Quick Search:       Advanced Search
LI Yanping,JIANG Shaoyong,YANG Tao. 2017. Br/Cl, I/Cl and chlorine isotopic compositions of pore water in shallow sediments: implications for the fluid sources in the Dongsha area, northern South China Sea. Acta Oceanologica Sinica, 36(4):31-36
Br/Cl, I/Cl and chlorine isotopic compositions of pore water in shallow sediments: implications for the fluid sources in the Dongsha area, northern South China Sea
利用孔隙水Br/Cl、I/Cl比和氯同位素组成来示踪南海北部东沙海域浅层流体来源
Received:December 19, 2015  Revised:May 05, 2016
DOI:10.1007/s13131-017-1013-3
Key words:halogen  chlorine isotope  pore water  Dongsha area
中文关键词:  卤族元素  氯同位素  沉积物孔隙水  东沙海域
基金项目:
Author NameAffiliationE-mail
LI Yanping Ministry of Education Key Laboratory for Coast and Island Development, School of Geographic and Oceanographic Sciences, Nanjing University, Nanjing 210093, China
Collaborative Innovation Center of South China Sea Studies, Nanjing 210093, China 
 
JIANG Shaoyong State Key Laboratory for Mineral Deposits Research, Department of Earth Sciences, Nanjing University, Nanjing 210093, China
State Key Laboratory of Geological Processes and Mineral Resources, Faculty of Earth Resources, China University of Geosciences, Wuhan 430074, China 
shyjiang@nju.edu.cn 
YANG Tao State Key Laboratory for Mineral Deposits Research, Department of Earth Sciences, Nanjing University, Nanjing 210093, China
Collaborative Innovation Center of South China Sea Studies, Nanjing 210093, China 
 
Hits: 2159
Download times: 1749
Abstract:
      The Dongsha area is one of the most promising target areas for gas hydrate exploration in the South China Sea (SCS). The study of pore water geochemistry has played a key role in Chinese gas hydrate exploration. Br/Cl, I/Cl and δ37Cl in pore water were applied here in tracing gas hydrate occurrence, chemical evolution of pore fluids and water/rock interactions in low temperature sediment environments. The samples were collected from Sites HD255PC and HD309PC in the Dongsha area in 2004. At Site HD255PC, we found the elevated Br/Cl, I/Cl and decreased SO4/Cl at the depth of 4-5 m, suggestive of a laterally migrated fluid probably generated from the gas hydrate occurrence. The range of δ37Cl is -0.54‰ to +0.96‰, and positive δ37Cl at 4-5 m interval should be related with different diffusion rates between 35Cl and 37Cl. At Site HD309PC, a laterally migrated fluid was also found at the depth of 3-4 m, with the Br/Cl two times to that of the seawater and decreased I/Cl, indicating the fluid has no relationship with the gas hydrate. In this site, the chlorine isotopic composition varies from -0.7‰ to +1.9‰. Extra high Br/Cl might relate with the deep generated fluid. At higher temperature and pressure, the Br/Cl of the fluid is elevated during the hydrous silicate formation, while positive δ37Cl is also associated with the same mechanism.
中文摘要:
      
HTML View Full Text   View/Add Comment  Download reader
Close