Lithospheric velocity structure of South China Sea basin from ocean bottom seismometer ambient noise tomography

Cheng，Liqun1,2; Fang，Yinxia1,2; Niu，Xiongwei2,9; Li，Tingzi3; Dong，Chongzhi2; Zhao，Yanghui2; Hu，Hao4; Kong，Fansheng2; Tan，Pingchuan2; Ruan，Aiguo2; Lu，Shaoping5,6; Fan，Jianke7; Muhammad，Hafeez Jeofry8; Ding，Weiwei2; Li，Jiabiao2; Du，Xinguang10

2023-10-05

10.1016/j.tecto.2023.230008

Tectonophysics   Impact Factor & Quartile

0040-1951

1879-3266

The South China Sea (SCS) is a typical marginal sea basin formed by the seafloor spreading under the tectonic background of plate convergence. Many crustal-scale studies indicate that the SCS basin has undergone asymmetric spreading, multi-phase ridge jumps, and intense post-spreading volcanic activity. Due to the lack of seismic data in the oceanic basin of the SCS, it remains unclear about the scale and basin control of the Zhongnan fault, the magma source depth of the SCS basin, and the transport channel after the cessation of seafloor spreading. Phase velocity derived from ambient noise surface wave tomography may provide useful information to shed light on the mechanisms of the aforementioned problems. From October 2019 to July 2020, a passive source seismic experiment was carried out with many Ocean Bottom Seismometers (OBS) deployed in a broad area of the SCS. Based on the seismic ambient noise data recorded by 16 OBSs in the SCS basin, we inverted the phase velocity images over a period range of 10–20 s using ambient noise surface wave tomography. Our results indicate that the Zhongnan fault zone is a lithospheric-scale fault, which played a regulating role in the expansion of the SCS basin from the East Subbasin to the Southwest Subbasin. In addition, the low-velocity body in the north flank of the Southwest Subbasin extends from the post-spreading seamounts on the ocean crust to the uppermost mantle (i.e., about 10–30 km), which indicates an oblique magma migration during the post-spreading volcanism.

Ambient noise Ocean Bottom Seismometer (OBS) Phase velocity Post-spreading magmatism South China Sea basin

SCI

English

Others

National Natural Science Foundation of China[41890811];National Natural Science Foundation of China[42076047];National Natural Science Foundation of China[42106068];National Natural Science Foundation of China[42276064];

Geochemistry & Geophysics

Geochemistry & Geophysics

WOS:001078504900001

ELSEVIER

GEOSCIENCES

2-s2.0-85169834024

Scopus

1.School of Oceanography,Shanghai Jiao Tong University,Shanghai,200030,China
2.Key Laboratory of submarine Geosciences,Second Institute of Oceanography,Ministry of Natural Resources,Hangzhou,310012,China
3.State Key Laboratory of Lithospheric Evolution,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing,100029,China
4.Academy for Advanced Interdisciplinary Studies,Southern University of Science and Technology,Shenzhen,518055,China
5.Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai),Zhuhai,519082,China
6.School of Earth Sciences and Engineering,Sun Yat-sen University,Zhuhai,519082,China
7.Institute of Oceanology,Chinese Academy of Sciences,Qingdao,266071,China
8.Paleoceanography Research Interest Group,Faculty of Science and Marine Environment,Universiti Malaysia Terengganu,Kuala Nerus,Terengganu,21300,Malaysia
9.Donghai Laboratory,Zhejiang, Zhoushan,316021,China
10.Taihu Laboratory of Deepsea Technological Science,Wuxi,214028,China

Cheng，Liqun,Fang，Yinxia,Niu，Xiongwei,et al. Lithospheric velocity structure of South China Sea basin from ocean bottom seismometer ambient noise tomography[J]. Tectonophysics,2023,864.

Cheng，Liqun.,Fang，Yinxia.,Niu，Xiongwei.,Li，Tingzi.,Dong，Chongzhi.,...&Du，Xinguang.(2023).Lithospheric velocity structure of South China Sea basin from ocean bottom seismometer ambient noise tomography.Tectonophysics,864.

Cheng，Liqun,et al."Lithospheric velocity structure of South China Sea basin from ocean bottom seismometer ambient noise tomography".Tectonophysics 864(2023).