Abstract
This study examined the geochemical features of pore water in the diapiric area of the Yinggehai Basin, northwestern South China Sea, and illuminated the origin and evolution of basin fluids. Pore water with low salinity occurs in marine sediments in the diapiric area even without meteoric water infiltration. The presence of low-salinity water within deep, overpressured compartments is assumed to be due to smectite-illite transformation. Howerver, in shallow portions (less than 2 000 m) of diapiric areas with normal pressure, pore water has a much wider variation and much lower salinity than that in the overpressured intervals. Its total dissolved solid (TDS) content is ∼5 336 to 35 939 mg/L. Moreover, smectite and chlorite content sharply decreases as kaolinite and illite content increase in shallower intervals. The geochemical variation of pore water in diapiric structures indicates the expulsion of low-salinity, overpressured fluids along vertical faults. Strong injection of hot fluids from deep overpressured sediments results in rapid clay mineral transformation in shallow reservoirs. Consequently, fluid mixing due to fluid expulsion from deeper overpressured deposits leads to variation in salinity and ionic composition as well as some diagenetic reactions. This includes transformation of clay minerals caused by the higher temperatur of deeper hot fluids, e.g., the transfromation of smectite to illite and chlorite to kaolinite. Therefore, variations in salinity and ionic compositions in various pressured systems provide a clue to flow pathways and associated diagenetic reactions.
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References Cited
Bjørlykee, K., 1993. Fluid Flow in Sedimentary Basins. Sedimentary Geology, 86(1–2): 137–158. doi:10.1016/0037-0738(93)90137-T
Burley, S. D., MacQuaker, J. H. S., 2012. Authigenic Clays, Diagenetic Sequence and Conceptual Diagenetic Models in Contrasting Basin Margin and Basin Center, North Sea Jurassic Sandstones and Mudstones. In: Housekencht, D. W., Pittman, E. D., eds., Origin, Diagenesis and Petrophysics of Clay Minerals in Sandstones. SEPM Special Publication, 47: 81–110
Cai, C. F., Franks, S. G., Aagaard, P., 2001. Origin and Migration of Brines from Paleozoic Strata in Central Tarim, China: Constraints from 87Sr/86Sr, δD, δ18O, and Water Chemistry. Applied Geochemistry, 16: 1269–1284. doi:10.1016/S0883-2927(01)00006-3
Chen, P. H., Chen, Z. Y., Zhang, Q. M., 1993. Sequence Stratigraphy and Continental Margin Development of the Northwestern Shelf of the South China Sea. AAPG Bulletin, 77: 842–862
Dickey, P. A., Collins, A. G., Fajardo, I. I. M., 1972. Chemical Composition of Deep Formation Waters in Southwestern Louisiana. AAPG Bulletin, 56: 1530–1570
Gong, Z. S., Li, S. T., Xie, T. J., 1997. Continental Margin Basin Analysis and Hydrocarbon Accumulation of the Northern South China Sea. Science Press, Beijing. 193–256 (in Chinese with English Abstract)
Gonzalez, F., Moretti, I., Guichet, X., 2011. Formation Water Flow and Diagenesis in the Colombian Llanos Forland Basin. First Break, 29(10): 51–58. doi:10.3997/1365-2397.2011029
Hanor, J. S., 1987. Kilometer-Scale Thermohaline Overturn of Pore Waters in the Louisiana Gulf Coast. Nature, 327: 501–503
Hanor, J. S., 2001. Reactive Transport Involving Rock-Buffered Fluids of Verying Salinity. Geochimica et Cosmochimica Acta, 65(21): 3721–3732. doi:10.1016/S0016-7037(01)00703-7
Hao, F., Li, S. T., Gong, Z. S., et al., 2000. Thermal Regime, Interreservoir Compositional Heterogeneities, and Reservoir-Filling History of the Dongfang Gas Field, Yinggehai Basin, South China Sea: Evidence for Episodic Fluid Injections in Over-Pressured Basin. AAPG Bulletin, 84: 607–626
Huang, B. J., Xiao, X. M., Dong, W. L., 2002. Multiphase Natural Gas Migration and Accumulation and Its Relationship to Diaper Structures in the DF1-1 Gas Field, South China Sea. Marine and Petroleum Geology, 19(7): 861–872. doi:10.1016/S0264-8172(02)00109-5
Huang, B. J., Xiao, X. M., Li, X. X., 2003. Geochemistry and Origins of Natural Gases in the Yinggehai and Qiongdongnan Basins, Offshore South China Sea. Organic Geochemistry, 34(7): 1009–1025. doi:10.1016/S0146-6380(03)00036-6
Karsten, M., Bachu, S., 2002. Origin, Chemistry and Flow of Formation Waters in the Mississippian-Jurassic Sedimentary Succession in the West-Central Part of the Alberta Basin, Canada. Marine and Petroleum Geology, 19(3): 289–306. doi:10.1016/S0264-8172(02)00018-1
Land, L. S., 1995. Na-Ca-Cl Saline Formation Waters, Frio Formation (Oligocene), South Texas, USA: Products of Diagenesis. Geochimica et Cosmochimica Acta, 59(11): 2163–2174. doi:10.1016/0016-7037(95)00098-K
Land, L. S., MacPherson, G. L., 1992. Origin of Saline Formation Waters, Cenozoic Section, Gulf of Mexico Sedimentary Basin. AAPG Bulletin, 76(9): 1344–1362
Lei, C., Ren, J. Y., Clift, P. D., et al., 2011. The Structure and Formation of Diapirs in the Yinggehai-Song Hong Basin, South China Sea. Marine and Petroleum Geology, 28(5): 980–991. doi:10.1016/j.marpetgeo.2011.01.001
Li, S. T., Lin, C. S., Zhang, Q. M., et al., 1999. Episodic Rifting of Continental Marginal Basins and Tectonic Events since 10 Ma in the South China Sea. Chinese Science Bulletin, 44(1): 10–23
Lin, G. C., Nunn, J. A., 1997. Evidence for Recent Migration of Geopressured Fluids along Faults in Eugene Island, Block 330, Offshore Louisiana, from Estimates of Pore Water Salinity. Gulf Coast Association of Geological Societies Transactions, 47: 419–424
Losh, S., Walter, L., Meulbroek, P., et al, 2002. Reservoir Fluids and Their Migration into the South Eugene Island Block 330 Reservoirs, Offshore Louisiana. AAPG Bulletin, 86(8): 1463–1488
Lu, M., 1999. Reservoir Characteristics of the Gas-Bearing Area in Ying-Qiong Basin. Natural Gas Industry, 19(1): 20–24 (in Chinese with English Abstract)
Meng, F. J., Xiao, L. H., Xie, Y. H., et al., 2012. Abnormal Transformation of Clay Minerals in the Yinggehai Basin and Its Significance. Acta Sedimentologica Sinica, 30(3): 29–36 (in Chinese with English Abstract)
Moldovanyi, E. P., Walter, L. M., 1992. Regional Trends in Water Chemistry, Smackover Formation, Southwest Arkansas: Geochemical and Physical Controls. AAPG Bulletin, 76(6): 864–894
Morton, R. A., Land, L. S., 1987. Regional Variations in Formation Water Chemistry, Frio Formation (Oligocene), Texas Gulf Coast. AAPG Bulletin, 71(2): 191–206
Muggeridge, A., Abacioglu, Y., England, W., et al., 2004. Dissipation of Anomalous Pressures in the Subsurface. Journal of Geophysical Research, 109: B11104. doi:10.1029/2003JB002922
Parnell, J., 2002. Fluid Seeps at Continental Margins: Towards an Integrated Plumbing System. Geofluids, 2(2): 57–61. doi:10.1046/j.1468-8123.2002.00035
Petschick, R., Kuhn, G., Gingele, F., 1996. Clay Mineral Distribution in Surface Sediments of the South Atlantic: Sources, Transport, an Drelation to Oceanography. Marine Geology, 130(3–4): 203–229. doi:10.1016/0025-3227(95)00148-4
Ru, K., Pigott, J. D., 1986. Episodic Rifting and Subsidence in the South China Sea. AAPG Bulletin, 70(9): 1136–1155
Seewald, J. S., 2003. Organic-Inorganic Interactions in Petroleum-Producing Sedimentary Basins. Nature, 426: 327–333. doi:10.1038/nature0213
Wan, Z. F., Xia, B., Lü, B. F., et al., 2012. Yinggehai Basin Gas Exploration: Comparison with Jiyang Depression. Journal of Earth Science, 23(3): 359–372
Wilkinson, M., Darby, D., Haszeldine, R. S., et al., 1997. Secondary Porosity Generation during Deep Burial Associated with Overpressure Leak-Off: Fulmar Formation, United Kingdom Central Graben. AAPG Bulletin, 81(5): 803–813
Xie, X. N., Li, S. T., Dong, W. L., et al., 2001. Evidence for Hot Fluid Flow along Faults near Diapiric Structure of the Yinggehai Basin, South China Sea. Marine and Petroleum Geology, 18(6): 715–728. doi:10.1016/S0264-8172(01)00024-1
Xie, X. N., Li, S. T., He, H., et al., 2003. Seismic Evidence for Fluid Migration Pathways from an Overpressured Systems in the South China Sea. Geofluids, 3(4): 245–253. doi:10.1046/j.1468-8123.2003.00070.x
Xu, H., Sun, J., Liao, J., et al., 2012. Bioherm Petroleum Reservoir Types and Features in Main Sedimentary Basins of the South China Sea. Journal of Earth Science, 23(6): 828–841
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Jiang, T., Xie, X., Chen, H. et al. Geochemistry of pore water and associated diagenetic reactions in the diapiric area of Yinggehai Basin, northwestern South China Sea. J. Earth Sci. 26, 306–316 (2015). https://doi.org/10.1007/s12583-015-0526-y
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DOI: https://doi.org/10.1007/s12583-015-0526-y