Abstract
Moho structure provides important clues for understanding crustal structure, isostatic state and magmatic flux from mantle to surface. Across-basin Moho structure of the South China Sea (SCS) is important for understanding crustal evolution mechanisms of both continental break-up and seafloor spreading processes. Southwest Sub-basin (SWSB) opened up the latest and has the closest continental margins, making it the best to study the across-basin structure. Multichannel seismic (MCS) reflection data of line NH973-1 that crosses SWSB in NW-SE direction were reprocessed in order to image Moho structure. In MCS data, Moho reflectors are observed in places, which were not revealed in prior researches. The Moho generally shows symmetric structure on both sides of the central rift valley (CRV) and with variations in crustal thickness. Around CRV, the Moho is 2 seconds depth in two-way travel time (TWTT) beneath the igneous basement, which corresponds to 7 km depth, indicating normal oceanic crustal accretion during the ending of seafloor spreading. Close to the continent-ocean boundary (COB), the Moho becomes shallow to 1 second depth in TWTT (3.5 km), implying strong crustal thinning towards the continent, probably because of poor magma supply at the beginning of seafloor spreading. At south COB, the Moho depth under the crust almost reaches zero, which could be explained as a result of exhumed mantle. In addition, two low-angle, deep-penetrating normal faults are observed at south COB. The faults cut across the Moho into the upper mantle, which may be attributed to lithospheric hyper-stretching at COB during continental break-up.
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Aghaei, O., Nedimovic, M. R., Carton, H., Carbotte, S. M., Canales, J. P., and Mutter, J. C., 2014. Crustal thickness and Moho character of the fast-spreading East Pacific Rise from 9°42′N to 9°57′N from poststack-migrated 3D MCS data. Geochemistry Geophysics Geosystems, 15: 634–657.
Aslanian, D., Moulin, M., Olivet, J. L., Unternehr, P., Matias, L., Bache, F., Rabineau, M., Nouze, H., Klingelheofer, F., Contrucci, I., and Labails, C., 2010. Brazilian and African passive margins of the central segment of the South Atlantic Ocean: Kinematic constraints. Tectonophysics, 468: 98–112.
Barckhausen, U., Engels, M., Franke, D., Ladage, S., and Pubellier, M., 2014. Evolution of the South China Sea: Revised ages for breakup and seafloor spreading. Marine and Petroleum Geology, 58: 599–611.
Boillot, G., Beslier, M. O., and Girardeau, J., 1995. Nature, Structure and Evolution of the Ocean-Continent Boundary: The Lesson of the West Galicia Margin (Spain). Springer, Netherlands, 219–229.
Briais, A., Patrizt, P., and Tapponier, P., 1993. Updated interpretation of magnetic anomalies and seafloor spreading stages in the South China Sea: Implications for the tertiary tectonic of Southeast Asia. Journal of Geophysical Research, 98: 6299–6328.
Cameselle, A. L., Ranero, C. R., Franke, D., and Barckhausen, U., 2015. The continent-ocean transition on the northwestern South China Sea. Basin Research, 29: 1–23.
Contreras, J., Zuhlke, R., Bowman, S., and Bechstadt, T., 2010. Seismic stratigraphy and subsidence analysis of the southern Brazilian margin (Campos, Santos and Pelotas Basins). Marine and Petroleum Geology, 27: 1952–1980.
Contrucci, I., Matias, L., Moulin, M., Geli, L., Klingelhofer, F., Nouze, H., Aslanian, D., Olivet, J. L., Rehault, J. P., and Sibuet, J. C., 2004. Deep structure of the West African continental margin (Congo, Zaire, Angola), between 5 degrees S and 8 degrees S, from reflection/refraction seismics andgravity data. Geophysical Journal International, 158: 529–553.
Cullen, A., Reemst, P., Henstra, G., Gozzard, S., and Ray, A., 2010. Rifting of the South China Sea: New perspectives. Petroleum Geoscience, 16: 273–282.
Ding, W., Franke, D., Li, J., and Steuer, S., 2013. Seismic stratigraphy and tectonic structure from a composite multi-channel seismic profile across the entire dangerous grounds, South China Sea. Tectonophysics, 582: 162–176.
Ding, W., Li, J., Clift, P. D., and IODP Expedition 349 Scientists, 2016. Spreading dynamics and sedimentary process of the Southwest Sub-basin, South China Sea: Constraints from multichannel seismic data and IODP Expedition 349. Journal of Asian Earth Sciences, 115: 97–113.
Dix, H. C., 1955. Seismic velocities from surface measurements. Geophysics, 20: 68–86.
Franke, D., 2013. Rifting, lithosphere breakup and volcanism: Comparison of magma-poor and volcanic rifted margins. Marine and Petroleum Geology, 43: 63–87.
Franke, D., Barckhausen, U., Baristeas, N., Engels, M., Ladage, S., Lutz, R., Montano, J., Pellejera, N., Ramos, E. G., and Schnabel, M., 2011. The continent-ocean transition at the southeastern margin of the South China Sea. Marine and Petroleum Geology, 28: 1187–1204.
Franke, D., Savva, D., Pubellier, M., Steuer, S., Mouly, B., Auxietre, J., Meresse, F., and Chamot-Rooke, N., 2013. The final rifting evolution in the South China Sea. Marine and Petroleum Geology, 58: 704–720.
Gao, J., Wu, S., McIntosh, K., Mi, L., Yao, B., Chen, Z., and Jia, L., 2015. The continent-ocean transition at the mid-northern margin of the South China Sea. Tectonophysics, 654: 1–19.
Geoffroy, L., 2005. Volcanic passive margins. Concise Review Geosciences, 337: 1395–1408.
Hall, R., 2002. Cenozoic geological and plate tectonic evolution of SE Asia and the SW Pacific: Computer-based reconstructions, model and animations. Journal of Asian Earth Sciences, 20: 353–431.
Hall, R., van Hattum, M. W. A., and Spakman, W., 2008. Impact of India-Asia collision on SE Asia: The record in Borneo. Tectonophysics, 451: 366–369.
Holbrook, W. S., Reiter, E. C., Purday, G. M., and Toksoz, M. N., 1992. Image of the Moho across the continent-ocean transition, United States east-coast. Geology, 20: 203–206.
Holloway, N. H., 1982. North Palawan Block, Philippines–Its relation to Asian Mainland and role in the evolution of South China Sea. American Association of Petroleum Geologists Bulletin, 66: 1355–1383.
Hopper, J. R., Funck, T., and Tucholke, B. E., 2007. Structure of the Flemish Cap margin, Newfoundland: Insights into mantle and crustal processes during continental breakup. In: Imaging, Mapping, and Modelling Continental Lithosphere Extension and Breakup. Karner, G. D., et al., eds., Geological Society of Lodon Special Publications, London, 47–61.
Hsu, S. K., Yeh, Y. C., Doo, W. B., and Tsai, C. H., 2004. New bathymetry and magnetic lineations identifications in the northernmost South China Sea and their tectonic implications. Marine Geophysical Research, 25: 29–44.
Hu, D., Zhou, D., Wu, X., He, M., Pang, X., and Wang, Y., 2009. Crustal structure and extension from slope to deepsea basin in the northern South China Sea. Journal of Earth Science, 20: 27–37.
Jian, Z., Larson, H. C., Zarikian, C. A., and the Expedition 368 Scientists, 2018. Expedition 368 Preliminary Report: South China Sea Rifted Margin. International Ocean Discovery Program, Texas, 1–54.
Karner, G. D., and Driscoll, N. W., 1999. Style, timing and distribution of tectonic deformation across the Exmouth Plateau, northwest Australia, determined from stratal architecture and quantitative basin modelling. Geological Society of London Special Publicatiions, 164: 271–311.
Kearey, P., Klepeis, K. A., and Vine, F. J., 2009. Global Tectonics. Third edition. Wiley-blackwell, United Kingdom, 1–482.
Kent, G. M., Harding, A. J., Orcutt, J. A., Detrick, R. S., Mutter, J. C., and Buhl, P., 1994. Uniform accretion of oceanic crust south of the Garrett transform at 14°42′S on the East Pacific Rise. Journal of Geophysical Research, 99: 9097–9116.
Korenaga, J., and Sager, W. W., 2012. Seismic tomography of Shatsky Rise by adaptive importance sampling. Journal of Geophysical Research, 117: 70–83.
Larsen, H. C., Mohn, G., Nirrengarten, M., and the Expeditions 367/368 Scientists, 2018. Rapid transition from continental breakup to oceanic crust at South China Sea rifted margin. Nature Geoscience, 11: 782–789.
Lei, C., and Ren, J., 2016. Hyper-extended rift systems in the Xisha Trough: Implications for extreme crustal thinning ahead of a propagating ocean of the South China Sea. Marine and Petroleum Geology, 77: 846–864.
Lei, C., Ren, J., Pang, X., Chao, P., and Han, X., 2018. Continental rifting and sediment infill in the distal part of the northern South China Sea in the Western Pacific region: Challenge on the present-day models for the passive margins. Marine and Petroleum Geology, 93: 166–181.
Li, C. F., Xu, X., Lin, J., Sun, Z., Zhu, J., Yao, Y., Zhao, X., Liu, Q., Kulhanek, D. K., Wang, J., Song, T., Zhao, J., Qiu, N., Guan, Y., Zhou, Z., Williams T., and IODP 349 shipboard scientists, 2014. Ages and magnetic structures of the South China Sea constrained by deep tow magnetic surveys and IODP Expedition 349. Geochemistry Geophysics Geosystems, 15: 4958–4983.
Li, J., 2011. Dynamics of the continental margins of South China Sea: Scientific experiments and research progresses. Chinese Journal of Geophysics, 54: 2993–3003 (in Chinese with English abstract).
Li, J., Ding, W., Wu, Z., Zhang, J., and Dong, C., 2012. The propagation of seafloor spreading in the southwestern sub-basin, South China Sea. Chinese Science Bulletin, 57: 1896–1905 (in Chinese with English abstract).
Lu, C., Hao, T., Lin, J., and Qiu, X., 2016. The role of rifting in the development of the continental margins of the southwest subbasin, South China Sea: Insights from an OBS experiment. Marine Geophysical Research, 38: 1–19.
Lu, C., Hao, T., Qiu, X., Zhao, M., and You, Q., 2011. A study on the deep structure of the northern part of southwest sub-basin from ocean bottom seismic data, South China Sea. Chinese Journal of Geophysics, 54: 3129–3138 (in Chinese with English abstract).
Manatschal, G., and Bernoulli, D., 1999. Architecture and tectonic evolution of nonvolcanic margins: Present-day Galicia and ancient Adria. Tectonics, 18: 1099–1119.
McIntosh, K., Lavier, L., an Avendonk, H., Lester, R., Eakin, D., and Liu, C., 2014. Crustal structure and inferred rifting processes in the northwest South China Sea. Marine and Petroleum Geology, 58: 612–626.
Menzies, M. A., Klemperer, S. L., Ebinger, C. J., and Baker, J., 2002. Characteristics of volcanic rifted margins. Special Paper of the Geological Society of America, 362: 1–14.
Mohriak, W. U., Mello, M. R., Dewey, J. F., Maxwell, J. R., 1990. Petroleum geology of the Campos Basin, offshore Brazil. Geological Society London Special Publications, 50: 119–141.
Mutter, J. C., and Carton, H. D., 2013. The Mohorovicic discontinuity in ocean basins: Some observations from seismic data. Tectonophysics, 609: 314–330.
Nedimovic, M. R., Carbotte, S. M., Harding, A. J., Detrick, R. S., Canales, J. P., Diebold, J. B., Kent, G. M., Tischer, M., and Babcock, J. M., 2005. Frozen magma lenses below the oceanic crust. Nature, 436: 1149–1152.
Peron-Pinvidic, G., and Manatschal, G., 2009. The final rifting evolution at deep magma-poor passive margins from Iberia-Newfoundland: A new point of view. International Journal of Earth Sciences, 98: 1581–1597.
Pichot, T., Delescluse, M., Chamot- Rooke, N., Pubellier, M., Qiu, Y., Meresse, F., Sun, G., Savva, D., Wong, K. P., Watremez, L., and Auxietre, J. L., 2013. Deep crustal structure of the conjugate margins of the SW South China Sea from wide-angle refraction seismic data. Marine and Petroleum Geology, 58: 627–643.
Prada, M., Sallares, V., Ranero, C. R., Guzman, M., Zitellini, N., Grevemeyer, I., de Franco, R., and Medoc Cruise Party, 2012. Deep structure of the Tyrrhenian Basin from 2-D joint refraction and reflection travel-time tomography of wide angle seismic data. EGU General Assembly 2012. Vienna, Austria, 10323.
Pubellier, M., and Morley, C. K., 2014. The basins of Sundaland (SE Asia): Evolution and boundary conditions. Marine and Petroleum Geology, 58: 555–578.
Qiu, X., Zhao, M., Ao, W., Lu, C., Hao, T., You, Q., Ruan, A., and Li, J., 2011. OBS survey and crustal structure of the Southwest Sub-basin and Nansha Block, South China Sea. Chinese Journal of Geophysics, 54: 3117–3128 (in Chinese with English abstract).
Replumaz, A., and Tapponnier, P., 2003. Reconstruction of the deformed collision zone between India and Asia by backward motion of lithospheric blocks. Journal of Geophysical Research, 108: 2285–2309.
Reston, T., 2007. Extension discrepancy at North Atlantic non-volcanic rifted margins: Depth-dependent stretching or unrecognized faulting? Geology, 35: 367–370.
Rohr, K. M. M., Milkereit, B., and Yorath, C. J., 1988. Asymmetric deep crustal structure across the Juan de Fuca Ridge. Geology, 16: 533–537.
Ruan, A., Niu, X., Qiu, X., Li, J., Wu, Z., Zhao, M., and Wei, X., 2011. A wide angle ocean bottom seismometer profile across Liyue Bank, the southern margin of South China Sea. Chinese Journal of Geophysics, 54: 3139–3149 (in Chinese with English abstract).
Ruan, A., Wei, X., Niu, X., Zhang, J., Dong, C., Wu, Z., and Wang, X., 2016. Crustal structure and fracture zone in the central basin of the South China Sea from wide angle seismic experiments using OBS. Tectonophysics, 688: 1–10.
Sandwell, D. T., and MacKenzie, K. R., 1989. Geoid height versus topography for oceanic plateaus and swells. Journal of Geophysical Research, 94: 7403–7418.
Sandwell, D. T., and Smith, W. H. F., 1997. Marine gravity anomaly from Geosat and ERS-1 satellite altimetry. Journal of Geophysical Research, 102: 10039–10054.
Savva, D., Meresse, F., Pubellier, M., Chamot- Rooke, N., Lavier, L., Wong, P. K., Franke, D., Steuer, S., Sapin, F., Auxietre, J. L., and Lamy, G., 2013. Seismic evidence of hyper-stretched crust and mantle exhumation offshore Vietnam. Tectonophysics, 608: 72–83.
Skogseid, J., 2001. Volcanic margins: Geodynamic and exploration aspects. Marine and Petroleum Geology, 18: 457–461.
Smith, W. H. F., and Sandwell, D. T., 1997. Global seafloor topography from satellite altimetry and ship depth soundings. Science, 277: 1957–1962.
Song, T., and Li, C., 2015. Rifting to drifting transition of the southwest subbasin of the South China Sea. Marine Geophysical Research, 36: 167–185.
Steinhart, J. S., 1967. Mohorovicic discontinuity. In: International Dictionary of Geophysics, Volume 2. Runcorn, S. K., ed., Pergamon Press, Oxford, 991–994.
Sun, Z., Stock, J., Klaus, A., and the Expedition 367 Scientists, 2018. Expedition 367 Preliminary Report: South China Sea Rifted Margin. International Ocean Discovery Program, Texas, 1–33.
Taylor, B., and Hayes, D. E., 1980. The tectonic evolution of the South China Sea Basin. In: The Tectonic and Geologic Evolution of Southeast Asian Seas and Islands. Hayes, D. E., ed., American Geophysical Union Geophysical Monograph, Washington, D. C., 89–104.
Taylor, B., and Hayes, D. E., 1983. Origin and history of the South China Sea Basin. In: The Tectonic and Geologic Evolution of Southeast Asian Seas and Islands: Part 2. Hayes, D. E., ed., American Geophysical Union Geophysical Monograph, Washington, D. C., 23–56.
Tucholke, B. E., and Sibuet, J. C., 2007. Leg 210 synthesis: Tectonic, magmatic, and sedimentary evolution of the Newfoundland-Iberia Rift. Proceedings of the Ocean Drilling Program Scientific Results 210, 1–56.
Wang, Y., Qiu, Y., Yan, P., Zheng, H., Liu, H., and Wang, J., 2016. Seismic evidence for Mesozoic strata in the northern Nansha waters, South China Sea. Tectonophysics, 677: 190–198.
Whitmarsh, R. B., Minshull, T. A., Russell, S. M., Dean, S. M., Louden, K. E., and Chian, D., 2001. The role of syn-rift magmatism in the rift-to-drift evolution of the West Iberia continental margin: Geophysical observations. Geological Society London Special Publications, 187: 107–124.
Wu, Z., Li, J., Ruan, A., Lou, H., Ding, W., Niu, X., and Li, X., 2012a. Curstal structure of the Northwestern Sub-basin, South China Sea: Results from a wide-angle seismic experiment. Science China–Earth Sciences, 55: 159–172.
Wu, Z., Ruan, A., Li, J., Li, S., Qiu, X., and Ding, W., 2012b. Wide-angle seismic exploration in the Southwest Sub-basin of the South China Sea. Journal of Tropical Oceanography, 31: 35–39 (in Chinese with English abstract).
Xia, S., Zhao, D., Sun, J., and Huang, H., 2016. Teleseismic imaging of the mantle beneath southernmost China: New insights into the Hainan plume. Gondwana Research, 36: 46–56.
Yan, P., Deng, H., Liu, H., Zhang, Z., and Jiang, Y., 2006. The temporal and spatial distribution of volcanism in the South China Sea region. Journal of Asian Earth Science, 27: 647–659.
Yao, B., and Wang, G., 1983. Crustal structure of South China Sea Basin. Science China, 2: 177–186 (in Chinese with English abstract).
Yu, Z., Li, J., Ding, W., Zhang, J., Ruan, A., and Niu, X., 2017. Crustal structure of the southwest subbasin, South China Sea, from wide-angle seismic tomography and seismic reflection imaging. Marine Geophysical Research, 38: 85–104.
Zhang, J., Li, J., Ruan, A., Wu, Z., Yu, Z., Niu, X., and Ding, W., 2016a. The velocity structure of a fossil spreading centre in the Southwest Sub-basin, South China Sea. Geological Journal, 51: 548–561.
Zhang, J., Sager, W. W., and Korenaga, J., 2016b. The seismic Moho structure of Shatsky Rise oceanic plateau, northwest Pacific Ocean. Earth Planetary Science Letters, 441: 143–154.
Zhao, C., Song, H., Li, J., Song, Y., and Tian, L., 2011. Tectonic and seismic interpretation of line NH973-1 along Southwest Sub-basin in South China Sea. Chinese Journal of Geophysics, 54: 3258–3268 (in Chinese with English abstract).
Acknowledgments
We thank the scientists, crew, and technical staff of R/V Tanbao for collecting the seismic data. The research data used were provided by the National 973 Research Project of China and professor Pin Yan. We thank Xu Zhao for assistance in data processing and Yiming Luo for geographic plotting. This research was supported by the National Key R&D Program of China (No. 2018YFC03098 00), the National Natural Science Foundation of China (Nos. 91328205, 41376062, 91628301, U1606401, 4160 6 069, 41776058), the Natural Science Foundation of Guangdong Province in China (Nos. 2015A030310374, 2017A 030313243), the Chinese Academy of Sciences (Nos. Y4S L021001, QYZDY-SSW-DQC005) and the China Association of Marine Affairs (No. CAMAZD201714).
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Zhang, J., Chen, J. & Huang, Y. Moho Structure of the Southwest Sub-Basin, South China Sea, from a Multichannel Seismic Reflection Profile NH973-1. J. Ocean Univ. China 18, 1105–1114 (2019). https://doi.org/10.1007/s11802-019-3983-6
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DOI: https://doi.org/10.1007/s11802-019-3983-6