浅表层天然气水合物区的海底地形特征——以鄂霍次克海为例

摘要/Abstract

摘要：

使用重力取样器、渔网、深潜器等手段已经在海底及以下浅表层区域采获天然气水合物样品。但关于浅表层水合物的发育机制、分布规律及与海底地形的关系等问题还缺乏基本认识。根据2006年鄂霍次克海天然气水合物调查航次的调查数据，介绍了浅表层天然气水合物区的海底地形特征。萨哈林东北陆坡区，特别是中、下陆坡区发育大量海底凸起,这些凸起一般呈不对称的丘形，宽几百米，高几十米。不同于海底沙波、沙脊，海底凸起为孤立海底地形，在南北方向上并不连续。海底凸起和浅表层天然气水合物的发育密切相关。在海底剖面仪测量结果剖面上清楚地显示古陆坡凸起的发育。普遍地，现今海底陆坡凸起的幅度要小于古陆坡凸起的幅度，个别地方古、今陆坡凸起的形态有所变化，但大部分古、今陆坡凸起是一一对应的，基本形态没有根本变化。在萨哈林陆坡地区存在两个方向的挤压应力场，分别是由德鲁根盆地向萨哈林陆坡方向的挤压应力场、萨哈林陆坡沿萨哈林走滑断裂向南的挤压应力场。海底陆坡凸起是这两大应力场复合作用的结果。浊反射区中的游离气是底辟构造中的超高压多相物质向上迁移形成的。浊反射区上方对应的海底凸起应该是宏观构造挤压和局部底辟发育叠合的结果。浊反射区上方的海底凸起，在形态等方面应该和其他仅由挤压构造原因形成的凸起有所区别，比如顶部发育裂口等。在底辟构造中，由于游离气体的向上迁移，在整个水合物稳定域中从下到上，直至海底都可能形成水合物，从而使我们有机会使用重力采样器这样的设备也能采获天然气水合物样品。

关键词: 浅表层水合物, 海底地形, 陆坡凸起, 底辟, 浊反射

Abstract:

Shallow gas hydrates had already been retrieved by gravity corer, busyness fishing net, and submersible machine on the sea floor and in the sediment near to the sea floor. However the formation mechanism of shallow gas hydrate, distribution of shallow gas hydrate, and also the relationship between shallow gas hydrate and sea floor topography still remain unclear. Based on the side scan sonar and sub-bottom profile data from 2006 gas hydrate cruise in the area of Okhotsk Sea, the paper found that shallow gas hydrates closely related to the dome structures. The dome structures were commonly found on the slope, especially along the Middle and Lower Sakhalin Slope which were about several hundred meters wide and several ten meters high. Different from sea floor sand waves and sand ridges, the dome structures were isolated structures but with a slightly longer and lower wing than that of the upper wing. Sub-bottom profile recorder also showed that buried dome structures also very well developed on the slope beneath a 30 cm modern sediment layer. A joint compress stress field from Deryugin basin to the Sakhalin Slope and also from north Sakhalin Slope to the South Sakhalin Slope along the strike slip fault along Sakhalin Slope was the main cause of the formation of the dome structures, and also the main cause of the diapir structures among the dome structures. Acoustic turbidity beneath the diapir structures clearly show the migration of free gases from deep to the gas hydrate stability zone and to the sea water body from the mini crater on top of the dome structure. Gas hydrates were formed due to the availability of free gas within the diapir structures from the bottom of gas hydrate stability zone up to the sea floor.

中图分类号:

P737.1

栾锡武,岳保静. 浅表层天然气水合物区的海底地形特征——以鄂霍次克海为例[J]. 现代地质, 2008, 22(3): 420-429.

LUAN Xi-wu,YUE Bao-jing. Sea Floor Topography of Shallow Gas Hydrate Area:Data from Okhotsk Sea[J]. Geoscience, 2008, 22(3): 420-429.

参考文献

［1］Sloan E D. Clathrate Hydrates of Natural Gases［M］.New York：Marcel Dekker，1990:641.

［2］Kvenvolden K A. Gas hydrategoelogical perspective and global change［J］. Rev Geophys, 1993, 31:173-187.

［3］MacDonald G T. The future of methane as an energy resource［J］.Annu Rev Energy, 1990，15:53-83.

［4］Milkov A V, Claypool G E, Lee Y J, et al. ODP Leg 204 Scientific Party，in situ methane concentrations at Hydrate Ridge Offshore Oregon: new constraints on the global gas hydrate inventory from an active margin［J］. Geology, 2003, 31:833-836.

［5］Riedel M, Long P E, Collett T S. Estimates of in situ gas hydrate concentration from resistivity monitoring of gas hydrate bearing

sediments during temperature equilibration［J］. Marine Geology, 2006, 227:215-225.

［6］Shoji H，Soloviev V，Matveeva T. Hydratebearing structures in the Sea of Okhotsk［J］. EOS, 2005, 86:13-24.

［7］Hyndman R D, Dallimore R S. Natural gas hydrate studies in Canada［J］. Canadian Society of Exploration Geophysicists, 2001, 26:11-20.

［8］Torres M E, Bohrmann G, Brown K, et al. Geochemical observations on Hydrate Ridge, Cascadia Margin during R/VATLANTISCruise AT3-35b, July 1999［R］. Oregon State University,1999.

［9］Dallimore S R, Collett T S. Scientific results from the Mallik 2002 gas hydrate production research well program, Mackenzie Delta,

Northwest Territories, Canada［J］. Geological Survey of Canada Bulletin, 2005, 585:1-140.

［10］栾锡武，赵克斌，孙冬胜，等.天然气水合物的开采——以马利克钻井为例［J］.地球物理学进展，2007，22（4）：1295-1304.

［11］Suess E, Torres M E, Bohrmann. Sea Floor Methane Hydrates at Hydrate Ridge, Cascadia margin, in Natural Gas Hydrates:

Occurrence, Distribution and Detection ［M］. Washington D C: American Geophysical Union, 2001: 99-113.

［12］Francisca F, Yun T S, Ruppel C,et al. Geophysical and geotechnical properties of nearseafloor sediments in the northern Gulf of Mexico gas hydrate province［J］. Earth and Planetary Science Letters, 2005, 237(3-4）: 924-939.

［13］Charlou J L, Donval J P, Fouquet Y, et al. Physical and chemical characterization of gas hydrates and associated methane plumes in the CongoAngola Basin ［J］. Chemical Geology,2004，205（3-4）:405-425.

［14］Kudelkin V V, Savitskiy V O, Karpey T I. Structure and evolution of the sediment cover of the near Sakhalin areas of the SouthOkhotsk Basin［J］. Geol Pac Ocean, 1986, 4: 3-13.

［15］Ternois Y, Kawamura K, Keigwin L. A biomarker approach for assessing marine and terrigenous inputs to the

sediments of Sea of Okhotsk for the last 27,000 years［J］. Geochimica et Cosmochimica Acta, 2001, 65（5）:791-802.

［16］Gorbarenko S A, Southon J R, Keigwin L D. Late PleistoceneHolocene oceanographic variability in the Okhotsk Sea: geochemical, lithological and paleontological evidence［J］.Palaeogeography,Palaeoclimatology,Palaeoecology,2004,209:281-301.

［17］Seki O, Yoshikawa C, Nakatsuka T. Fluxes, source and transport of organic matter in the western Sea of Okhotsk: Stable carbon isotopic ratios of nalkanes and total organic carbon［J］.Deep Sea Research Part I:Oceanographic Research Papers,2006, 53:253-270.

［18］Bogdanov N A, Chekhovich V D. On collision between the West Kamchatka and Sea of Okhotsk Plate［J］. Geotectonics, 2002, 36:72-85.

［19］Rozhdestvenskiy S S. Evolution of the Sakhalin folds system［J］. Tectonophysics, 1986, 127:331-339.

［20］Ludmann T, Wong H K. Characteristics of gas hydrate occurrences associated with mud diapirism and gas escape structures

in the northwestern Sea of Okhotsk［J］. Marine Geology，2003,201:269-286.

［21］Shakirov R, Obzhirov A, Suess E. Mud volcanoes and gas vents in the Okhotsk Sea area［J］. GeoMarine Letters, 2004, 24: 140-149.

［22］栾锡武，赵克斌，孙东胜，等.鄂霍次克海天然气水合物的成藏条件分析［J］.海洋地质与第四纪地质，2006，23（6）：55-68.

［23］Jin Y K, Obzhirov A, Shoji H, et al. CHAOS III Project Cruise Report: RV Akademik M A Lavrentiev Cruise 39, May 24-June 18, 2006[M]. Incheon: KORPRI, 2007:132.

［24］Garcia Gil S, Vilas F, Garcia Garcia A. Shallow gas features in incised valley fills（Ria de Vigo, NW Spain）: A case study［J］. Continental Shelf Research, 2002, 22: 2303-2315.

［25］Fannin N G T. The use of regional geological surveys in the North Sea and adjacent areas in recognition of offshore hazards［M］// Ardus D A. Offshore Site Investigation. London: Graham & Trotman, 1980: 5-21.

［26］王海荣，王英民，丘燕，等.南海北部大陆边缘深水环境的沉积物波［J］.自然科学进展，2007，17（9）：1235-1243.

［27］钟广法，李前裕，郝沪军，等.深水沉积物波及其在南海研究之现状［J］.地球科学进展，2007，22（9）：907-913.

［28］刘家喧.台湾海域新生代的大地构造［M］//黄奇瑜.台湾大地构造.台北：中国地质学会，2002：1-48.

［29］李家彪，金翔龙，阮爱国，等.马尼拉海沟增生楔中段的挤入构造［J］.科学通报，2004，49（10）：1000-1008.

［30］李家彪，金翔龙，高金耀.南海东部海盆晚期扩张的构造地貌研究［J］.中国科学（D辑），2002，32（3）：239-248.

［31］彭学超，吴庐山，崔兆国，等.南海东沙群岛以北海底沙波稳定性分析［J］.热带海洋学报，2006，25（3）：21-27.

［32］吴建政，胡日军，朱龙海，等.南海北部海底沙波研究［J］.中国海洋大学学报，2006，36（6）:1019-1023.

［33］郭晓东，邢俊兵.海南省东方县戈枕金矿带构造控矿特征探讨［J］.黄金地质，1997，3（2）：42-46.

［34］Bird P. An updated digital model of plate boundaries［J］. Geochem Geophys Geosyst, 2003, 4 （3）: 1027-1029.

［35］Moore J C, Brown K M, Horath F, et al. Plumbing accretionary prisms［M］// Tarney J, Pickering K T, Knipe R J, et al. The Behavior and Influence of Fluids in Subduction Zones. London: The Royal Society, 1991: 49-62.

［36］Moore J C, Vrolijk P. Fluids in accretionary prisms［J］. Reviews of Geophysics, 1992, 30: 113-135.

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