南海北部深海浅层沉积物中甲烷生物地球化学过程数值模拟研究

吴雪停; 刘丽华; Matthias Haeckel; 吴能友

doi:10.16562/j.cnki.0256-1492.2016.03.008

南海北部深海浅层沉积物中甲烷生物地球化学过程数值模拟研究

1. 中国科学院天然气水合物重点实验室, 中国科学院广州能源研究所, 广州 510640;
2. 中国科学院大学, 北京 100049;
3. 德国亥姆霍兹基尔海洋研究中心(GEOMAR), 基尔D-24148;
4. 国土资源部天然气水合物重点实验室, 青岛海洋地质研究所, 青岛 266071;
5. 海洋国家实验室海洋矿产资源评价与探测技术功能实验室, 青岛 266071

基金项目:

国家自然科学基金面上项目(41376076)；广东省基金自由申请项目(2015A030313718)；中国科学院对外合作重点项目(GJHZ1404)

详细信息

作者简介:
吴雪停(1989-),女,硕士生,主要从事海洋沉积物早期成岩作用研究,E-mail:wuxt@ms.giec.ac.cn

中图分类号: P744.4
计量
- 文章访问数: 2386
- HTML全文浏览量: 291
- PDF下载量: 44
出版历程
- 收稿日期: 2016-01-23
- 修回日期: 2016-03-23

SIMULATION OF THE BIOGEOCHEMICAL PROCESSES IN METHANE-BEARING SURFACE SEDIMENTS OF HAIYANG 4 AREA, NORTHERN SLOPE OF SOUTH CHINA SEA

1. Key Laboratory of Gas Hydrate, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China;
2. University of Chinese Academy of Sciences, Beijing 100049, China;
3. GEOMAR Helmholtz Centre for Ocean Research, KielD-24148, Germany;
4. The Key Laboratory of Gas Hydrate, Ministry of Land and Resources, Qingdao Institute of Marine Geology, Qingdao 266071, China;
5. Laboratory for Marine Mineral Resources, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China

摘要

摘要: 富甲烷浅层海相沉积物中的生物地球化学过程已引起了国内外学者的广泛关注。研究采用数值模拟的方法对"海洋四号区"浅层沉积物中甲烷生物地球化学过程进行定量研究。依据研究区域实际地质资料,使用Mathematica建立起一维反应运移稳态模型。模拟结果认为研究区深层沉积物内赋存有甲烷源,释放的甲烷气以气泡的形式运移至沉积物表层,并造成气泡淋滤现象。气泡淋滤使孔隙水中SO₄^2-等溶质浓度在海底以下0~2.8 m的范围内保持不变。甲烷气泡在浓度梯度作用下向孔隙水中溶解,溶解通量为160 mmol·m^-2·a^-1,溶解甲烷在微生物作用下被SO₄^2-氧化,氧化速率为140 mmol·m^-2·a^-1。甲烷通量与氧化速率均远小于水合物脊等甲烷渗漏活跃地区,SMTZ埋藏也相对较深,故推测甲烷源埋藏较深或规模较小,也有可能是良好的圈闭条件阻止了甲烷逸出。作为AOM过程的重要自生矿物,本地区碳酸盐和硫化物矿物沉淀速率都比较低(分别为35 mmol·m^-2·a^-1和70 mmol·m^-2·a^-1),且碳酸盐的沉淀受到了硫化物矿物的影响。
- 海洋浅层沉积物 /
- AOM /
- 自生碳酸盐岩 /
- 数值模拟
Abstract: The biogeochemical processes in the methane-bearing surface sediments have been an interesting research field worldwide. Numerical simulation method is used in this study to quantify the biogeochemical processes in methane-bearing surface sediments of the Haiyang 4 Area, northern slope of the South China Sea. According to the actual geological data in the study area, a numerical transport-reaction model has been developed with Mathematica. According to the simulation results, it is inferred that there are methane sources in the study area. Methane could be rapidly transported to the surface sediments as gas bubbles from the methane reservoir in deep sediments. Gas irrigation could drive the exchange of solutes which led to the similarity of sulfate concentrations in the upper 0~2.8 m to those in the bottom water. The small inflow of methane from below (160 mmol·m^-2·a^-1) induces the low reactive rate of anaerobic methane oxidation (AOM) of 140 mmol·m^-2·a^-1 and a low carbonate precipitation rate of 35 mmol·m^-2·a^-1. This may be caused by a small or deep methane reservoir in the sediments. The well trap conditions can also prevent the escaping of methane. The precipitation rates of carbonate and sulfide turned out to be small in this area. The simulation also revealed that when the rate of sulfide mineral precipitation is high, the rate of carbonate precipitation will be diminished due to the alkalinity reduction.
- benthic surface sediments /
- AOM /
- authigenic carbonate /
- numerical simulation

HTML全文

参考文献(42)

[1]	Jorgensen B B, Revsbech N P. Oxygen uptake, bacterial distribution, and carbon-nitrogen-sulfur cycling in sediments from the Baltic Sea-North Sea transition[J]. Ophelia, 1989. 31(1):29-49.
[2]	Arndt S, Jφrgensen B B, LaRowe D E, et al. Quantifying the degradation of organic matter in marine sediments:A review and synthesis[J]. Earth-Science Reviews, 2013, 123:53-86.
[3]	Reeburgh W S. Oceanic methane biogeochemistry[J]. Chemical Reviews, 2007, 107(2):486-513.
[4]	Luff R, Wallmann K, Grandel S, et al. Numerical modeling of benthic processes in the deep Arabian Sea[J]. Deep-Sea Research Part Ii-Topical Studies in Oceanography, 2000, 47(14):3039-3072.
[5]	Hinrichs K U, Hayes J M, Sylva S P, et al. Methane-consuming archaebacteria in marine sediments[J]. Nature, 1999, 398(6730):802-805.
[6]	Bach W, Paull C K, Ussler W. Marine pore-water sulfate profiles indicate in situ methane flux from underlying gas hydrate[J]. Geology of Ore Deposits, 1996, 24(7):655-658.
[7]	Luff R, Wallmann K. Fluid flow, methane fluxes, carbonate precipitation and biogeochemical turnover in gas hydrate-bearing sediments at Hydrate Ridge, Cascadia Margin:Numerical modeling and mass balances[J]. Geochimica et Cosmochimica Acta, 2003, 67(18):3403-3421.
[8]	Feng D, Chen D F, Peckmann J, et al. Authigenic carbonates from methane seeps of the northern Congo fan:Microbial formation mechanism[J]. Marine and Petroleum Geology, 2010, 27(4):748-756.
[9]	Karaca D, Hensen C,Wallmann K. Numerical modeling of Ca-enrichment on authigenic carbonate formation at mud volcanoes:A case study off Costa Rica[J]. Geochimica et Cosmochimica Acta, 2008, 72(12):A450-A450.
[10]	Luff R, Greinert J, Wallmann K, et al. Simulation of long-term feedbacks from authigenic carbonate crust formation at cold vent sites[J]. Chemical Geology, 2005, 216(1-2):157-174.
[11]	Luff R, Wallmann K, Aloisi G. Numerical modeling of carbonate crust formation at cold vent sites:significance for fluid and methane budgets and chemosynthetic biological communities[J]. Earth and Planetary Science Letters, 2004, 221(1-4):337-353.
[12]	Haeckel M, Boudreau B P, Wallmann K. Bubble-induced porewater mixing:A 3-D model for deep porewater irrigation[J]. Geochimica et Cosmochimica Acta, 2007, 71(21):5135-5154.
[13]	管红香,陈多福,宋之光. 冷泉渗漏区海底微生物作用及生物标志化合物[J]. 海洋地质与第四纪地质, 2007,27(5):75-83. [GUAN Hongxiang, CHEN Duofu, SONG Zhiguang. Biomarkers and bacterial processes in the sediments of gas seep site[J]. Marine Geology and Quaternary Geology, 2007, 27(5):75-83.]
[14]	Han X, Suess E, Liebetrau V, et al. Past methane release events and environmental conditions at the upper continental slope of the South China Sea:constraints by seep carbonates[J]. International Journal of Earth Sciences, 2014, 103(7):1873-1887.
[15]	Tong H P, Feng D, Cheng H, et al. Authigenic carbonates from seeps on the northern continental slope of the South China Sea:New insights into fluid sources and geochronology[J]. Marine and Petroleum Geology, 2013, 43:260-271.
[16]	Liu L, Wu N. Simulation of advective methane flux and AOM in Shenhu area, the northern South China Sea[J]. Environmental Earth Sciences, 2014, 71(2):697-707.
[17]	黄永祥, Suess E, 吴能友,等. 南海北部陆坡甲烷和天然气水合物地质-中德合作SO-177航次成果专报[M]. 北京:地质出版社, 2008.[HUANG Yongxiang, Suess E, WU Nengyou, et al.Mehtane and Gas Hydrate Geology of the Northern South China Sea:Sino-German Cooperative SO-177 Cruise Report[M]. Beijing:Geological Publishing House, 2008.]
[18]	龚跃华, 吴时国,张光学,等.南海东沙海域天然气水合物与地质构造的关系[J]. 海洋地质与第四纪地质, 2008, 28(1):99-104. [GONG Yuehua, WU Shiguo,ZHANG Guangxue, et al. Relation between gas hydrate and geologic structures in Dongsha islands sea area of South China Sea[J]. Marine and Petroleum Geology,2008, 28(1):99-104]
[19]	陆红锋,陈芳,刘坚,等. 南海北部神狐海区的自生碳酸盐岩烟囱-海底富烃流体活动的记录[J]. 地质论评, 2006, 52(3):352-357. [LU Hongfeng, CHEN Fang, LIU Jian, et al. Characteristics of authigenic carbonate chimneys in Shenhu Area, Northern South China Sea:Recorders of hydrocarbon-enriched fluid activity[J].Geological Review, 2006, 52(3):352-357.]
[20]	陆红锋,刘坚,陈芳,等. 南海台西南区碳酸盐岩矿物学和稳定-天然气水合物存在的主要证据之一[J]. 地学前沿, 2005, 12(3):268-276. [LU Hongfeng, LIU Jian, CHEN Fang,et al.Mineralogy and stable isotopic composition of authigenic carbonates in bottom sediments in the offshore area of southwest Taiwan, South China Sea:Evidence for gas hydrates occurrence[J]. Earth Science Frontiers, 2005, 12(3):268-276.]
[21]	陈胜红,贺振华,何家雄,等. 南海东北部边缘台西南盆地泥火山特征及其与油气运聚关系[J]. 天然气地球科学, 2009, 20(6):872-878. [CHEN Shenghogn, HE Zhenhua,HE Jiaxiong,et al.The characters of the mud volcanoes in the North-east marginal of the South China Sea and the relationship with the accumulation and migration of oil and gas[J]. Natural Gas Geoscience,2009, 20(6):872-878.]
[22]	邬黛黛,吴能友,张美. 东沙海域SMI与甲烷通量的关系及对水合物的指示[J]. 地球科学-中国地质大学学报, 2013, 38(6):1309-1320. [WU Daidai, WU Nengyou, ZHANG Mei, et al. Relationship of sulfate-methane interface(SMI), methane flux and the underlying gas hydrate in Dongsha Area, Northern South China Sea[J].Earth Science-Journal of China University of Geosciences, 2013, 38(6):1309-1320.]
[23]	Fossing H, Ferdelman T G, Berg P. Sulfate reduction and methane oxidation in continental margin sediments influenced by irrigation (South-East Atlantic off Namibia)[J]. Geochimica et Cosmochimica Acta, 2000, 64(5):897-910.
[24]	苏新,陈芳,陆红锋,等. 南海北部深海甲烷冷泉自生碳酸盐岩显微结构特征与流体活动关系初探[J]. 现代地质, 2008, 22(3):376-381. [SU Xin, CHEN Fang, LU Hongfeng, et al.Micro-textures of methane seep carbonates from the Northern South China Sea in correlation with fluid flow[J]. Geoscience, 2008, 22(3):376-381.]
[25]	于晓果,韩喜球,李宏亮,等. 南海东沙东北部甲烷缺氧氧化作用的生物标志化合物及其碳同位素组成[J]. 海洋学报, 2010, 30(3):77-84. [YU Xiaoguo, HAN Xiqiu, LI Hongliang, et al. Biomarkers and carbon isotope composition of anaerobic oxidation of methane in sediments and carbonates of northeastern part of Dongsha, South China Sea[J]. Acta Oceanologica Sinica, 2008, 30(3):77-84.]
[26]	Luo M, Dale A W, Wallmann K, et al. Estimating the time of pockmark formation in the SW Xisha Uplift (South China Sea) using reaction-transport modeling[J]. Marine Geology, 2015, 364:21-31.
[27]	Suess E. F S Sonne Fahrtbericht/Cruise Report SO177 SiGer 2004, Sino-German Cooperative Project:South China Sea Continental Margin:Geological Methane Budget and Environmental Effects of Methane Emissions and Gashydrates[M]. IFM-GEOMAR Report, 2005.
[28]	Wang P P W, Blum P. Proceedings of the Ocean Drilling Program:Initial Reports 184[M]. Texas A&M, College Station, USA, 2000.
[29]	Chuang P-C, Dale A W, Wallmann K, et al. Relating sulfate and methane dynamics to geology:Accretionary prism offshore SW Taiwan[J]. Geochemistry Geophysics Geosystems, 2013, 14(7):2523-2545.
[30]	Boudreau B P. Diagenetic Models and Their Implementation[M]. Springer Berlin.1997.
[31]	Duan Z H, Moller N, Greenberg J, et al. The prediction of methane solubility in antural waters to high ionic strength from 0 to 250℃ and from 0 to 1600 bar[J]. Geochimica et Cosmochimica Acta, 1992, 56(4):1451-1460.
[32]	Haeckel M, Suess E, Wallmann K, et al. Rising methane gas bubbles form massive hydrate layers at the seafloor[J]. Geochimica et Cosmochimica Acta, 2004, 68(21):4335-4345.
[33]	Blair N E, Aller R C. Anaerobic methane oxidation on the Amazon Shelf[J]. Geochimica et Cosmochimica Acta, 1995, 59(21):4564-4564.
[34]	Boetius A, Ravenschlag K, Schubert, C J. A marine microbial consortium apparently mediating anaerobic oxidation of methane[J]. Nature, 2000, 407:623-626.
[35]	Millero F J. Thermodynamics of the carbon-dioxide system in the oceans[J]. Geochimica et Cosmochimica Acta, 1995, 59(4):661-677.
[36]	Kristensen E, Penha-Lopes G, Delefosse M, et al. What is bioturbation? The need for a precise definition for fauna in aquatic sciences[J]. Marine Ecology Progress Series, 2012, 446:285-302.
[37]	Schulz H D, Dahmke A, Schinzel U, et al. Early diagenetic processes,fluxes,and reaction-rates in sediments of the South-Atlantic[J]. Geochimica et Cosmochimica Acta, 1994, 58(9):2041-2060.
[38]	Niewohner C, Hensen C, Kasten S, et al. Deep sulfate reduction completely mediated by anaerobic methane oxidation in sediments of the upwelling area off Namibia[J]. Geochimica Et Cosmochimica Acta, 1998, 62(3):455-464.
[39]	Anderson A L, Abegg F, Hawkins J A, et al. Bubble populations and acoustic interaction with the gassy floor of Eckernforde Bay[J]. Continental Shelf Research, 1998, 18(14-15):1807-1838.
[40]	Paull C K, Dallimore S R, Caress D W, et al. Active mud volcanoes on the continental slope of the Canadian Beaufort Sea[J]. Geochemistry Geophysics Geosystems, 2015, 16(9):3160-3181.
[41]	Boudreau B P, Algar C, Johnson B D, et al. Bubble growth and rise in soft sediments[J]. Geology, 2005, 33(6):517-520.
[42]	Albert D B, Martens C S, Alperin M J. Biogeochemical processes controlling methane in gassy coastal sediments-Part 2:groundwater flow control of acoustic turbidity in Eckernforde Bay Sediments[J]. Continental Shelf Research, 1998, 18(14-15):1771-1793.