西北冰洋北风海盆的碎屑流沉积

doi:10.3969/j.issn.1001-909X.2023.02.001

摘要/Abstract

摘要：

极地区域大陆边缘广泛发育水下碎屑流沉积,其中很多是冰川成因,是冰盖到达陆架边缘的产物。位于北冰洋楚科奇陆缘的北风海盆,其西侧陆缘已识别出大量碎屑流事件,而对北风海盆内部碎屑流的研究却几乎没有开展。该文利用高分辨率的浅地层剖面数据,勾勒出了北风海盆上部地层的碎屑流平面展布,且进行了期次划分;并结合周边的大型冰川线理(MSGL)的分布及走向,对所有识别出的碎屑流进行了成因推断。结果表明研究区内的碎屑流主要分布在西部次海盆的西南斜坡和中北部斜坡、东部次海盆的东南部以及部分海山/陡崖之下,其来源包括周边陆架、海脊高地和盆内海山。绝大多数碎屑流与MSGL伴生存在,推测为冰川成因,其中以西南斜坡最为发育,发现了超过9期的冰川碎屑流事件,代表了在其西南的冰蚀槽(宽水深槽)内曾发生超过9次的冰流事件,这一数据远大于前人所推测的冰流事件次数(3~5次)。同时也发现部分碎屑流邻近的海山/高地上不发育MSGL等冰川触地地貌,推测其为非冰川成因,邻近区域的冰盖/冰架触地或构造活动所引发的震动可能是这类碎屑流的触发因素。

关键词: 北风海盆, 楚科奇边缘地, 冰川碎屑流, 大型冰川线理

Abstract:

Subaqueous debris flows are widely developed on polar continental margins, many of which are glacigenic, representing the products of ice sheets reaching the shelf edge. In the western Arctic Ocean, a large number of debris flows have been identified at the continental margin west of the Northwind Basin, however research on debris flows within this basin has hardly been carried out. In this study, the distribution of debris flows was outlined and their formation ages were determined using the high-resolution sub-bottom profiler data. Then the mega-scale glacial lineations (MSGL) was used as the judgment indicators to infer the origin of these debris flows. It is found that the debris flows in the study area are mainly distributed on the southwestern and northern-central slope of the western sub-basin, in the southeastern part of the eastern sub-basin, and on the slopes of some seamounts and cliffs. They are from the surrounding continental shelf, ridges and seamounts. Most debris flows coexist with MSGL and are presumed to be glacigenic. More than 9 glacigenic debris flows have been found on the southwestern slope, which may indicate more than 9 ice streams advances through the Broad Bathymetric Trough. The number of ice streams advances are much more than the previous speculation (3-5). There are also some debris flows with no ice-grounding landforms (e.g. MSGL) have been found in the nearby seamounts and are presumed to be non-glacigenic. The shock caused by the grounding of the ice sheets/shelves in the nearby area or tectonic movement may be the trigger factors for this kind of debris flows.

Key words: Northwind Basin, Chukchi Borderland, glacigenic debris flows, MSGL

中图分类号:

P512.4

徐逸鑫, 沈中延, 杨春国, 张涛. 西北冰洋北风海盆的碎屑流沉积[J]. 海洋学研究, 2023, 41(2): 1-13.

XU Yixin, SHEN Zhongyan, YANG Chunguo, ZHANG Tao. Debris flows deposition in the Northwind Basin, western Arctic Ocean[J]. Journal of Marine Sciences, 2023, 41(2): 1-13.

图/表 6

图1 北风海盆区域地理位置 (图a为白令地区北部陆缘地形、冰盖和冰蚀槽发育情况;采用的地形资料来自全球水深数据(the general bathymetric chart of the oceans, GEBCO)[22];红色方框表示图b的范围;蓝色阴影表示主要冰蚀槽,白色虚线表示东西伯利亚-楚科奇冰盖范围[15];黄色箭头表示劳伦泰德冰盖来源的冰川流动方向;黑色箭头表示东西伯利亚-楚科奇冰盖来源的冰川流动方向;缩略图中红色扇形框表示图a所示范围。图b显示了研究区北风海盆(白边红色虚线框)及邻区的水深特征和地球物理资料分布;测深资料来自北冰洋国际水深图(international bathymetric chart of the Arctic Ocean, IBCAO 4.0)[23]。图b中实线代表浅剖测线(MGL1112航次测线同时进行了浅剖和多道地震测量),其中,红色粗线代表中国第11次北极科考航次(ARC11);黑色粗线代表MGL1112航次;黑色细线代表HLY系列航次和ARK-XXIII-3航次;黄色粗线代表下文展示的部分浅剖测线;绿色粗线代表下文展示的MGL1112航次部分反射地震测线。图b中黑色阴影代表本文识别出的碎屑流在各时代综合的最大分布范围。)

Fig.1 The geographic map of the location of the Northwind Basin (Fig.a shows the topography, ice sheet and glacial trough extents in the northern continental margin of Beringia. Bathymetric data are from GEBCO[22]. Red rectangle: the range of fig.b; Blue shaded areas: glacial trough; White dashed line: suggested maximum extent of East Siberian-Chukchi Ice Sheet. Yellow arrows: ice flows from Laurentide Ice Sheet; Black arrows: ice flows from East Siberian-Chukchi Ice Sheet; Red sector in thumbnail: the range of fig.a. Fig.b shows the bathymetric characteristics of the survey area (Northwind Basin, red dotted rectangle with white edge) and its adjacent regions with distribution of geophysical lines. Bathymetric data are from IBCAO 4.0[23]. Solid line: sub-bottom profiling (SBP) data used in this study; Red thick line: China’s 11th Arctic expedition (ARC11); Black thick line: MGL1112, that at the same time with multi-channel seismic (MCS) survey; Black thin line: HLY cruises and ARK-XXIII-3; Yellow thick line: SBP sections shown in this article; Green thick line: MGL1112 MCS survey profiles shown in this article; Black shaded areas: maximum extent of debris flows (regardless of their different ages) identified in this study.)

图2 西部次海盆西南斜坡上的碎屑流 (图a为浅剖、地震测线分布及碎屑流范围,其中的红色箭头表示推测的沉积物运移方向(下同)。图b为MGL1112-MCS-09C反射地震剖面数据,地层解释据LEHMANN et al[15]的地震图像清绘而成,并参考了其对于冰川期沉积的解释,图中黑粗线表示冰川期沉积,灰细线表示前冰川期沉积。图c为ARC11-2-1部分浅剖数据,因其探测深度较其他航次深,因此选择它与相邻的MGL1112航次反射地震剖面进行对比,其中CC'剖面中浅剖探测到的最深反射面对应图b中AA'剖面的冰川期沉积底界,地层单元中红色字体表示碎屑流,蓝色字体表示正常地层(下同)。图d为 ARC11-2-2部分浅剖数据。图e为MGL1112_MCS03_2部分浅剖数据。)

Fig.2 Debris flows in the southwestern slope of the western sub-basin (Fig.a shows the distribution of SBP, MCS data and debris flows. Red arrow: inferred sediment transportation direction. Fig.b shows the MCS profile of MGL1112-MCS-09C. Stratigraphic interpretation, especially the bottom of the glacial strata is based on LEHMANN et al[15]. Black thick line: glacial strata; Gray thin line: preglacial strata. Fig.c shows the part of SBP profile of ARC11-2-1. The lowermost reflector in section CC' corresponds to the bottom of glacial strata in section AA' in fig.b. In stratigraphic units, red fonts indicate debris flows, and blue fonts indicate general strata. Fig.d shows the part of SBP profile of ARC11-2-2. Fig.e shows the part of SBP profile of MGL1112_MCS03_2.)

图3 西部次海盆中北部斜坡上的碎屑流 (图a为浅剖、地震测线分布及碎屑流范围,其中的白色虚线表示U6碎屑流范围。图b为MGL1112-MCS-07B反射地震剖面数据,地层解释据LEHMANN et al[15]的地震图像清绘而成,并参考了其对于冰川期沉积的解释,图中黑粗线表示冰川期沉积,灰细线表示前冰川期沉积。图c为MGL1112-SBP-07_2部分浅剖数据,其中BB'剖面与图b中的AA'剖面对应。图d为MGL1112-SBP-03_1部分浅剖数据。图e为HLY0905_256_0906_LF_153部分浅剖数据。)

Fig.3 Debris flows in the northern-central slope of the western sub-basin (Fig.a shows the distribution of SBP, MCS data and debris flows. White dotted line: the debris flows of U6. Fig.b shows MCS profile of MGL1112-MCS-07B. Stratigraphic interpretation, especially the bottom of the glacial strata is based on LEHMANN er al[15]. Black thick line: glacial strata; Gray thin line: preglacial strata. Fig.c shows the part of SBP profile of MGL1112-SBP-07_2. Section BB' correspond to section AA' in the zoom in fig.b. Fig.d shows the part of SBP profile of MGL1112-SBP-03_1. Fig.e shows the part of SBP profile of HLY0905_256_0906_LF_153.)

图4 东部次海盆东南端的碎屑流 (图a为浅剖测线分布及碎屑流范围。图b为MGL1112-SBP-10_3部分浅剖数据。图c为MGL1112-SBP-04_1部分浅剖数据。图d为ARC11_1_5部分浅剖数据。)

Fig.4 Debris flows in the southeastern part of eastern sub-basin (Fig.a shows the distribution of SBP data and debris flows. Fig.b shows the part of SBP profile of MGL1112-SBP-10_3. Fig.c shows the part of SBP profile of MGL1112-SBP-04_1. Fig.d shows the part of SBP profile of ARC11_1_5.)

图5 海山、陡崖周缘的碎屑流 (图a为浅剖测线分布及碎屑流范围。图b为MGL1112_MCS03_2部分浅剖数据。图c为HLY0805_229_0456_LF_066部分浅剖数据。图d为MGL1112-SBP-04_2部分浅剖数据。图e为MGL1112-SBP-08_2与MGL1112-SBP-04_2部分浅剖数据合并结果。图f为MGL1112_MCS09_1部分浅剖数据。图g为ARC11_1_4部分浅剖数据。图h为MGL1112_MCS010_2部分浅剖数据。)

Fig.5 Debris flows around seamounts and cliffs (Fig.a shows the distribution of SBP data and debris flows. Fig.b shows the part of SBP profile of MGL1112_MCS03_2. Fig.c shows the part of SBP profile of HLY0805_229_0456_LF_066. Fig.d shows the part of SBP profile of MGL1112-SBP-04_2. Fig.e shows the part of SBP profiles of MGL1112-SBP-08_2 and MGL1112-SBP-04_2. Fig.f shows the part of SBP profile of MGL1112_MCS09_1. Fig.g shows the part of SBP profile of ARC11_1_4. Fig.h shows the part of SBP profile of MGL1112_MCS010_2.)

图6 研究区的不同地貌分布 (图a为区域内MSGL(红色双向箭头)与冲沟(绿线)分布,数据大部分来自DOVE et al[11],JAKOBSSON et al[12,14],POLYAK et al[6,10],SHEN et al[20],KIM et al[9]等文献,小部分根据浅剖和多波束资料重新解释;图中黑色、白色和灰色阴影分别表示冰川碎屑流、非冰川碎屑流和难以推测成因的碎屑流。图b为HLY0805_229_0409_LF_061部分浅剖数据。图c为MGL1112-SBP-04_2部分浅剖数据。图d为HLY0703_2007_1249_LF_127部分浅剖数据。图e为 HLY1202_267_0653_LF_310部分浅剖数据。)

Fig.6 Distribution map of various landforms in study area (Fig.a shows the distribution of MSGL (red bidirectional arrow) and gullies (green line). Most of them come from DOVE et al[11], JAKOBSSON et al[12,14], POLYAK et al[6,10], SHEN et al[20], KIM et al[9]. A small part is reinterpreted based on SBP and multi-beam data. Black areas: glacigenic debris flows; White areas: non-glacigenic debris flows; Grey areas: uncertain debris flows. Fig.b shows part of SBP profile of HLY0805_229_0409_LF_061. Fig.c shows part of SBP profile of MGL1112-SBP-04_2. Fig.d shows part of SBP profile of HLY0703_2007_1249_LF_127. Fig.e shows part of SBP profile of HLY1202_267_0653_LF_310.)

参考文献 37

[1]	鲜本忠, 安思奇, 施文华. 水下碎屑流沉积:深水沉积研究热点与进展[J]. 地质论评, 2014, 60(1):39-51.
	XIAN B Z, AN S Q, SHI W H. Subaqueous debris flow: Hotspots and advances of deep-water sedimention[J]. Geological Review, 2014, 60(1): 39-51.
[2]	SULTAN N, COCHONAT P, CANALS M, et al. Triggering mechanisms of slope instability processes and sediment failures on continental margins: A geotechnical approach[J]. Marine Geology, 2004, 213(1-4): 291-321. DOI URL
[3]	VORREN T O, LEBESBYE E, ANDREASSEN K, et al. Glacigenic sediments on a passive continental margin as exemplified by the Barents Sea[J]. Marine Geology, 1989, 85(2-4): 251-272. DOI URL
[4]	VOGT P R, CRANE K, SUNDVOR E. Glacigenic mudflows on the Bear Island submarine fan[J]. Eos, Transactions American Geophysical Union, 1993, 74(40): 449-453.
[5]	LABERG J S, VORREN T O. Late Weichselian submarine debris flow deposits on the Bear Island Trough Mouth Fan[J]. Marine Geology, 1995, 127(1-4): 45-72. DOI URL
[6]	POLYAK L, EDWARDS M H, COAKLEY B J, et al. Ice shelves in the Pleistocene Arctic Ocean inferred from glaciogenic deep-sea bedforms[J]. Nature, 2001, 410(6827): 453-457. DOI URL
[7]	NIESSEN F, HONG J K, HEGEWALD A, et al. Repeated Pleistocene glaciation of the East Siberian continental margin[J]. Nature Geoscience, 2013, 6(10): 842-846. DOI
[8]	JOE Y J, POLYAK L, SCHRECK M, et al. Late Quaternary depositional and glacial history of the Arliss Plateau off the East Siberian margin in the western Arctic Ocean[J]. Quaternary Science Reviews, 2020, 228: 106099. DOI URL
[9]	KIM S, POLYAK L, JOE Y J, et al. Seismostratigraphic and geomorphic evidence for the glacial history of the northwestern Chukchi margin, Arctic Ocean[J]. Journal of Geophysical Research: Earth Surface, 2021, 126(4): e2020JF006030.
[10]	POLYAK L, DARBY D A, BISCHOF J F, et al. Stratigraphic constraints on late Pleistocene glacial erosion and deglaciation of the Chukchi margin, Arctic Ocean[J]. Quaternary Research, 2007, 67(2): 234-245. DOI URL
[11]	DOVE D, POLYAK L, COAKLEY B. Widespread, multi-source glacial erosion on the Chukchi margin, Arctic Ocean[J]. Quaternary Science Reviews, 2014, 92: 112-122. DOI URL
[12]	JAKOBSSON M, ANDREASSEN K, BJARNADÓTTIR L R, et al. Arctic Ocean glacial history[J]. Quaternary Science Reviews, 2014, 92: 40-67. DOI URL
[13]	JAKOBSSON M, GARDNER J V, VOGT P R, et al. Multibeam bathymetric and sediment profiler evidence for ice grounding on the Chukchi Borderland, Arctic Ocean[J]. Quaternary Research, 2005, 63(2): 150-160. DOI URL
[14]	JAKOBSSON M, POLYAK L, EDWARDS M, et al. Glacial geomorphology of the central Arctic Ocean: The Chukchi borderland and the Lomonosov Ridge[J]. Earth Surface Processes and Landforms, 2008, 33(4): 526-545. DOI URL
[15]	LEHMANN C, JOKAT W. Seismic constraints for ice sheets along the northern margin of Beringia[J]. Global and Planetary Change, 2022, 215: 103885. DOI URL
[16]	TAYLOR J, DOWDESWELL J A, KENYON N H, et al. Late Quaternary architecture of trough-mouth fans: Debris flows and suspended sediments on the Norwegian margin[J]. Geological Society, London, Special Publications, 2002, 203(1): 55-71. DOI URL
[17]	MOSHER D C, BOGGILD K. Impact of bottom currents on deep water sedimentary processes of Canada Basin, Arctic Ocean[J]. Earth and Planetary Science Letters, 2021, 569: 117067. DOI URL
[18]	YE L M, ZHANG W Y, WANG R, et al. Ice events along the East Siberian continental margin during the last two glaciations: Evidence from clay minerals[J]. Marine Geology, 2020, 428: 106289. DOI URL
[19]	JAKOBSSON M, NILSSON J, O’REGAN M, et al. An Arctic Ocean ice shelf during MIS 6 constrained by new geophysical and geological data[J]. Quaternary Science Reviews, 2010, 29(25/26): 3505-3517. DOI URL
[20]	SHEN Z Y, ZHANG T, GAO J Y, et al. Glacial bedforms in the Northwind Abyssal Plain, Chukchi borderland[J]. Acta Oceanologica Sinica, 2021, 40(5): 114-119.
[21]	LEHMANN C, JOKAT W, COAKLEY B. Glacial sediments on the outer Chukchi Shelf and Chukchi Borderland in seismic reflection data[J]. Marine Geophysical Research, 2022, 43(3): 1-16. DOI
[22]	MAYER L, JAKOBSSON M, ALLEN G, et al. The Nippon foundation—GEBCO seabed 2030 project: The quest to see the world’s oceans completely mapped by 2030[J]. Geosciences, 2018, 8(2): 63. DOI URL
[23]	MARTIN J, MAYER L A, CAROLINE B, et al. The international bathymetric chart of the Arctic Ocean version 4.0[J]. Scientific Data, 2020, 7(1): 176. DOI PMID
[24]	COAKLEY B, ILHAN I. Chukchi Edges Project-Geophysical constraints on the history of the Amerasia Basin[C]// American Geophysical Union, Fall Meeting Abstract, 2011: T33A-2365.
[25]	MAYER L A, ARMSTRONG A, CALDER B, et al. Sea floor mapping in the Arctic: Support for a potential US extended continental shelf[J]. The International Hydrographic Review, 2010, 3: 14-23.
[26]	MAYER L A, ARMSTRONG A. US Law of the sea cruise to map the foot of the slope and 2500-m isobath of the US Arctic Ocean margin[R]. Center for Coastal and Ocean Mapping, 2011.
[27]	EDWARDS B D, CHILDS J R, TRIEZENBERG P J, et al. 2010 Joint United States-Canadian Program to explore the limits of the extended continental shelf aboard US Coast Guard Cutter Healy—Cruise HLY1002[R]//US Geological Survey Open-File Report, 2013.
[28]	MAYER L A, ARMSTRONG A. US Law of the sea cruise to map and sample the US Arctic Ocean margin[R]. Center for Coastal and Ocean Mapping, 2012.
[29]	Multibeam report for HLY1603[R/OL]. [2022-05-02]. https://www.ngdc.noaa.gov/ships/healy/HLY1603_mb.html.
[30]	JOKAT W. The expedition of the research vessel "Polarstern" to the Arctic in 2008 (ARK-XXIII/3)[R]. Alfred Wegener Institute for Polar and Marine Research, 2009.
[31]	WESSEL P, SMITH W H F, SCHARROO R, et al. Generic mapping tools: Improved version released[J]. Eos, Transactions American Geophysical Union, 2013, 94(45): 409-410.
[32]	COFAIGH C Ó, TAYLOR J, DOWDESWELL J A, et al. Palaeo-ice streams, trough mouth fans and high-latitude continental slope sedimentation[J]. Boreas, 2003, 32(1): 37-55. DOI URL
[33]	COFAIGH C Ó, HOGAN K A, JENNINGS A E, et al. The role of meltwater in high-latitude trough-mouth fan development: The Disko Trough-Mouth Fan, West Greenland[J]. Marine Geology, 2018, 402: 17-32. DOI URL
[34]	DAMUTH J E. Echo character of the Norwegian—Greenland Sea: Relationship to quaternary sedimentation[J]. Marine Geology, 1978, 28(1/2): 1-36. DOI URL
[35]	DIPRE G R, POLYAK L, KUZNETSOV A B, et al. Plio-Pleistocene sedimentary record from the Northwind Ridge: New insights into paleoclimatic evolution of the western Arctic Ocean for the last 5 Ma[J]. Arktos, 2018, 4(1): 1-23.
[36]	SIEGERT M J, DOWDESWELL J A. Topographic control on the dynamics of the Svalbard-Barents Sea ice sheet[J]. Global and Planetary Change, 1996, 12(1-4): 27-39. DOI URL
[37]	WINSBORROW M C M, CLARK C D, STOKES C R. What controls the location of ice streams?[J]. Earth-Science Reviews, 2010, 103(1/2): 45-59. DOI URL