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台湾海峡西南部水螅水母的生态研究 总被引：3，自引：1，他引：3
本调查海区位于台湾海峡西南部,包括福建省南部和广东省东部的广大海域(北纬22°00'-24°00',东经116°00'-118°40').本文结合福建省闽南渔场调查的任务,着重分析了该海区各个站位的浮游水螅水母类的个体数量,试就水螅水母的平面分布,季节分布及生态特点进行探讨,为今后进一步研究台湾海峡海洋学特点及水产资源开发利用提供参考资料. 相似文献
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本文叙述了用碳同位素质谱、毛细管气相色谱和三维全扫描荧光法等现代分析方法测定的沉积物中有机质的分布特征,从有机地球化学的观点探讨了东海长江口邻近海域(30°06'—31°30'N,122°30'—124°30'E)有机沉积物的来源,结果表明,该区域沉积物中的有机质主要来自长江口陆源植物和近海洋浮游生物,且长江陆源物从河口向海迅速减少,其中大部分沉积在123°E以西附近,这与其他海洋地质学家的研究结果相符. 相似文献
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东海浮游动物生物量分布特征 总被引：24，自引：1，他引：23
根据1997～2000年东海海域23°30'～33°00'N,118°30'～128°00'E分别进行4个季节的海洋调查资料,对东海区浮游动物总生物量及饵料生物量的数量变动,时空分布及与鱼渔场关系作了分析.结果表明,四季总生物量均值为65.32mg/m3,其中秋季大于夏季大于春季大于冬季;饵料浮游动物生物量均值为40.9mg/m3,约占总生物量的60%,其中秋季大于夏季大于冬季大于春季.总生物量与饵料生物量平面分布趋势基本一致,高生物量(250～500mg/m3)区分布范围极小,一般占总调查面积的1%～4%.东海北部近海125°00'E以西,29°30'N以北水域生物量季节变化最明显.饵料浮游动物生物量平面分布取决于甲壳动物丰度的分布.饵料浮游动物生物量与鳀鱼中心渔场及其仔、稚鱼高密集区分布存在着较好的对应关系,春季鳀鱼中心渔场(>100kg/h1)和仔、稚鱼高密集区(≥100尾/网)位于东海中南部(28°00'～29°30'N)饵料浮游动物最高生物量(100～250mg/m3)密集区内或边缘水域. 相似文献
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东海中南部鱼类群聚结构的空间特征 总被引：7，自引：0，他引：7
依据1997～2000年东海中南部(25°30'～29°00'N,120°30'～127°00'E)四个季节的底拖网调查资料,运用聚类分析和非度量多维标度(NMDS)的方法分析了东海中南部鱼类群聚结构的空间特征,结果显示,东海中南部鱼类群聚大致可分为近海群聚和外海群聚.在不同季节两个群聚的种类组成保持了相对的稳定,并且具有一定的持续性.近海群聚的特征种类为带鱼、发光鲷等.外海群聚的特征种类主要为黄鳍马面鲀、短尾大眼鲷、黄鲷等.鱼类群聚与环境因子水深有较好的相关关系. 相似文献
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达山岛、平岛、车牛山岛邻近海域大型底栖生物分布特征 总被引：7，自引：0，他引：7
在海洋底栖生态系中,大型底栖生物在有机碎屑的分解利用、调节泥水界面的物质交换、促进水体的自净化中起着重要的作用,自身又是其他经济动物的食物,其生产量与渔业产量密切相关,因而底栖生物资源量分布常是衡量海区渔业资源状况的最基本要素.为了解苏、鲁交界海域的底栖生物资源量现状,于2002年6月对达山岛、平岛、车牛山岛(以下简称前三岛)邻近海域的大型底栖生物进行了调查,调查区位于海洲湾外侧,最近点距山东省岚山港和江苏省连云港约10～20km,调查范围为35°08 263'～34°59 598'N,119°14 686'～120°21 160'E. 相似文献
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A marine magnetic survey was carried out in and around the northern part of Socotra Basin, offshore Korea (31°42′32″–32°46′29″N
and 123°56′26″–125°49′16″E), in order to better delineate its northern and eastern boundaries. Analyses of the observed magnetic
field and estimation of the basement depth were used to assess these boundaries. The power spectrum and the three-dimensional
analytical signal methods were used for depth estimation and to reconstruct basement configuration. Estimated depths resulting
from the power spectrum method range from 1.5 to 6.0 km for deep sources (basement troughs), and from 0.3 to 1.7 km for shallower
sources (basement peaks). An isopach map shows that the sedimentary sequence varies from 1.4 to 6.0 km in thickness. Estimated
depths from the analytic signal method fluctuate in the range 1.2–6 km. The results of the observed field analysis and depth
estimation indicate good agreement with the formerly proposed eastern boundary but disagreement with the northern boundary.
The findings suggest either an extension of the Socotra Basin or the existence of other sub-basins possibly interconnected
with the study area. 相似文献
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Examining bathymetric and seismic reflection data collected from the deep-sea region between Taiwan and Luzon in 2006 and
2008, we identified a connection between a submarine canyon, a deep-sea channel, and an oceanic trench in the northern South
China Sea. The seafloor of the South China Sea north of 21°N is characterized by two broad slopes: the South China Sea Slope
to the west, and the Kaoping Slope to the east, intersected by the prominent Penghu Canyon. This negative relief axis parallels
the strike of the Taiwan orogen, extends downslope in an approx. N–S direction, and eventually merges with the northern Manila
Trench via a hitherto unidentified channel. The discovery of this channel is pivotal, because it allows connecting the Penghu
Canyon to the Manila Trench. This channel is 80 km long and 20–30 km wide, with water depths of 3,500–4,000 m. The progressive
morphological changes recorded in the aligned canyon, channel, and trench suggest that they represent three distinct segments
of the same longitudinal sediment conduit from southern Taiwan to the northern Manila Trench. Major sediment input would be
via the Kaoping Canyon and Kaoping Slope, with a smaller contribution from the South China Sea Slope. We determined the northern
end of the Manila Trench to be located at about 20°15′N, 120°15′E, where sediment accumulation has produced a bathymetry shallower
than 4,000 m, thereby abruptly terminating the trench morphology. Comparison with existing data reveals a similarity with,
for example, the Papua New Guinea–Solomon Sea Plate convergent zone, another modern analog of a mountain source to oceanic
sink longitudinal sediment transport system comprising canyon–channel–trench interconnections. 相似文献
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石岛地震台远震记录反演研究 总被引：7，自引：0，他引：7
利用石岛地震台的远震体波记录,采用旋转相关函数法和接收函数法分别反演了台站下方介质的各向异性特征和速度结构.(1)对震中距25°~35°且记录良好的5次地震的ScS震相,采用旋转相关函数法反演了岩石圈的剪切波分裂参数.对深源地震的反演结果表明,石岛地震台快波偏振方向为N94°E,这意味着西沙附近处于近东西向微偏南的拉张或地壳下方的地幔流方向为近东西微偏南,西沙地区地壳是过渡性的,其底部的驱动力主要来自与欧亚板块运动一致的物质流.快慢波时间延迟为1.3 s,估算各向异性层厚度为100 km左右.(2)对震中距20°~60°的9次远震P波波形三分向记录,采用接收函数法反演了地壳和上地幔的S波速度结构.反演结果表明,石岛地震台下方地壳分为3层:约5 km以上有一速度梯度带,S波速度从1.5 km/s逐渐增加到3.5 km/s,其间有若干小的分层;在5~16 km的平均速度为3.8 km/s左右,其间有若干小的分层;在16.0~26.5 km的速度为3.6 km/s左右,这是一个明显的低速层;莫霍面埋深为26.5 km,莫霍面以下平均速度为4.7 km/s,也有若干小的分层,尤其是在莫霍面之下有一个明显的低速层.根据转换波到时分析和速度剖面左右摆动现象,认为反演结果中的小分层可能是不真实的,但在16.0~26.5 km的低速层的真实程度还是较高的,表明下地壳具有一定的塑性. 相似文献
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黑潮延伸体邻近区域中尺度涡特征统计分析 总被引：7，自引：3，他引：4
本文利用20年的卫星高度计资料,对黑潮延伸体邻近海区(25°—45°N,135°E—175°W)中尺度涡的统计特征以及季节变化进行了统计研究。基于涡旋自动识别方法,共识别出本区域3006个气旋涡轨迹和2887个反气旋涡轨迹,其平均周期分别为9.99周和11.00周,平均半径分别为69.5km和71.8km。长生命周期涡旋的平均半径、涡度、涡动能(EKE)和涡旋能量密度(EI)在生命周期内大致都经历了增大-基本保持不变-减小这三个阶段。绝大多数涡旋沿纬线向西移动,经向移动距离较小,气旋涡和反气旋涡在西向传播过程中都具有明显的向南(赤道)偏离趋势。涡旋的生成数量与总数量均在春夏季达到最多,且这一时期涡旋的平均涡度、EKE、EI处于较高水平。 相似文献
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厄尔尼诺/拉尼娜信号循环回路及其传播特性研究 总被引：4，自引：0，他引：4
基于1992～2001年卫星高度计资料分析了海面高度距平在厄尔尼诺/拉尼娜(El Niño/La Niña)现象中的演变过程,发现:(1)在El Niño过程中,海面高度正距平信号从西太平洋沿赤道海域向东传播至东海岸,然后分成南北两支,北支在10°N附近从东太平洋传回西太平洋的信号最强,到达西太沿岸海域再传回赤道,表明El Niño信号传播在北半球存在一明显循环回路.赤道以南循环圈不及赤道以北环路清晰.东太平洋的季节变化信号主要通过6°N,10°N和8°S附近的3个通道向西太平洋传播.La Niña信号主要从5°N和7°S向西传播;(2)在大洋海盆尺度快速传播信号背景下,存在波长700～800km的慢速传播信号,两类信号将信息在太平洋内传送.传播速度分析表明,慢速传播信号的相速与Rossby波相速相符,而快速传播信号应该是海洋对大气变异的响应. 相似文献
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本文使用基于热成风速度的涡旋识别拓展方法,通过海表面温度数据对黑潮延伸体区域50~100 km涡旋进行研究,发现50~100 km涡旋主要分布在黑潮延伸体流轴两侧,气旋涡和反气旋涡的寿命、半径分布具有一致性。气旋涡多出现在35°N以北,反气旋涡在35°N以南比较集中,与尺度较小的中尺度涡旋分布特征较为相似。冬夏两季涡旋地理分布存在一定差异,主要与不同季节该区域海表温度梯度及风应力旋度的变化有关。35°N以南50~100 km涡旋数量的季节性变化与风速大小的季节性变化存在明显的正相关性。35°N以南50~100 km涡旋三倍半径内风速异常和风应力旋度归一化表明,气旋涡对应风速负异常而反气旋涡对应风速正异常,反气旋涡的产生依赖于风应力负旋度,气旋涡的生成与风应力正旋度有关。 相似文献
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Lin Hongbai 《海洋学报(英文版)》1989,8(4):601-603
The samples of Tunicata were collected from 41 stations in Kuroshio region. southeast of Japan(28°24′--36°30′N,129°--145°E), with a macroplankton net (15 meshes per cm, with a length of270 cm and an opening diameter of 80 cm) towed vertically from a depth of 200 m to the surface dur-ing the second cruise of China--Japan Joint Research of Kuroshio in October and November, 1986.Altogether 36 species were distinguished and counted. They are: 相似文献
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Based on the surface drifters that moved out from the Sea of Okhotsk to the Pacific, the surface velocity fields of mean,
eddy, and tidal components in the Oyashio region are examined for the period September 1999 to August 2000. Along the southern
Kuril Island Chain, the Oyashio Current, having a width of ∼100 km, exists with velocities of 0.2–0.4 m s−1. From 40°N to 43°N, the Subarctic Current flows east- or northeastward with velocities of 0.1–0.3 m s−1, accompanied by a meandering Oyashio or Subarctic front. Between the Oyashio and Subarctic current regions, an eddy-dominant
region exists with both cyclonic and anticyclonic eddies. The existence of an eastward flow just south of Bussol' Strait is
suggested. The 2000 anticyclonic warmcore ring located south of Hokkaido was found to have a nearly symmetric velocity structure
with a maximum velocity of ∼0.7 m s−1 at 70 km from the eddy center. Diurnal tidal currents with a clockwise tidal ellipse are amplified over the shelf and slope
off Urup and Iturup Islands, suggesting the presence of diurnal shelf waves. From Lagrangian statistics, the single-particle
diffusivity is estimated to be ∼10 × 107 cm2s−1. 相似文献
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Two suites of slumps from opposite margins of the Gulf of Mannar, between Sri Lanka and southern India, have met and coalesced.
The “Eastern Comorin” Slump is the more coherent of the two with a length of 70 to 100 km. The “Colombo” side slump consists
of two to four blocks 15 to 35 km in length. Both slump-suites decrease to the south. A paleoslump underlies the western toe
of the East Comorin Slump at a depth of some 800 meters. To the south, an enlarging and deepening submarine canyon marks the
area of slump coalescence. 相似文献
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Geology of the Continental Margin of Enderby and Mac. Robertson Lands, East Antarctica: Insights from a Regional Data Set 总被引：1，自引：0，他引：1
H. M. J. Stagg J. B. Colwel N. G. Direen P. E. O’Brien G. Bernardel I. Borissova B. J. Brown T. Ishirara 《Marine Geophysical Researches》2004,25(3-4):183-219
In 2001 and 2002, Australia acquired an integrated geophysical data set over the deep-water continental margin of East Antarctica
from west of Enderby Land to offshore from Prydz Bay. The data include approximately 7700 km of high-quality, deep-seismic
data with coincident gravity, magnetic and bathymetry data, and 37 non-reversed refraction stations using expendable sonobuoys.
Integration of these data with similar quality data recorded by Japan in 1999 allows a new regional interpretation of this
sector of the Antarctic margin.
This part of the Antarctic continental margin formed during the breakup of the eastern margin of India and East Antarctica,
which culminated with the onset of seafloor spreading in the Valanginian. The geology of the Antarctic margin and the adjacent
oceanic crust can be divided into distinct east and west sectors by an interpreted crustal boundary at approximately 58° E.
Across this boundary, the continent–ocean boundary (COB), defined as the inboard edge of unequivocal oceanic crust, steps
outboard from west to east by about 100 km.
Structure in the sector west of 58° E is largely controlled by the mixed rift-transform setting. The edge of the onshore Archaean–Proterozoic
Napier Complex is downfaulted oceanwards near the shelf edge by at least 6 km and these rocks are interpreted to underlie
a rift basin beneath the continental slope. The thickness of rift and pre-rift rocks cannot be accurately determined with
the available data, but they appear to be relatively thin. The margin is overlain by a blanket of post-rift sedimentary rocks
that are up to 6 km thick beneath the lower continental slope.
The COB in this sector is interpreted from the seismic reflection data and potential field modelling to coincide with the
base of a basement depression at 8.0–8.5 s two-way time, approximately 170 km oceanwards of the shelf-edge bounding fault
system. Oceanic crust in this sector is highly variable in character, from rugged with a relief of more than 1 km over distances
of 10–20 km, to rugose with low-amplitude relief set on a long-wavelength undulating basement. The crustal velocity profile
appears unusual, with velocities of 7.6–7.95 km s−1 being recorded at several stations at a depth that gives a thickness of crust of only 4 km. If these velocities are from
mantle, then the thin crust may be due to the presence of fracture zones. Alternatively, the velocities may be coming from
a lower crust that has been heavily altered by the intrusion of mantle rocks.
The sector east of 58° E has formed in a normal rifted margin setting, with complexities in the east from the underlying structure
of the N–S trending Palaeozoic Lambert Graben. The Napier Complex is downfaulted to depths of 8–10 km beneath the upper continental
slope, and the margin rift basin is more than 300 km wide. As in the western sector, the rift-stage rocks are probably relatively
thin. This part of the margin is blanketed by post-rift sediments that are up to about 8 km thick.
The interpreted COB in the eastern sector is the most prominent boundary in deep water, and typically coincides with a prominent
oceanwards step-up in the basement level of up to 1 km. As in the west, the interpretation of this boundary is supported by
potential field modelling. The oceanic crust adjacent to the COB in this sector has a highly distinctive character, commonly
with (1) a smooth upper surface underlain by short, seaward-dipping flows; (2) a transparent upper crustal layer; (3) a lower
crust dominated by dipping high-amplitude reflections that probably reflect intruded or altered shears; (4) a strong reflection
Moho, confirmed by seismic refraction modelling; and (5) prominent landward-dipping upper mantle reflections on several adjacent
lines. A similar style of oceanic crust is also found in contemporaneous ocean basins that developed between Greater India
and Australia–Antarctica west of Bruce Rise on the Antarctic margin, and along the Cuvier margin of northwest Australia. 相似文献