便携式海底沉积声学原位测量系统研制及应用

详细介绍了最新研制的便携式海底沉积声学原位测量系统的工作原理和结构组成.与基于液压驱动的海底沉积声学原位测量系统相比,该系统操作简单,轻便灵活,易于吊放.2010年中国科学院南海海洋研究所“实验3”号科考船南海开放航次应用该系统在南海北部开展了海底沉积声学原位测量,首次获得该海区海底沉积物声速和声衰减系数原位测量数据.将原位测量声速与实验室测量声速进行了对比分析,结果表明二者存在明显差异,从而表明温度和压力等环境参数对沉积物声速具有重要影响.     

中国海区海底沉积物稀土元素地球化学

随着分析技术的进步以及海洋地球化学研究的深入开展,我国海区海底沉积物稀土元素研究也进入了新阶段。目前已对渤海、黄海、东海、南海及台湾浅滩等海区海底沉积物稀土元素地球化学作了较详细的研究。这些研究成果为探讨区域性沉积物的物策来源、形成环境及沉积物的对比提供了重要信息。     

红树植物花粉在我国东南部海域沉积物中的分布及古环境意义

为搞清我国陆架的孢粉、藻类分布规律，于１９７２年先后对黄海、东海、南海海底沉积物作了孢粉、藻类研究。结果表明，在黄海，东海表层沉积物中红树植物花粉主要由黑潮暖流北上携带而来，在南海沿岸的海湾和河流入海处沉积物中红树植物花粉含量高；水下古海岸线附近含量亦高，南海北部钻孔中的红树植物花粉系由海流搬运我国沿岸物质沉积而成；南部钻孔中的红树植物花粉主要是海流将马来西亚的菲律宾沿岸物质搬运沉积而成。     

海南岛东南外海海底沉积物特征及其声学物理性质研究

分析研究了南海北部大陆架西南缘的海南岛东南外海海底沉积物声学物理特性,在多个航次中进行了海底沉积层取样、海水CTD测量、浅地层及旁侧声呐扫测等工作.在实验室里对沉积物样品进行声学参数、沉积学基本参数、物理力学参数和14C年龄测试等分析.根据多尔特曼公式求解出弹性模量、体积弹性模量、压缩系数、切变模量、泊松比和拉梅常数等六项沉积物弹性参数.分析结果表明在该海区海底沉积物的压缩波速为1.474~1.700 m/s,在不同的海区内有高低声速两类性质的沉积物分布;沉积物的切变波速为150~600 m/s;沉积物在100 kHz的声衰减为35~260 dB/m;沉积物的密度为1.4~2.0 g/cm3;沉积物的孔隙度为42%~88%.     

岩心声速垂向变化对古海水进退的指示意义

钻孔岩心声速Cp垂向变化与地质历史中的海进、海退事件有关;南海北部大陆架及东海大陆架的钻孔岩心声速垂向变化曲线,为揭示西太平洋边缘海在更新世以来至少发生过3次海进和3次海退的3次沉积旋回事件提供了佐证。海进时所带来的海相沉积物的声速较低(1450—1510m·s-1),海退时所形成的陆相沉积物的声速较高(1650—1720m·s-1)。     

南海北部大陆架海底沉积物物理性质研究

用物理(声学的、工程地质的、扫描电子显微镜)等技术方法,综合分析了沉积物结构特征和工程力学性质,研究了颗粒接触、堆垒、孔隙等现象与物理性质之间的关系,得出了沉积物声学物理参数和应力一应变性质之间的关系。结果表明,南海北部大陆架海底沉积物有6种结构类型,其中混合接触结构类型的沉积物具有较高的抗压强度和声速,浅层海底存在着高、低声速分层的中尺度结构。     

海底沉积物的基本地声结构与地声模型

为准确建立海底地声模型,本文探讨地声模型的基本组成和基本结构。通过样品实验室测量,分析南海海底表层沉积物的密度、孔隙度与声速随着埋深变化的关系,得出海底实际存在的低声速表面–声速缓慢变化类型、低声速表面–声速增大类型、高声速表面–声速缓慢变化类型和高声速表面–声速增大类型4种典型地声结构;对比钻探测量,分析黄海海底沉积物的密度、孔隙度与声速随埋深变化关系,得出海底地声模型分层特征与地声结构组合特征。研究表明,地声模型可以归结为4种基本地声结构的组合,通过与底层海水声速、同层内声速剖面以及与上层海底沉积物下表面声速的比较,可以建立各种海底地声模型;基于实验室测量法建立的地声模型可以作为参考地声模型,但需要考虑实际海底温度和压力梯度以及海底沉积物的频散特性等,借助于声速比校正法和频散性理论模型进行计算及修正。     

南海北部海域表层沉积物中吸附气态烃的特征

根据１９９Ｏ年中德合作７２Ａ航次南海海洋联合调查资料，讨论了南海北部海区表层沉积物中吸附气态烃各组分的含量分布和组合特征，同时与我国东部海域（东海、黄海和渤海）作了比较。用Ｂｅｒｎａｒｄ（１９７８）和Ｆａｂｅｒ等（１９８４）关于海洋沉积物吸附气态烃成因的判断方法，探讨了本海区吸附气态烃的成因类型，首次报道了东沙群岛附近海域表层沉积物中吸附气态烃的特征。     

基于海底表层沉积物声速特征的南海地声模型

在由垂直声速梯度建立的地声模型基础上,通过引入沉积物与海水声速比和沉积物压缩波与切变波声速比两个表征沉积物声学特征参数得到更全面和有实际指导意义的地声模型。在沉积物声波传播FCMCM模型基础上,基于热作用和重力作用下沉积物两相介质的应力应变分析,建立TFCMCM和DFCFCM模型,运用模型校正表层沉积物声速特征来计算和解释地声模型。根据海底表层沉积物存在低声速和高声速两种类型,结合沉积物沿纵深孔隙度不变和变化两种类型,得到南海海底沉积物的两类四种典型地声模型:低声速孔隙度不变型、低声速孔隙度减小型、高声速不变型和高声速孔隙度减小型。运用这四种典型地声模型的组合解释了卢博提出的南海三种典型声速结构。认知声速结构将为南海声学探测海底、划分海底区域提供模型支持。     

渤海、黄海、东海沉积物中矿物组合的研究

本文对黄海、渤海、东海以及长江、黄河、辽河表层沉积物中的轻、重矿物进行了研究。分析资料表明,调查区内共有三种类型的矿物:陆源矿物、自生矿物和海底火山喷发形成的火山型矿物。根据轻、重矿物组合的差异,可把调查区分成8个矿物区。其物质来源主要为黄河与长江。黄河物质主要沉积在黄海、渤海;长江物质沉积在东海陆架区,而冲绳海槽则发现有海底火山喷发物质与浊流沉积。     

Distributions of nutrients in the East China Sea and the South China Sea connection

Surface maps of nitrate, phosphate and silicate of the East China Sea (ECS) have been constructed and are described. Reports on exchanges of material between the ECS and the South China Sea (SCS) through the Taiwan Strait are reviewed. Recent advances seem to have reversed the earlier view that the SCS exports nutrients to the ECS through the Taiwan Strait. This is because the northward flow of seawater in the summer carries little nutrient. On the other hand, the waters flowing southward along the coast of China in winter carry orders of magnitude higher nutrient concentrations. The outflow of subsurface waters from the SCS, however, is the major source of new nutrients to the ECS continental shelves because these subsurface waters flow out of the Luzon Strait, join the northwardly flowing Kuroshio and enter the Okinawa trough. Around 10% of the nutrients exported from the SCS through the Luzon Strait upwell onto the ECS shelf. These inputs are larger than the aggregate of all the rivers that empty into the ECS, contributing 49% of the externally sourced nitrogen, 71% of the phosphorous, and 54% of the silica for the ECS.     

我国南海历史性水域线的地质特征

40a的海洋地质、地球物理实测研究表明,九段线不仅是显示我国南海主权的历史性水域线,而且总体上也是南海与东部、南部和西部陆区及岛区的巨型地质边界线。根据实测数据,本文将从地质成因、来源、演化的角度论述此南海历史性水域线的合理性。主要结论包括:历史性水域线的东段在地形上基本与马尼拉海沟一致,海沟西侧为南海中央海盆洋壳区,东侧为菲律宾群岛。根据国际地质研究的资料,菲律宾群岛始新世以前位于较偏南的纬度,后来于中晚中新世(距今16~10Ma)仰冲于南海中央海盆之上,因此菲律宾群岛是一个外来群岛。而黄岩岛在马尼拉海沟以西,是中央海盆洋壳区的一个岛礁,与菲律宾群岛成因不同。南海历史性水域线的南段在地形上基本与南沙海槽一致,伴随南沙地块由北部陆缘向南裂离,古南海洋壳沿此海槽以南俯冲至加里曼丹岛陆壳之下,因此南沙地块与加里曼丹陆块为两个来历不同的地块。南海历史性水域线西段的分布在地形上与越东巨型走滑断裂带基本一致,可能与西沙地块、中沙地块、南沙地块从南海北部陆缘向南滑移有关。南沙地块北缘陡直的正断层结构,突显中央海盆是拉裂形成,其基底和中新生代地层与北部珠江口盆地的地层结构可以对比,说明南沙岛礁原属我国华南大陆南缘,后因南海的形成裂离至现今的位置。     

On a new Siphonophora from the East China Sea and South China Sea

In the course of identifying the samples of Siphonophora from the East China Sea and South China Sea, a new Siphonophora, Vogtia microsticella sp. nov. , was noted. The new species is distinguished from other five species in the genus in nectophore as follows: Parahorse-shoe shaped with five bluntly rounded projections, the two projections below the ostium, i. e. the basal projections, approach each other. The dorsal facet is smooth without any gelatinous prominence. Smaller are the nectosac and the ostium.     

Sediment transport in the Yellow Sea and East China Sea

Eight survey cruises in different seasons have been conducted in the Yellow Sea (YS) and East China Sea (ECS) during the period from 2000 to 2008. Suspended sediment concentration (SSC) and hydrological data were collected during each cruise. Data analysis showed that total suspended sediment mass was approximately 0.18 × 10⁹ tons in the surveyed area during spring and autumn seasons. Highly turbid waters were found in the shallow waters between the Subei coast, the Changjiang estuary and the Zhejiang coast with seasonal variations.     

Sediments in the East China Sea

This paper describes measurements of sediments during the 2000-2001 Asian Seas International Acoustic Experiment in the East China Sea. A number of techniques were used to infer properties of these sediments, including gravity and piston cores, subbottom profiling using a water gun, long-range sediment tomography, and in situ measurement of conductivity. Historical data from echosounder records and cores showed two regions of surficial sediments in the experimental area: a silty area to the west and a sandy area to the east. The tomography, cores, and water-gun measurements confirm the two surficial sediment regions seen in the historical data and also indicate that the subbottom structure at the experimental site consists of a thin (0-3 m thick) layer of sandy sediment directly beneath the sea floor. Below this layer, there is an extensive package of sediment with relatively uniform acoustic attributes. Core analysis shows that the surface sediment layer varies in compressional wave speed from a low near 1600 m/s in the west side of the experiment area to 1660 m/s in the east side of the experiment area. Long-range sediment tomography inversions show a similar spatial variation in the surface layer properties. In addition, the layer thickness as determined from tomography is consistent with the estimates from subbottom profiling.     

东海大陆架区海胆分类研究

海胆是重要的大型海洋底栖生物类群之一，某些海胆既是人工养殖对象，又是捕捞对象。因此，对海胆进行分类研究，摸清其地理分布特点，对合理利用海胆资源以及生物多样性研究都可提供基本科学依据。 对我国海胆的分类学研究始于1948年，当时张凤瀛先生对青岛的6种海胆进行了描述(张凤瀛，1948)。1957年张凤瀛和吴宝铃先生对广东沿海的37种海胆进行了研究(张凤瀛等，1957)。张凤瀛先生等1964年在《中国动物图谱，棘皮动物门》中记录了30种我国常见海胆(张凤瀛等，1964)。廖玉麟先生在20世纪70年代对西沙群岛的棘皮动物进行了分类研究，其中包括26种海胆(廖玉麟，1978)。 中国科学院海洋研究所于1958-1982年在东海大陆架进行过多次的综合性海洋调查。调查范围:26°~33°45′N，122°~129°E。该海域的底栖生物种类繁多，多样性丰度高。本文对中国科学院海洋研究所历年采自东海大陆架的海胆进行了较系统的研究，共包括21种，隶属于7目、11科、17属。其中有11种在我国是首次记录。名录如下，有*者为新记录。     

Trichodesmium in the East China Sea

A study is made on the surface distribution ofTrichodesmium thiebautii Gomont in the East China Sea during the years 1961–1967.

1. This alga is very scarce or absent in the period from January to March, and begins to increase in May and June, reaching the maximum population density from July to September, and again decreases in October and November.
2. In summerT. thiebautii is predominantly distributed in the area along the Kuroshio current with high densities of 10²–10³ filaments/l, occasionally exceeding 10³ filaments/l. This alga is estimated to occupy the major part or almost all the parts of chlorophylla in situ contained in the surface water of this season.
3. The occurrence ofT. thiebautii off the southern coasts of Central Japan seems to be caused rather by the multiplication in its own habitat than by the transportation by the Kuroshio current from the East China Sea.

     

Autumn living coccolithophores in the Yellow Sea and the East China Sea

An investigation was carried out on living coccolithophores(LCs) distribution in the Yellow Sea and the East China Sea from October 17 to November 24, 2011. A total of 223 samples from different depths were collected at 48 stations. Totally 18 taxa belonging to coccolithophyceae were identified using a polarized microscope at the 1 000× magnification. The maximum species abundance was found at the outside of Transect P. The dominated species were Gephyrocapsa oceanica, Emiliania huxleyi, Helicosphaera carteri, and Algirosphaera robusta. The abundance of coccoliths and cells ranged 0–2 965.73 coccoliths/mL, and 0–119.16 cells/mL, with the average values of 471.00 coccoliths/mL and 23.42 cells/mL, respectively. The LCs in surface layer were mainly observed on the coastal belt and middle part of the survey area. The comparison among Transects A, F, P and E indicated lower species diversity and less abundance in the Yellow Sea than those of the East China Sea. The highest abundance of LCs was found in transect F and P. The coccolith abundance increased slightly from surface to bottom in the water column, but the highest value of the cell abundance was observed in the depth of 10–30 m. Temperature, depth and nutrient concentration were suggested as the major environmental factors controlling the distribution and species composition of LCs in the studying area based on canonical correspondence analysis(CCA).     

2004年东海及黄海部分海域表层水温分布状况

分析了2004年东海及黄海部分海域表层水温的分布状况,结果表明,不同水团具有不同的温度年变化,大陆水系的均极差远大于多年平均值,说明沿岸海域的表层水温该年变化比常年大,但黑潮主干区的均极差却比多年平均值低;夏季沿岸海域以及中间水域出现了异常的高温现象,在8月,浙江沿岸、江苏沿岸、长江口以及福建部分沿岸海域的表层水温都突破了近20年的历史最高纪录;在春末、秋末沿岸海域表层水温远高于多年平均值.在暖流区域,除冬季的表层水温高于常年外,其它时间与多年平均差不多,所以年变化相对较小.     

黄、东海环流的数值研究Ⅰ. 黄、东海环流的数值模型

首先依据拉格朗日环流理论与黄、东海的环流物理和几何特征建立一个黄、东海环流的动力学统一模型 ,并按其无因次方程的量阶分析获得其零阶和一阶模型方程。最后依此模型方程的数学、物理特征确立了流速分解方案 ,从而形成完整的黄、东海拉格朗日环流数值模型。该课题组已完成较系统地对黄、东海环流的数值研究。该篇论文为系列报道之首篇。