南海东北部陆坡天然气水合物藏特征
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摘要
2013年下半年,国土资源部中国地质调查局、广州海洋地质调查局在南海东北部陆坡水深664~1 420m范围内钻探13个站位,取心获取了大量、多种类型的天然气水合物(以下简称水合物)实物样品,其中甲烷气体含量超过99%。对南海东北部陆坡天然气水合物成藏特征的研究结果表明:1地震反射剖面上具有多道似海底反射层(BSR)、振幅空白带(BZ)、BSR与地层斜交、速度反转等地震异常;2测井曲线揭示含水合物沉积层具有高电阻率(200Ω·m)、高纵波速度(2 700m/s)的特征;3地震和测井异常特征暗示该区具有单、双层水合物藏组合特征;4该区域水合物藏位于海底之下埋深220m以内的粉砂质黏土及生物碎屑灰岩沉积物中,水合物饱和度为45%~100%;5自然状态下,水合物呈块状、层状、瘤状、脉状、分散状等5种赋存形式;6研究区天然气水合物赋存类型多、饱和度高、甲烷纯度高,初步估算该区天然气水合物地质储量约为1 250×108 m3(50%概率条件下),是有利的勘探目标区。
From sample cores obtained in exploration drilling at 13sites(664–1 420mdeep)on the northeastern slope of the South China Sea,we found a large amount of gas hydrates of multiple types,the methane gas content of which is more than 99%.After an integrated analysis of their characteristics,the following findings were obtained.(1)From the multichannel seismic profile,we detected many significant seismic anomalies,including Bottom Simulating Reflection(BSR)and Blanking Zone(BZ),BSR oblique crossing the formation,velocity inversion.(2)The borehole logging data also revealed the characteristics of high electrical resistivity(up to 200m·Ω)and high acoustic velocities(up to 2 700m/s)of the hydrate-bearing sediments.(3)Seismic and logging anomalies implied that both single-layer and double-layer gas hydrates occurred in the northeastern slope of the South China Sea.(4)The gas hydrate resources of this area are preserved in the sediments like silty clays or limestone grains within the depth of 220 meters below the seafloor(mbsf),where the saturations of gas hydrates range from 45%to 100%.(5)In a natural state,gas hydrates were deposited primarily in the form of massive blocks,thin beds,veins,nodular or disperse particles,among which the first four types were generally formed in the silty clay with coarser grain sizes or in the weak belts near the seafloor with many tracks of the neotectonics.In conclusion,this drilling area was considered to be a promising exploration target of natural gas hydrate resources with about 125 billion m3 because of its favorable features such as a variety of occurrence types,high porous saturation,and high methane concentration.
From sample cores obtained in exploration drilling at 13sites(664–1 420mdeep)on the northeastern slope of the South China Sea,we found a large amount of gas hydrates of multiple types,the methane gas content of which is more than 99%.After an integrated analysis of their characteristics,the following findings were obtained.(1)From the multichannel seismic profile,we detected many significant seismic anomalies,including Bottom Simulating Reflection(BSR)and Blanking Zone(BZ),BSR oblique crossing the formation,velocity inversion.(2)The borehole logging data also revealed the characteristics of high electrical resistivity(up to 200m·Ω)and high acoustic velocities(up to 2 700m/s)of the hydrate-bearing sediments.(3)Seismic and logging anomalies implied that both single-layer and double-layer gas hydrates occurred in the northeastern slope of the South China Sea.(4)The gas hydrate resources of this area are preserved in the sediments like silty clays or limestone grains within the depth of 220 meters below the seafloor(mbsf),where the saturations of gas hydrates range from 45%to 100%.(5)In a natural state,gas hydrates were deposited primarily in the form of massive blocks,thin beds,veins,nodular or disperse particles,among which the first four types were generally formed in the silty clay with coarser grain sizes or in the weak belts near the seafloor with many tracks of the neotectonics.In conclusion,this drilling area was considered to be a promising exploration target of natural gas hydrate resources with about 125 billion m3 because of its favorable features such as a variety of occurrence types,high porous saturation,and high methane concentration.
引文
[1]张光学,黄永样,祝有海,等.南海天然气水合物的成矿远景[J].海洋地质与第四纪地质,2002,22(1):75-81.ZHANG Guangxue,HUANG Yongyang,ZHU Youhai,et al.Prospect of gas hydrate resources in the South China Sea[J].Marine Geology&Quaternary Geology,2002,22(1):75-81.
[2]黄永样,张光学.我国海域天然气水合物地质—地球物理特征及前景[M].北京:地质出版社,2009.HUANG Yongyang,ZHANG Guangxue.Geologicalgeophsical characteristics and prospects of gas hydrate in China Marine[M].Beijing:Geological Publishing House,2009.
[3]吴必豪,张光学,祝有海,等.中国近海天然气水合物的研究进展[J].地学前缘,2003,10(1):177-189.WU Bihao,ZHANG Guangxue,ZHU Youhai,et al.Progress of gas hydrate investigation in China offshore[J].Earth Science Frontiers,2003,10(1):177-189.
[4]LIU C S,SCHNURLE P,WANG Yunshuen,et al.Distribution and characters of gas hydrate offshore of southwestern Taiwan[J].Terrestrial Atmospheric and Oceanic Sciences,2006,17(4):615-644.
[5]FUH S C,CHERN C C,LIANG S C,et al.The biogenic gas potential of the submarine canyon systems of Plio-Peistocene Foreland Basin,southwestern Taiwan[J].Marine and Petroleum Geology,2009,26(7):1087-1099.
[6]陆红锋,孙晓明,张美.南海天然气水合物沉积物矿物学和地球化学[M].北京:科学出版社,2011.LU Hongfeng,SUN Xiaoming,ZHANG Mei.Sediment mineralogy and geochemistry of gas hydrate in the South China Sea[M].Beijing:Science Press,2011.
[7]徐华宁,梁蓓雯,张光学,等.南海北部陆坡天然气水合物地震识别研究[J].天然气工业,2006,26(9):49-51.XU Huaning,LIANG Beiwen,ZHANG Guangxue,et al.Seismic identification of gas hydrate on northern slope of South China Sea[J].Natural Gas Industry,2006,26(9):49-51.
[8]吴能友,张海啟,杨胜雄,等.南海神狐海域天然气水合物成藏系统初探[J].天然气工业,2007,27(9):1-6.WU Nengyou,ZHANG Haiqi,YANG Shengxiong,et al.Preliminary discussion on natural gas hydrate(NGH)reservoir system of Shenhu area,north slope of South China Sea[J].Natural Gas Industry,2007,27(9):1-6.
[9]ZHANG Guangxue,YANG Shengxiong,ZHANG Ming,et al.GMGS2expedition investigates rich and complex gas hydrate environment in the South China Sea[J].NETL,Fire in the Ice(Methane Hydrate Newsletter),2014,14(1):1-5.
[10]LIN Chechuan,LIN A Tien-Shun,LIU Char-Shine,et al.Geological controls on BSR occurrences in the incipient arc-continent collision zone off southwest Taiwan[J].Marine and Petroleum Geology,2009,26(7):1118-1131.
[11]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 Geology&Quaternary Geology,2008,28(1):99-104.
[12]易海,钟广见,马金凤.台西南盆地新生代断裂特征与盆地演化[J].石油实验地质,2007,29(6):560-564.YI Hai,ZHONG Guangjian,MA Jinfeng.Fracture characteristics and basin evolution of the Taixinan Basin in Cenozoic[J].Petroleum Geology&Experiment,2007,29(6):560-564.
[13]LI Lun,LEI Xinhua,ZHANG Xin,et al.Gas hydrate and associated free gas in the Dongsha Area of northern South China Sea[J].Marine and Petroleum Geology,2013,39(1):92-101.
[14]黄永样,Erwin Suess,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OS-177航次成果专报[M].北京:地质出版社,2008.HUANG Yongyang,SUESS E,WU Nengyou,et al.Methane and gas hydrate geology of the northern South China Sea:Sino-German Cooperative SO-177 Cruise Report[M].Beijing:Geological Publishing House,2008.
[15]沙志彬,杨木壮,梁劲.天然气水合物成矿的沉积控制因素[J].海洋地质动态,2003,19(6):16-20.SHA Zhibin,YANG Muzhuang,LIANG Jin.Sedimentation-controlling factors of natural gas hydration[J].Marine Geology Letters,2003,19(6):16-20.
[16]梁金强,王宏斌,苏新,等.南海北部陆坡天然气水合物成藏条件及其控制因素[J].天然气工业,2014,34(7):128-135.LIANG Jinjiang,WANG Hongbin,SU Xin,et al.Natural gas hydrate formation conditions and the associated controlling factors in the northern slope of the South China Sea[J].Natural Gas Industry,2014,34(7):128-135.
[17]苏丕波,沙志彬,常少英,等.珠江口盆地东部海域天然气水合物的成藏地质模式[J].天然气工业,2014,34(6):162-168.SU Pibo,SHA Zhibin,CHANG Shaoying,et al.Geological models of gas hydrate formation in the eastern sea area of the Pearl River Mouth Basin[J].Natural Gas Industry,2014,34(6):162-168.
[18]沙志彬,王宏斌,龚跃华.断层与天然气水合物的关系[M]∥南海地质研究.北京:地质出版社,2004:41-47.SHA Zhibin,WANG Hongbin,GONG Yuehua.The relations between faults and gas hydrates[M]∥Geological Research of South China Sea.Beijing:Geological Publishing House,2004:41-47.
[19]沙志彬,王宏斌,杨木壮,等.天然气水合物成矿带的识别技术研究[J].现代地质,2008,22(3):438-446.SHA Zhibin,WANG Hongbin,YANG Muzhuang,et al.Study on recognizing technology of gas hydrates zone[J].Geoscience,2008,22(3):438-446.
[20]梁劲,王明君,陆敬安,等.南海北部神狐海域含天然气水合物沉积层的速度特征[J].天然气工业,2013,33(7):29-35.LIANG Jin,WANG Mingjun,LU Jing′an,et al.Characteristics of sonic and seismic velocities of gas hydrate bearing sediments in the Shenhu area,northern South China Sea[J].Natural Gas Industry,2013,33(7):29-35.
[21]陆敬安,杨胜雄,吴能友,等.南海神狐海域天然气水合物地球物理测井评价[J].现代地质,2008,22(3):447-451.LU Jing′an,YANG Shengxiong,WU Nengyou,et al.Well logging evaluation of gas hydrates in Shenhu area,South China Sea[J].Geoscience,2008,22(3):447-451.
[22]COLLETT T S,LEWIS R E,WINTERS W J,et al.Downhole well log and core montages from the Mount Elbert Gas Hydrate Stratigraphic Test Well,Alaska North Slope[J].Marine and Petroleum Geology,2011,28(2):561-577.
[23]梁金强,吴能友,杨木壮,等.天然气水合物资源量估算方法及应用[J].地质通报,2006,25(9):1205-1210.LIANG Jinqiang,WU Nengyou,YANG Muzhuang,et al.Resource estimate method of gas hydrates and its application[J].Geological Bulletin of China,2006,25(9):1205-1210.
[24]王秀娟,吴时国,刘学伟,等.东沙海域天然气水合物特征分析及饱和度估算[J].石油物探,2009,48(5):445-452.WANG Xiujuan,WU Shiguo,LIU Xuewei,et al.Characteristic analysis and saturation estimation of gas hydrate in Dongsha sea area[J].Geophysical Prospecting for Petroleum,2009,48(5):445-452.
[2]黄永样,张光学.我国海域天然气水合物地质—地球物理特征及前景[M].北京:地质出版社,2009.HUANG Yongyang,ZHANG Guangxue.Geologicalgeophsical characteristics and prospects of gas hydrate in China Marine[M].Beijing:Geological Publishing House,2009.
[3]吴必豪,张光学,祝有海,等.中国近海天然气水合物的研究进展[J].地学前缘,2003,10(1):177-189.WU Bihao,ZHANG Guangxue,ZHU Youhai,et al.Progress of gas hydrate investigation in China offshore[J].Earth Science Frontiers,2003,10(1):177-189.
[4]LIU C S,SCHNURLE P,WANG Yunshuen,et al.Distribution and characters of gas hydrate offshore of southwestern Taiwan[J].Terrestrial Atmospheric and Oceanic Sciences,2006,17(4):615-644.
[5]FUH S C,CHERN C C,LIANG S C,et al.The biogenic gas potential of the submarine canyon systems of Plio-Peistocene Foreland Basin,southwestern Taiwan[J].Marine and Petroleum Geology,2009,26(7):1087-1099.
[6]陆红锋,孙晓明,张美.南海天然气水合物沉积物矿物学和地球化学[M].北京:科学出版社,2011.LU Hongfeng,SUN Xiaoming,ZHANG Mei.Sediment mineralogy and geochemistry of gas hydrate in the South China Sea[M].Beijing:Science Press,2011.
[7]徐华宁,梁蓓雯,张光学,等.南海北部陆坡天然气水合物地震识别研究[J].天然气工业,2006,26(9):49-51.XU Huaning,LIANG Beiwen,ZHANG Guangxue,et al.Seismic identification of gas hydrate on northern slope of South China Sea[J].Natural Gas Industry,2006,26(9):49-51.
[8]吴能友,张海啟,杨胜雄,等.南海神狐海域天然气水合物成藏系统初探[J].天然气工业,2007,27(9):1-6.WU Nengyou,ZHANG Haiqi,YANG Shengxiong,et al.Preliminary discussion on natural gas hydrate(NGH)reservoir system of Shenhu area,north slope of South China Sea[J].Natural Gas Industry,2007,27(9):1-6.
[9]ZHANG Guangxue,YANG Shengxiong,ZHANG Ming,et al.GMGS2expedition investigates rich and complex gas hydrate environment in the South China Sea[J].NETL,Fire in the Ice(Methane Hydrate Newsletter),2014,14(1):1-5.
[10]LIN Chechuan,LIN A Tien-Shun,LIU Char-Shine,et al.Geological controls on BSR occurrences in the incipient arc-continent collision zone off southwest Taiwan[J].Marine and Petroleum Geology,2009,26(7):1118-1131.
[11]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 Geology&Quaternary Geology,2008,28(1):99-104.
[12]易海,钟广见,马金凤.台西南盆地新生代断裂特征与盆地演化[J].石油实验地质,2007,29(6):560-564.YI Hai,ZHONG Guangjian,MA Jinfeng.Fracture characteristics and basin evolution of the Taixinan Basin in Cenozoic[J].Petroleum Geology&Experiment,2007,29(6):560-564.
[13]LI Lun,LEI Xinhua,ZHANG Xin,et al.Gas hydrate and associated free gas in the Dongsha Area of northern South China Sea[J].Marine and Petroleum Geology,2013,39(1):92-101.
[14]黄永样,Erwin Suess,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OS-177航次成果专报[M].北京:地质出版社,2008.HUANG Yongyang,SUESS E,WU Nengyou,et al.Methane and gas hydrate geology of the northern South China Sea:Sino-German Cooperative SO-177 Cruise Report[M].Beijing:Geological Publishing House,2008.
[15]沙志彬,杨木壮,梁劲.天然气水合物成矿的沉积控制因素[J].海洋地质动态,2003,19(6):16-20.SHA Zhibin,YANG Muzhuang,LIANG Jin.Sedimentation-controlling factors of natural gas hydration[J].Marine Geology Letters,2003,19(6):16-20.
[16]梁金强,王宏斌,苏新,等.南海北部陆坡天然气水合物成藏条件及其控制因素[J].天然气工业,2014,34(7):128-135.LIANG Jinjiang,WANG Hongbin,SU Xin,et al.Natural gas hydrate formation conditions and the associated controlling factors in the northern slope of the South China Sea[J].Natural Gas Industry,2014,34(7):128-135.
[17]苏丕波,沙志彬,常少英,等.珠江口盆地东部海域天然气水合物的成藏地质模式[J].天然气工业,2014,34(6):162-168.SU Pibo,SHA Zhibin,CHANG Shaoying,et al.Geological models of gas hydrate formation in the eastern sea area of the Pearl River Mouth Basin[J].Natural Gas Industry,2014,34(6):162-168.
[18]沙志彬,王宏斌,龚跃华.断层与天然气水合物的关系[M]∥南海地质研究.北京:地质出版社,2004:41-47.SHA Zhibin,WANG Hongbin,GONG Yuehua.The relations between faults and gas hydrates[M]∥Geological Research of South China Sea.Beijing:Geological Publishing House,2004:41-47.
[19]沙志彬,王宏斌,杨木壮,等.天然气水合物成矿带的识别技术研究[J].现代地质,2008,22(3):438-446.SHA Zhibin,WANG Hongbin,YANG Muzhuang,et al.Study on recognizing technology of gas hydrates zone[J].Geoscience,2008,22(3):438-446.
[20]梁劲,王明君,陆敬安,等.南海北部神狐海域含天然气水合物沉积层的速度特征[J].天然气工业,2013,33(7):29-35.LIANG Jin,WANG Mingjun,LU Jing′an,et al.Characteristics of sonic and seismic velocities of gas hydrate bearing sediments in the Shenhu area,northern South China Sea[J].Natural Gas Industry,2013,33(7):29-35.
[21]陆敬安,杨胜雄,吴能友,等.南海神狐海域天然气水合物地球物理测井评价[J].现代地质,2008,22(3):447-451.LU Jing′an,YANG Shengxiong,WU Nengyou,et al.Well logging evaluation of gas hydrates in Shenhu area,South China Sea[J].Geoscience,2008,22(3):447-451.
[22]COLLETT T S,LEWIS R E,WINTERS W J,et al.Downhole well log and core montages from the Mount Elbert Gas Hydrate Stratigraphic Test Well,Alaska North Slope[J].Marine and Petroleum Geology,2011,28(2):561-577.
[23]梁金强,吴能友,杨木壮,等.天然气水合物资源量估算方法及应用[J].地质通报,2006,25(9):1205-1210.LIANG Jinqiang,WU Nengyou,YANG Muzhuang,et al.Resource estimate method of gas hydrates and its application[J].Geological Bulletin of China,2006,25(9):1205-1210.
[24]王秀娟,吴时国,刘学伟,等.东沙海域天然气水合物特征分析及饱和度估算[J].石油物探,2009,48(5):445-452.WANG Xiujuan,WU Shiguo,LIU Xuewei,et al.Characteristic analysis and saturation estimation of gas hydrate in Dongsha sea area[J].Geophysical Prospecting for Petroleum,2009,48(5):445-452.
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