得益于多波束测深系统对海底精细地形特征的展现能力,2011年在长山群岛南侧进行的多波束水深调查中一种特殊的环状微洼地地貌引起了调查人员的注意,该地貌形态与以往报道的海底侵蚀坑槽和洼地有很大的不同,且成群密集分布。本文依据多波束调查数据对环状微洼地的具体形态和地貌特征进行了详细描述,将环状微洼地分为3种不同的类型,并利用地形地貌分析手段,结合收集的地质环境资料对该地貌的成因进行探讨,认为该地貌形态应与海底浅层气体或油气泄漏有关,且后期受到水动力的改造。
Abstract
Benefit from the ability of displaying fine topography features of multi-beam sounding system, a special seabed landform drew much attention of the researchers during the investigation at the north Yellow Sea. This seabed landform was a kind of micro ring depression quite different from the submarine depressions reported previously. It developed at the plain seafloor in the water depth of 55 m to the south of the Changshan Archipelago, circular or irregular ellipse shape, with shallow grooves along the edge, protrusion or depression in the central. Each depression has different size, most of which has a major axis of about 2 km, with the shallow groove along the edge of 200~300 m wide and 0.25~2 m depth. Several micro depressions arranged in a row, with the regional trend of NW—SE or NE—SW.
The topography form and features of the micro ring depressions were described in detail in this paper based on the multi-beam survey data. They were divided it into three types with different distributions and morphologies. TypeⅠdistributed at the northeast of the area, circular or elliptical in plan view, with protrusion in the central. TypeⅡdistributed at the southeast of the area, to the north of TypeⅠarea, elliptical or elongated in plain view with depression in the central. Type Ⅲ distributed at the southwest of the area, curved in plain view, and much shorter and shallower than the previous ones. Given the circular or ellipse morphology, the annular micro depression may relate to the sub-bottom gas leakage, which can produce pockmarks with circular or elliptical shape. Meanwhile, shallow gas leakage produced by sub-bottom profile records and the deposit of peat discovered in boreholes 8 km south to the study area can support this opinion.
Therefore, it is possible that the micro ring depressions were formed by sub-bottom shallow gas leakage, and be transformed by bottom current and submarine slumping. If the suggestion can be confirmed, it will be great significance to the study of environmental evolution of the northern Yellow Sea and will provide new inspiration to the oil and gas exploration in this area.
关键词
环状微洼地 /
浅层气 /
海底麻坑 /
北黄海
Key words
ring depression /
shallow gas /
pockmark /
the north Yellow Sea
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参考文献
[1] WANG Gui-zhi, GAO Shu, LI Feng-ye.Holocene mud deposits in the west of the northern Huanghai Sea[J]. Acta Oceanologica Sinica, 2003(25):125-134.
王桂芝,高抒,李凤业.北黄海西部的全新世泥质沉积[J].海洋学报,2003(25):125-134.
[2] CHENG Peng, GAO Shu. Net sediment transport patterns over the northwestern Yellow Sea, based upon grain size trend analysis[J]. Oceanlogia et Limnologia Sinica, 2000,31(6):604-615.
程鹏,高抒.北黄海西部海底沉积物的粒度特征和净输运趋势[J].海洋与湖沼,2000,31(6):604-615.
[3] WANG Wei, LI An-Chun, XU Fang-Jian, et al. Distribution of surface sediments and sedimentary environment in the north Yellow Sea[J]. Oceanologia et Limnologia Sinica, 2009,40(5):525-531.
王伟,李安春,徐方健,等.北黄海表层沉积物粒度分布特征及其沉积环境分析[J].海洋与湖沼,2009,40(5):525-531.
[4] Qin Yun-Shan, ZHAO Yi-Yang, CHEN Li-Rong, et al. East Sea geology[M]. Beijing: Ocean Press, 1989.
秦蕴珊,赵一阳,陈丽蓉,等.东海地质[M]. 北京:海洋出版社,1989.
[5] QI Jun, LI Feng-ye, SONG Jin-ming, et al. Sedimentation rate and flux of the north Yellow Sea[J]. Marine Geology and Quaternary Geology, 2004,24(2):9-14.
齐君,李凤业,宋金明,等.北黄海沉积速率及其沉积通量[J].海洋地质与第四纪地质,2004,24(2):9-14.
[6] LIU Zheng-xia, XIA Dong-xing. China offshore sands[M]. Beijing: Ocean Press, 2004.
刘振夏,夏东兴.中国近海潮流沉积沙体[M]. 北京:海洋出版社,2004.
[7] KING L H, MACLEAN B. Pockmarks on the Scotian Shelf[J]. Geological Society of America Bulletin,1970,81(10):3 141-3 148.
[8] GAY A M, LOPEZ M, BERNDT C, et al. Geological controls on focused fluid flow associated with seafloor seeps in the Lower Congo Basin[J]. Marine Geology, 2007,244(1-4): 68-92.
[9] LI Shou-jun, CHU Feng-you, FANG Yin-xia, et al.Associated interpretation of sub-bottom and single-channel seismic profiles from slope of Shenhu Area in the northern South China Sea characteristics of gas hydrate sediment[J]. Journal of Tropical Oceanography,2010,29(4): 56-62.
李守军,初凤友,方银霞,等.南海北部陆坡神狐海域浅地层与单道地震剖面联合解释——水合物区沉积地层特征[J].热带海洋学报,2010,29(4):56-62.
[10] LI Jing, ZHANG Zhi-xun, LI Yang. The analysis of the type and causes of the micro-landscape in the northern of East China Sea, The 27th annual meeting of the Chinese Geophysical Society[C]//Hefei: Press of University of Science and Technology of China,2011:930.
李晶,张志珣,李阳.东海北部陆架区微地貌类型及其成因探讨.中国地球物理学会第二十七届年会论文集[C]//合肥:中国科技大学出版社,2011:930.
[11] GU Zhao-feng, ZHANG Zhi-xun, LIU Huai-shan.Seismic features of shallow gas in the western area of the Yellow Sea[J].Marine Geology and Quaternary Geology, 2006,26(3): 65-74.
顾兆峰,张志珣,刘怀山.南黄海西部地区浅层气地震特征[J].海洋地质与第四纪地质,2006,26(3):65-74.
[12] ZHAO Tie-hu, ZHANG Xun-hua, WANG Xiu-tian,et al. Acoustic detection of seabed hydrocarbon seepage in the north depression of South Yellow Sea Basin[J]. Petroleum Exploration and Development,2009,36(2):195-199.
赵铁虎,张训华,王修田,等.南黄海盆地北部坳陷海底油气渗漏的声学探测[J].石油勘探与开发,2009,36(2):195-199.
[13] CATHLES L M, SU Zheng, CHEN Duo-fu. The physics of gas chimney and pockmark formation, with implications for assessment of seafloor hazards and gas sequestration[J].Marine and Petroleum Geology, 2010,27(1):82-91.
[14] LI Wen-yong, WANG Hou-jin, BAI Zhi-lin, et al. New progress in the study of tectonic geometry of the north Yellow Sea Basin[J]. Journal of Geomechanics,2006,12(1):12-22.
李文勇,王后金,白志琳,等.北黄海盆地构造几何学研究新进展[J].地质力学学报,2006,12(1):12-22.
[15] XUN Dong-yu, LIU Xi-qing, ZHANG Xun-hua, et al. China offshore geology[M]. Bejing: Geology Press,1997.
许东禹,刘锡清,张训华,等.中国近海地质[M]. 北京:地质出版社,1997.
[16] CHEN Xiao-hui, LI Ri-hui, XU Xiao-da. Shallow seismic records and late Pleistocene Stratigraphy of the north Yellow Sea[J]. Marine Geology and Quaternary Geology, 2011,31(3):17-22.
陈晓辉,李日辉,徐晓达.北黄海浅层声学地层[J].海洋地质与第四纪地质,2011,31(3):17-22.
[17] LIU Xin, GAO Shu. Interpreting the late Quaternary shallow seismic record of the western part of the north Yellow Sea[J]. Marine Geology and Quaternary Geology, 2005,25(3):61-68.
刘欣,高抒.北黄海西部晚第四纪浅层地震剖面层序分析[J].海洋地质与第四纪地质,2005,25(3):61-68.
基金
国土资源部海洋区域地质调查资助项目(GZH200800501);国家海洋公益性行业科研专项经费资助项目(201005005)
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