Postseafloor Spreading Volcanism in the Central East South China Sea and Its Formation Through an Extremely Thin Oceanic Crust
P wave velocity models were obtained by forward and inverse modeling from 38 ocean bottom seismometers deployed in the central East subbasin 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 c...
Published in: | Geochemistry, Geophysics, Geosystems |
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Online Access: | http://ir.gig.ac.cn/handle/344008/38572 https://doi.org/10.1002/2017GC007034 |
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ftchacadscgigcas:oai:ir.gig.ac.cn:344008/38572 2023-05-15T16:02:33+02:00 Postseafloor Spreading Volcanism in the Central East South China Sea and Its Formation Through an Extremely Thin Oceanic Crust Zhao, Minghui He, Enyuan Sibuet, Jean-Claude Sun, Longtao Qiu, Xuelin Tan, Pingchuan Wang, Jian 2018-03-01 http://ir.gig.ac.cn/handle/344008/38572 https://doi.org/10.1002/2017GC007034 英语 eng AMER GEOPHYSICAL UNION GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS http://ir.gig.ac.cn/handle/344008/38572 doi:10.1002/2017GC007034 Geochemistry & Geophysics PLUME-RIDGE INTERACTION MID-ATLANTIC RIDGE PACIFIC RISE TRACE-ELEMENT INDIAN RIDGE CONTINENTAL BREAKUP TECTONIC EVOLUTION PHOENIX RIDGE DRAKE PASSAGE HAINAN PLUME 期刊论文 2018 ftchacadscgigcas https://doi.org/10.1002/2017GC007034 2020-12-22T07:21:27Z P wave velocity models were obtained by forward and inverse modeling from 38 ocean bottom seismometers deployed in the central East subbasin 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 postspreading 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 subbasin, the thin oceanic crust, only identified inside an 80 km wide zone, is located within an overall 150 km wide domain characterized by N055 degrees seafloor spreading trends. The postspreading volcanoes were formed during a N-S tensional episode around 6-10 Ma, several millions of years after seafloor spreading ceased in the SCS. Seafloor spreading (N055 degrees and N145 degrees) and postspreading (N000 degrees and N090 degrees) features are observed in the morphology of some of these volcanoes. The rupture of the brittle thin oceanic crust was focused where the crust was the weakest, i.e., at the intersection of the extinct spreading ridge with former fracture zones. From geological and geophysical arguments, we suggest that the postspreading volcanism might have been influenced by the Hainan plume activity through a buoyancy-driven partial melting mechanism. Report Drake Passage Guangzhou Institute of Geochemistry: GIG OpenIR (Chinese Academy of Sciences) Drake Passage Indian Mid-Atlantic Ridge Pacific Geochemistry, Geophysics, Geosystems 19 3 621 641 |
institution |
Open Polar |
collection |
Guangzhou Institute of Geochemistry: GIG OpenIR (Chinese Academy of Sciences) |
op_collection_id |
ftchacadscgigcas |
language |
English |
topic |
Geochemistry & Geophysics PLUME-RIDGE INTERACTION MID-ATLANTIC RIDGE PACIFIC RISE TRACE-ELEMENT INDIAN RIDGE CONTINENTAL BREAKUP TECTONIC EVOLUTION PHOENIX RIDGE DRAKE PASSAGE HAINAN PLUME |
spellingShingle |
Geochemistry & Geophysics PLUME-RIDGE INTERACTION MID-ATLANTIC RIDGE PACIFIC RISE TRACE-ELEMENT INDIAN RIDGE CONTINENTAL BREAKUP TECTONIC EVOLUTION PHOENIX RIDGE DRAKE PASSAGE HAINAN PLUME Zhao, Minghui He, Enyuan Sibuet, Jean-Claude Sun, Longtao Qiu, Xuelin Tan, Pingchuan Wang, Jian Postseafloor Spreading Volcanism in the Central East South China Sea and Its Formation Through an Extremely Thin Oceanic Crust |
topic_facet |
Geochemistry & Geophysics PLUME-RIDGE INTERACTION MID-ATLANTIC RIDGE PACIFIC RISE TRACE-ELEMENT INDIAN RIDGE CONTINENTAL BREAKUP TECTONIC EVOLUTION PHOENIX RIDGE DRAKE PASSAGE HAINAN PLUME |
description |
P wave velocity models were obtained by forward and inverse modeling from 38 ocean bottom seismometers deployed in the central East subbasin 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 postspreading 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 subbasin, the thin oceanic crust, only identified inside an 80 km wide zone, is located within an overall 150 km wide domain characterized by N055 degrees seafloor spreading trends. The postspreading volcanoes were formed during a N-S tensional episode around 6-10 Ma, several millions of years after seafloor spreading ceased in the SCS. Seafloor spreading (N055 degrees and N145 degrees) and postspreading (N000 degrees and N090 degrees) features are observed in the morphology of some of these volcanoes. The rupture of the brittle thin oceanic crust was focused where the crust was the weakest, i.e., at the intersection of the extinct spreading ridge with former fracture zones. From geological and geophysical arguments, we suggest that the postspreading volcanism might have been influenced by the Hainan plume activity through a buoyancy-driven partial melting mechanism. |
format |
Report |
author |
Zhao, Minghui He, Enyuan Sibuet, Jean-Claude Sun, Longtao Qiu, Xuelin Tan, Pingchuan Wang, Jian |
author_facet |
Zhao, Minghui He, Enyuan Sibuet, Jean-Claude Sun, Longtao Qiu, Xuelin Tan, Pingchuan Wang, Jian |
author_sort |
Zhao, Minghui |
title |
Postseafloor Spreading Volcanism in the Central East South China Sea and Its Formation Through an Extremely Thin Oceanic Crust |
title_short |
Postseafloor Spreading Volcanism in the Central East South China Sea and Its Formation Through an Extremely Thin Oceanic Crust |
title_full |
Postseafloor Spreading Volcanism in the Central East South China Sea and Its Formation Through an Extremely Thin Oceanic Crust |
title_fullStr |
Postseafloor Spreading Volcanism in the Central East South China Sea and Its Formation Through an Extremely Thin Oceanic Crust |
title_full_unstemmed |
Postseafloor Spreading Volcanism in the Central East South China Sea and Its Formation Through an Extremely Thin Oceanic Crust |
title_sort |
postseafloor spreading volcanism in the central east south china sea and its formation through an extremely thin oceanic crust |
publisher |
AMER GEOPHYSICAL UNION |
publishDate |
2018 |
url |
http://ir.gig.ac.cn/handle/344008/38572 https://doi.org/10.1002/2017GC007034 |
geographic |
Drake Passage Indian Mid-Atlantic Ridge Pacific |
geographic_facet |
Drake Passage Indian Mid-Atlantic Ridge Pacific |
genre |
Drake Passage |
genre_facet |
Drake Passage |
op_relation |
GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS http://ir.gig.ac.cn/handle/344008/38572 doi:10.1002/2017GC007034 |
op_doi |
https://doi.org/10.1002/2017GC007034 |
container_title |
Geochemistry, Geophysics, Geosystems |
container_volume |
19 |
container_issue |
3 |
container_start_page |
621 |
op_container_end_page |
641 |
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1766398217747955712 |