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郑继民 《中国海洋大学学报(自然科学版)》1978,(2)
海洋沉积物的工程性质(或广义称为物理性质)的研究,是当前海洋地质学一项重大的理论课题。今年全国自然科学规划会议对于这方面的研究给予了高度的重视和关注。 海洋沉积物与陆源沉积物相比,显示出明显的特点。首先从沉积物的物质成分上看,就有很大的不同。例如海洋沉积物含有比例很高的生物骨骼质和别的有机岩屑。充满海洋沉积物孔隙的是含盐很高的水流体。这种水流体,对沉积物的性质有重大的影 相似文献
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海洋沉积物动学性质的测量 总被引：3，自引：0，他引：3
海洋沉积物力学性质的测量是近年发展迅速的新领域,鉴于海洋开发之需要,对具有广阔陆架的我国,海洋沉积物力学性质的测量和海洋现场袖珍土工仪器的应用更显得尤为重要。本文就国外海洋沉积物研究及国内海洋沉积物研究和国内研制的袖珍土工仪器在实际应用中的情况作一概略介绍。 相似文献
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海洋沉积物含水率对部分碱金属及碱土金属元素含量的影响及意义 总被引：1，自引：0，他引：1
利用电感耦合等离子体光谱仪(ICP-AES)对海洋表层沉积物及上覆海水、海洋沉积物国家标准物质、陆地的水系沉积物及土壤国家标准物质进行检测以对比海洋沉积物含水率对部分碱金属及碱土金属元素分析结果所造成的影响。结果显示海洋沉积物含水率对钠离子影响最大,往往有超过50%的钠离子来自其中所含海水的贡献,而海洋沉积物含水率对钾、钙、镁的影响则较为微弱。因此,研究海洋沉积物化学组分时有必要考虑其所含海水对钠含量的贡献,以期达到不同海洋沉积物化学组分的可比性。 相似文献
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海洋沉积物作为生源要素氮的重要源与汇，在其生物地球化学循环中起着至关重要的作用。该项研究旨在查清海洋沉积物中氮的存在形态及其生态学意义。氮是生物生命活动必需的营养要素，海洋中的氮往往是海洋初级生产力的限制因子，氮的吸收与再生释放在估算海洋新生产力和生源要素的生物地球化学循环率上也有重要贡献。海洋沉积物中的氮作为海水中氮的重要供给源是海洋生物赖以生存的重要物质基础，对维持海洋生态平衡、修复失衡的海洋生态环境具有重要意义。但由于不同海区海洋沉积物的来源和环境不同，氮的形态和含量亦不相同，可被生物吸收和利用的数量就不相同，因此造成了不同海区生物种群和环境不同，进而影响生态环境。因此，研究海洋沉积物中氮的形态，了解各个形态与沉积物中生物种群及与环境的关系，确定其生物和化学活性，査清氮不同形态的生态学功能，对于深入探讨海洋生物资源可持续利用的方法和策略具有重要意义。本文主要阐述海洋沉积物中氮的存在形式与分布、氮的早期成岩和去营养化作用、硝化和反硝化作用以及氮与生物特定种群的关系等，探讨了影响海洋沉积物中的氮循环的主要因素，并分析了海洋沉积物中的氮与生态系的关系，以期对研究氮的海洋生物地球化学过程有所帮助。 相似文献
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厦门东渡港疏浚沉积物的吸附和溶出研究 总被引：5，自引：0，他引：5
海洋沉积物中金属的溶出和吸附的研究对了解金属在海洋中的行为和污染问题,有重要的意义。本文从动力学角度研究了厦门东渡港疏浚沉积物中重金属的溶出和富集,考察了沉积物—海水间重金属的交换作用。 相似文献
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在绝大部分研究海洋沉积物稀土元素地球化学的工作中 ,作为研究对象的是太平洋底质。我们认为其原因是太平洋中海洋成岩作用类型表现较明显。对此 ,巨大的海洋面积起了促进作用 ,因此海洋中物质分异程度较大 ,远洋环境和沉积物类型的多样性也较突出。大西洋沉积物稀土元素的行为研究较少。现有资料不能满足了解稀土元素在大西洋沉积物中的分布机制。众所周知 ,随着进入远洋区 ,钍堆积在沉积物中。这种堆积与沉积物中水成组分的增加有关。对于大西洋沉积物来说 ,有关钍含量的资料还相当少。大西洋中铁锰结核广泛分布。在加拿利、北美凹陷中 ,… 相似文献
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Fine-grained sediments from the Late Triassic Yanchang Fm. in the Ordos Basin (central China) were studied by core analysis and geophysical logging. Part of the mudstones in this formation are stratified, part of them are unstratified; the various mudstones can be subdivided into eight types on the basis of their structures and textures. They represent a variety of environments, ranging from delta fronts and subaqueous fans to deep-water environments. Part of the sediments were reworked and became eventually deposited from subaqueous gravity flows, such as mud flows, turbidity currents and hyperpycnal flows that easily developed on the clay-rich deltaic slopes. The sediments deposited by such gravity flows show abundant soft-sediment deformation structures. Understanding of such structures and recognition of fine-grained sediments as gravity-flow deposits is significant for the exploration of potential hydrocarbon occurrences. Because fine-grained deposits become increasingly important for hydrocarbon exploration, and because the sediments in the lacustrine Yanchang Formation were deposited by exactly the same processes that play a role in the accumulation of deltaic and prodeltaic fine-grained sediments, the sedimentological analysis provided here is not only important for the understanding of deep lacustrine sediments like the Yanchang Formation, but also for a better insight into the accumulation of fine-grained prodeltaic deep-marine sediments and their potential as hydrocarbon source rocks and reservoir rocks. 相似文献
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Host sediments may exert a significant influence on the formation of gas hydrate reservoirs. However, this issue has been largely neglected in the literature. In this study, we investigated the types, characteristics and the depositional model of the fine-grained gas hydrate-bearing sediments in the northeastern margin of the South China Sea by integrating core visual observations and logging-while-drilling downhole logs. The gas hydrate-bearing sediments consist dominantly of muddy sediments formed in the inter-canyon ridges of the upper continental slope, including hemipelagites, debrites (mud with breccia) and fine-grained turbidites. Cold-seep carbonates and associated slumping talus, muddy breccia debrites, as well as coarse-grained turbidites, may locally occur. Four classes and six sub-classes of log facies were defined by cluster analysis. Core-log correlation indicates that gas hydrates are majorly distributed in fine-grained sediments with high resistivity and low acoustic transit time (AC) log responses, which are easily differentiated from the fine-grained background sediments of high gamma-ray (GR), high AC, and low resistivity log values, and the seep carbonates characterized by low GR, high resistivity, high density, low AC and low porosity log values. The primary host sediments consist of fine-grained hemipelagic sediments formed by deposition from the nepheloid layers of river material and from the microfossils in seawater column. Most of the hemipelagic sediments, however, might have been extensively modified by slumping and associated gravity flow processes and were re-deposited in the forms of debrites and turbidites. Locally developed seep carbonates associated with gas hydrate dissociation and leakage provided additional sources for the gravity flow sediments. 相似文献
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A.S.G. Jones 《Marine Geology》1973,14(2):M1-M9
The concentration of copper, lead, zinc and cadmium in the acid-soluble fraction is presented for 86 seabed, 15 beach and 10 river samples of sediments from the southern Cardigan Bay area. Comparative results are presented for 8 samples of the Pleistocene sediments and 6 samples from the Aberystwyth Grits (Silurian) which outcrop along the shore line. The sediments from the Rheidol and Ystwyth rivers are strongly enriched in lead and zinc. The Pleistocene sediments are enriched in cadmium by a factor of 10 with respect to the seabed sediments in this part of Cardigan Bay. 相似文献
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Textural analysis is the epicenter of any sedimentological research. Granulometric analyses of unconsolidated sediments are used as an index to decipher the depositional environment. The granulometric analysis display a significant fluctuation in mean size, sorting, skewness, and kurtosis due to the variation in wave energy and the extent of turbulence affecting the beach environment during the crosshore and alongshore movement of sediments. The present study is to document the variation in grain size distribution within foreshore sediments, i.e., between the high water line and the plunge point wherein the sediments are deposited under different wave energy conditions. 相似文献
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湛江湾沉积物中反硝化和厌氧氨氧化细菌的丰度、多样性及分布特征 总被引：3，自引：0，他引：3
采用实时荧光定量PCR、高通量测序等方法对湛江湾沉积物中四个月份的反硝化细菌与厌氧氨氧化细菌的多样性和丰度进行了分析。结果表明:湛江湾沉积物中反硝化细菌和厌氧氨氧化细菌丰度在四个月份的变化和空间分布趋势为:nirS型反硝化细菌在二月份最高,四月份最低,且其平均丰度有从湛江湾湾内向湾口附近呈现先升高再降低的趋势;nirK型反硝化细菌丰度在九月份最高,十一月份最低;nosZ型反硝化细菌在四月份最高,其余月份变化不大;厌氧氨氧化细菌丰度在九月份最高,二月份最低。通过相关性分析结果表明,亚硝酸盐、铵盐等共同调控着湛江湾沉积物中反硝化和厌氧氨氧化细菌丰度变化。系统发育分析表明:湛江湾中存在着一些广泛分布的反硝化细菌,但也生活着一些新奇的nirK型和nosZ型反硝化细菌。对于厌氧氨氧化细菌而言,其主要属于浮霉菌门及Candidatus Scalindua属,具有较高的耐盐性,另外湛江湾海区的厌氧氨氧化细菌也生活着一类在其他地方没有的新分支。典范对应分析分析结果表明:硝酸盐显著影响湛江湾反硝化细菌和厌氧氨氧化细菌的群落结构。湛江湾沉积物中反硝化细菌和厌氧氨氧化细菌存在特殊的竞争与共存的关系,且由亚硝酸盐、硝酸盐、pH等多种环境因子共同驱动。 相似文献
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海底沉积物声学性质原位测量系统海上试验研究 总被引：1，自引：0，他引：1
提出了一种新的海底沉积物声学性质原位测量方法,介绍了新研制的海底沉积物声学性质原位测量系统。在青岛近海海域对该系统进行了海试,获得了各个站位的声速数据。将测得的各站位的声速与不同海域的沉积物声速进行对比分析,并对各个站位的声速与沉积物的平均粒径进行了相关性分析,发现与以往研究结果一致,沉积物声速与沉积物类型相关,不同类型的沉积物的声速有明显差异;声速与平均粒径相关性较好,粒径越大,声速越高。结果表明,利用海底沉积物声学性质原位测量系统测得的原位声速是正确的,它能快速准确地得到海底沉积物的声速值。 相似文献
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Surface sediments from the Saronikos Gulf were analyzed for their aliphatic hydrocarbon (AHC) and polycyclic aromatic hydrocarbon (PAH) content by gas chromatography – mass spectrometry (GC/MS). The concentrations of Fe, Cr, As, Sb, Co and Sc were also determined by neutron activation analysis (NAA). The survey was performed at the beginning of the operation of Athens’ sewage primary treatment unit and the results can be used to monitor the unit's long-term effects in the area. The composition of aliphatic hydrocarbons indicated a chronic oil-pollution in the Saronikos Gulf sediments. The industrially impacted Elefsis Bay sediments suffered from heavy petroleum pollution, while the sediments near the sewage outfall had a moderate degree of pollution. Mixed source patterns of polycyclic aromatic hydrocarbons with dominant pyrolytic inputs have been identified in the sediments. Total concentrations of Fe, As and Sb along with their Sc normalized values presented elevated values in Elefsis Bay sediments. Chromium was found enriched in the sediments near the Athens sewage outfall. Factor analysis results showed that a part of As and Sb in Elefsis Bay sediments could be associated with organic or sulphidic phases. In addition, the lithogenic fraction of the sediments and the Fe oxides/hydroxides were important trace element carriers. Chromium and PAH inputs from the sewage outfall were also detected. Comparison of PAH and trace element concentrations with internationally-used sediment quality guidelines (SQG) revealed that Elefsis Bay sediments had the greatest potential of causing adverse effects in benthic organisms. 相似文献
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珠江磨刀门河口底质沉积特征及其泥沙运移趋势 总被引：3，自引：0，他引：3
根据珠江磨刀门河口的表层沉积物粒度分析结果,运用Gao-Collins粒径趋势分析方法(GSTA模型),计算河口的沉积物净输运趋势,并分析河口底质沉积特征。结果表明:河口较粗的沉积物分布在交杯沙浅滩和拦门沙顶部,受波浪作用影响分选较好;磨刀门主槽、龙屎窟和口外海滨的沉积物则较细,以粉砂和粘土为主,分选稍差。沉积物在纵向和横向上都表现出细-粗-细的变化趋势。磨刀门主槽泥沙受强径流影响,具有向南的输运趋势;龙屎窟在涨潮流作用下,泥沙净向北输运;在西向沿岸流和东南向浪作用下,拦门沙东侧浅滩泥沙向西侧搬运,口外海滨的泥沙输运趋势则向北。 相似文献
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Distribution and dispersal pattern of clay minerals in surface sediments, eastern Beibu Gulf, South China Sea 总被引：3，自引：2，他引：1
Clay minerology of sediments are useful in determining distribution,sources and dispersal routes of fine-grained sediments.In the present paper,clay minerals of surface sediments throughout the eastern part of Beibu Gulf has been investigated to reveal sources and transport of detrital finegrained sediments.Four distinct clay mineral suites were observed from cluster analysis of clay mineral compositions of the samples.From the distribution pattern of clay minerals,we conclude that kaolinte in the eastern gulf is mainly derived from South China Landmass;Smectite could not be transported mainly by surface current from north-western Hainan Island,and maybe minor portion of it from Red River;Illite is mainly transported by the currents from South China Sea.Chlorite has two sources,namely South China Sea and South China Landmass.The Zhujiang River derived sediments could not be one of the sources for the clay mineral here,because of very different composition and ratios.The distribution pattern of clay minerals in the eastern Beibu Gulf is mainly controlled by fine-grained sediment source and local currents.The Silt/Clay,Smectite/Kaolinte,and Smetite/(Chlorite+Illite) ratios could be used as indicators of fine-grained sediment dispersal in the gulf. 相似文献
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福建洛阳江河口湿地沉积物粒度特征及其沉积环境意义 总被引：4，自引：1，他引：3
沉积物粒度是反映湿地沉积环境的重要指标之一．利用Mastersizer2000型激光粒度仪对取自福建洛阳江河口不同类型湿地的6根短柱状沉积物样品进行了粒度分析．结果显示，该地区沉积物基本为粘土质粉砂，红树林湿地内的沉积物最细，分选程度最好；互花米草湿地圈闭了大量水流带来的粗、细颗粒物质，导致平均粒径相对较大，分选相对较差．粒度参数的相关分析结果显示，平均粒径与分选系数的显著正线性相关，揭示了该地区水动力作用弱、物质来源单一的沉积环境，显著增加了河口湿地沉积速率． 相似文献