS) between refraction profiles T1 and T2 in order to better understand the variability of the crustal composition and the role of specific tectonic features. P-wave velocity models established from forward and inversion modeling imaged a 12 to 15 km-thick thinned continental crust and a high velocity layer (HVL) in the lower crust which is interpreted as magmatic underplating. Profile OBS2015-2 cut across the Taiwan transfer zone (TTZ), which separates two consecutive rifted segments of different orientations in the northeastern SCS. The TTZ is a well-defined upper crustal feature characterized by a HVL with different thickness on both sides. We have... |
Tipo: Text |
Palavras-chave: Northeastern South China Sea; Continent-ocean boundary (COB); Wide-angle reflection/refraction data; Thinned continental crust intruded by post-rifting volcanism; Taiwan transfer zone (TTZ). |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00443/55458/56974.pdf |
| |
|
| |
|
|
|