珠江口水体中铜与悬浮颗粒物相互作用的研究     

丘耀文  王肇鼎  张正斌  刘莲生 《热带海洋学报》1995,(4)

使用无机离子交换法研究珠江口水体中铜与悬浮颗粒物的相互作用，测出钢与悬浮颗粒物相互作用的ｐＨ曲线呈Ｓ形，其分级离子交换等温线是一种新的“台阶”型；从分级离子交换理论求得分级平衡常数Ｋ１为５．０，Ｋ２为７８．１，珠江口水体中铜的表观络合容量为０．９２μｍ及其条件稳定常数为３．５×１０７。  相似文献   

南海深海盆地沉积柱样中的浊流沉积     

陈峰  蔡锋 《台湾海峡》1992,11(4):339-344

本文根据南海深海盆地三个沉积柱样的粒度结构、地球化学、微体古生物等特征分析,深讨了南海深海盆地细粒沉积物的浊积现象。结果表明,位于南海北部陆架斜坡上KL37孔的浊流沉积现象并不明显;位于陆架斜坡和深海盆地交界处的KL29孔存在着大量的浊积层,属于浊流沉积和半远洋沉积环境;位于南海盆地中部的KL91孔虽然已属于远洋性沉积环境,但除出现火山灰沉积外,浊流沉积作用仍然是相当活跃的。  相似文献   

潮汐沉积率与沉积间断   总被引：16，自引：3，他引：16  

李从先  王平  范代读  李铁松 《海洋地质与第四纪地质》1999,19(2):11-18

在浙北奥陶系文昌组和长江三角洲开敞型淤泥质海岸非潮道潮汐纹层研究的基础上,得出与国外同类研究相近的沉积率。现代海岸进积速度和潮坪沉积的观察及测试证明,上述沉积率是难以置信的。现代潮坪观测表明,潮汐纹层在形成过程中即包含着改造,所保留的纹层占应形成数的不到１０％,其余９０％以上被侵蚀。小型层序是风暴和平静天气的产物,为风暴层序,与大小潮周期无关。其地层中保留的数量不到应生成数的１０％,其余９０％被改造。小型层序被侵蚀,其中的纹层随之消失。致使潮坪层序中保存的纹层数仅为应形成数的０．２％。被改造的纹层和单层留下的仅是侵蚀面,即小间断。在进行潮汐沉积高分辨率的研究时应充分重视沉积间断的作用  相似文献   

Study on copper complexing ligand concentrations in several China’s coastal waters     

GONG Haidong  ZHANG Zhengbin  LIU Chunying  LIU Liansheng 《海洋学报(英文版)》2006,25(1):64-77

Copper complexing ligand concentrations in the Daya Bay, Qingdao coast, Jiaozhou Bay, South China Sea and Huanghe Estuary waters were determined by the anodic stripping voltammetry technique. The distribution regularity and the relationship with other parameters were discussed. The results were as follows: Copper complexing ligand concentrations of the South China Sea were a little higher than those of other sea areas, and they were apparently higher than those of the ocean. Compared with the subsurface layer (SSL) in the sea surface microlayer copper complexing ligand concentrations showed an enrichment phenomenon, of which the mechanism is similar to dissolved organic matter. The metal complexing ligand concentration profiles of the South China Sea showed that the value in the sea surface was the highest, then it decreased with depth accruing, and a higher value appeared at the bottom. Copper complexing ligand concentrations were higher than those of cadmium and lead. Ligands in each sea area exhibited a complicated property. In short, the distribution regularity of copper complexing ligand concentrations in China' s coastal waters was consistent with that of other regions in the world. Meanwhile, the positive relationship between the copper complexing ligand concentrations and biological oxygen demand, chemical oxygen demand, dissolved organic carbon, and viscosity were found clearly.  相似文献   

Comparison of Strain-rate Dependent Stress-Strain Behavior from Ko-consolidated Compression and Extension Tests on Natural Hong Kong Marine Deposits     

Jian-Hua Yin  Chun-Man Cheng 《Marine Georesources & Geotechnology》2006,24(2):119-147

This article presents results from a series of K_o-consolidated compression and extension triaxial tests on specimens from undisturbed samples of Hong Kong Marine Deposits (HKMD). To investigate the strain-rate effects, a total of seven K_o-consolidated triaxial tests were conducted including four compression tests and three extension tests. After K_o-consolidation, the triaxial test specimens were sheared at step-changed axial strain rates under three different confining pressures of 50 kPa, 150 kPa, and 400 kPa, respectively. The step-changed strain rates were applied in the following order: +2%/h, +0.2%/h, +20%/h, -2%/h (unloading) and +2%/h (reloading) for the four compression tests and -2%/h, -0.2%/h, -20%/h, +2%/h (unloading) and -2%/h (reloading) for the three extension tests. The results are reported and analyzed in the paper. The results show that the strain rate effects, the stress-strain characteristics, and the effective stress paths of the specimens for tests in a compression state are different from those for tests in an extension stage. One order of magnitude increase in axial strain rate causes an average 8.6% increase in undrained shear strength for compression tests and a 12.1% increase for extension tests. It is also found that the failure mode of the specimens in compression is different from that in extension. The stress-strain behavior of specimens shows strain-softening and a clear shear band in compression tests, but strain-hardening without any clear shear band in extension tests for the same absolute value of axial strain.  相似文献   

等深流沉积研究现状与展望   总被引：6，自引：0，他引：6  

许文彬  徐茂泉  孙美琴 《台湾海峡》2004,23(3):394-402

本文根据国内外等深流及其沉积的研究成果,概述了它们的研究进展,且详细阐述了等深流沉积特征和沉积类型,并指出等深岩丘的发现是该领域最为重要、最具特色的突出成果以及等深流沉积研究的油气勘探意义.虽然随着深海钻探计划和大洋钻探项目的开展,等深流沉积研究取得了较大进展,但现代等深流沉积和古代等深流沉积的研究在一定程度上发展尚不平衡,仍存在着较多问题,尤其是在古代等深流沉积研究方面显得更为薄弱.最为重要的是,等深流沉积的识别是该领域研究的最大难题.因此,在其未来研究上,应注意运用地震波识别、遥感等现代科技调查手段,进行多学科综合研究,尽快建立一套完善的识别标志,如沉积学标志、古生物标志等,以促使其逐渐成为海洋沉积学中一个更为完善的研究领域.  相似文献   

Distribution of dissolved species and suspended particulate copper in an intertidal ecosystem affected by copper mine tailings in Northern Chile   总被引：1，自引：0，他引：1  

Santiago Andrade  James Moffett  Juan A. Correa   《Marine Chemistry》2006,101(3-4):203-212

The coastline near Chañaral in Northern Chile is one of the most highly Cu-contaminated zones in the world due to discharges from mining activities for more than 60 years. The speciation of Cu has been studied to determine the importance of organic complexation in highly contaminated areas, and to assess the likely physiological impacts of Cu on marine organisms. Dissolved Cu concentrations of up to 500 nM were measured, completely saturating organic ligands and leading to free Cu²⁺ concentrations in excess of 10^− 8 M. These values are higher than those reported in any other marine environment, and because they occur over an extensive area, provide a unique opportunity to study the effects of Cu on marine ecosystems and to see how Cu behaves when its speciation is predominantly inorganic. We found strong gradients in free Cu²⁺ between Chañaral and adjacent areas with lower Cu, where speciation is dominated by organic complexation. There is also a significant increase in the partitioning of Cu onto suspended particles in the contaminated areas, consistent with previous studies that showed that organic ligands stabilize Cu in the dissolved phase, whilst “excess” Cu is rapidly scavenged. Those high dissolved Cu concentrations persist in spite of solid phase partitioning and advective processes along this open-ocean coastline, suggesting that Cu inputs into the system are still very large. Measurements were made using anodic stripping voltammetry with a thin mercury film coated with Nafion, which previous workers have shown can mitigate ambiguity in the data arising from inadvertent reduction of organic complexes. Our findings suggest that this is a useful methodology for contaminated systems.  相似文献   

自组织竞争人工神经网络在砂岩型铀矿测井数据解释中的应用     

徐建国  ;吴显礼  ;王卫国 《国外铀金地质》2008,(2):114-118

详细介绍了自组织竞争人工神经网络模型结构、原理和钻孔岩性自动识别过程,给出了神经网络模型在钻孔岩性自动识别过程中的有效性实例。自组织竞争人工神经网络具有自组织能力、自适应能力和较高的容错能力;与BP算法相比较,计算量小,收敛速度快,且不需要已知的先验信息而自动确定分类类别。钻孔岩性识别结果与岩心地质编录的对比试验表明,在砂岩型铀矿测井数据的解释中,应用自组织竞争人工方法可较好地完成钻孔岩性自动分类。  相似文献   

垣曲盆地最高阶地风尘堆积形成时代及其构造意义   总被引：1，自引：1，他引：0       下载免费PDF全文

傅建利  王书兵  蒋复初  蔡遥 《第四纪研究》2008,28(5):841-853

对垣曲盆地原土坪阶地剖面进行了详细的沉积学和磁性地层学研究,结果表明,原土坪剖面地层自下而上由水下河湖相-漫滩相-风尘堆积构成,整个剖面记录了一个水位下降、由水下沉积环境转变为气下环境的连续堆积过程。剖面地层记录的1.84～1.62MaB.P.期间由河湖相沉积环境转变为典型风尘堆积的沉积转型及风尘堆积反映出的1.21MaB.P.前后古气候变化事件是对青藏高原青藏运动C幕和昆黄运动的区域沉积响应。开始于1.62MaB.P.的典型风尘堆积底界年龄代表了该级阶地的形成时代,表明该段黄河至少在此时已经形成。  相似文献   

拉拉铜矿黄铁矿微量元素地球化学特征及其成因意义   总被引：6，自引：0，他引：6  

周家云  郑荣才  朱志敏  陈家  沈冰  李潇雨  罗丽萍 《矿物岩石》2008,28(3)

四川会理拉拉铜矿床是我国著名大型富铜矿床,针对该矿床中黄铁矿的微量元素、稀土元素地球化学分析表明:拉拉铜矿经历了早期火山喷发成岩成矿和晚期变质成岩成矿作用.条带状矿石中的黄铁矿Co/Ni比值集中于4.92～79.2之间,落入火山成因黄铁矿区,稀土元素分布具有Eu正异常和轻稀土富集的特征,反映矿床具有伴随河口群火山喷流沉积成岩过程的同生沉积成矿作用.脉状矿石中的黄铁矿Co/Ni比值集中于1.10～3.45,落在热液成因黄铁矿区,稀土元素较河口群岩石及其他典型块状硫化物矿床矿石稀土元素更加富集轻稀土元素,稀土含量变化范围更大,显著的负Eu异常,则又说明,矿床形成的主要成矿作用是伴随新元古代晋宁运动而发生的大规模的变质作用.  相似文献