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261.
O. Magnus Karlsson J. Mikael Malmaeus Sarah Josefsson Karin Wiberg Lars Håkanson 《Estuarine, Coastal and Shelf Science》2010
A dynamical, process-based mass-balance model was applied to quantify the transports of polychlorinated-p-dibenzodioxins and dibenzofurans (PCDD/Fs) to, within and from the Kallrigafjärden Bay, a coastal estuary in the Baltic Sea, and to predict the PCDD/F levels in the water and sediments of the bay. Before the modelling, a one-year sampling programme was implemented in 2007–2008 to measure the flows of PCDD/Fs in tributaries entering the system, the fluxes from the adjacent sea and the levels in water, sediment and fish within the estuary. The collected data set was used as input data to the model and for validation purposes. 相似文献
262.
罗马尼亚Vancea地震区是大陆上发生与板块磁撞和削减有关的中深部地震活动的地区之一。本文介绍了应用地震层析成象方法研究该地区深部速度结构成果。在研究中使用了地方和区域地震所记录的433个浅源和中部地震的到时资料反演求解深至200km的三维速度结构,在走时和射线路径的计算中利用了有效的三维射线跟踪技术,在反演中采用LSQR算法,高分辨率的地震层析图象揭示了速度结构的广泛不均匀性,结果表明,地震层析 相似文献
263.
在频率—波数域消除海上地震资料中的虚反射的一种方法 总被引:1,自引:0,他引:1
消除虚反射是海上地震勘探资料处理中的一个重要问题,本文提出一种在频率-波数域消除虚反射的方法,并给出了消除虚反射滤波因子的形式,然后利用此方法对合成地震记录进行了消除效果验证。 相似文献
264.
As one of the key safety problems, the motion performance and touching sea bottom of a FPSO are paid much attention by the ocean oil companies when the FPSO is exposed to survival storms in the shallow-water working areas. In this paper, timedomain numerical simulations are carried out on a 160 kDWT FPSO with a Yoke mooring system moored in the BZ25-1 oilfield with a water depth of 16.7m. The results are compared with those of the corresponding model tests. Good agreement shows that the time-domain simulations can be used to predict the performance of the FPSO in shallow-water reasonably. It is found that the touch of seabed by a fully loaded FPSO occurred few times under survival storm conditions. Therefore, the FPSO should be less loaded than that in the fully loaded condition under the survival storms. 相似文献
265.
266.
Over ninety surface sediment samples (0...3 cm) were collected in the Odra river estuarine system – from the Oderhaff, the Pomeranian Bight, the Peenestrom, the Greifswald Bodden – and the Arkona Basin between 1994 and 1996 and analysed for polychlorinated dibenzo-p-dioxins, dibenzofurans (PCDD/F) and biphenyls (PCB), and p,p′-dichlorodiphenyl-trichloroethane (DDT) including their metabolites. The contents of all investigated organochlorines in the sediments of the western part of the Oderhaff (Kleines Haff) were only slightly higher and more homogenously distributed compared to the values of the Pomeranian Bight and the Greifswald Bodden. PCB contents (sum of 23 congeners) in surface sediments ranged between <130 and 9 550 pg/g (given for dry weight, dw). The results of individual PCB congeners showed that high contents of hexa- and heptachlorinated compounds (PCB 138, 153, 180) were present in the entire area investigated. Generally, low levels of PCDD/F were found in surface sediments of the Odra river estuarine system due to small industrial activities in the catchment area. Contents of PCDF (sum) and PCDD (sum) varied from 2.5 to 820 pg/g (dw) and from 13 to 2 991 pg/g (dw), respectively. The congener contents of PCDF showed a nonuniform picture between the Oderhaff and the Arkona Basin. In contrast, the congener profiles of PCDD showed approximately similar patterns at nearshore and offshore stations, with highest values of OCDD (octa CDD). We assume that most of the particulate-bound micro-contaminants (PCB, PCDD/F) are deposited in the eastern part of the Oderhaff (Stettin Lagoon), which acts as a temporary trap and opurificationπ basin for the suspended particulate matter (SPM). One pathway for further transport of the particles seems to be the way on a small sedimentation strip along the island of Usedom via the “Saßnitz-trough” into the deeper parts of the western Baltic Sea. 相似文献
267.
中国荒漠区蒲公英属订正 总被引:1,自引:1,他引:0
《中国沙漠植物志》第3卷中,蒲公英属(TaraxacumF.H.Wigg.)只收载了9种,通过对中国荒漠地区蒲公英属标本鉴定和文献考证,认为中国荒漠地区该属植物有12种,并记载了每个种的产地和生境。 相似文献
268.
FN5井区夏子街组异常高阻段成因及油气成藏主控因素 总被引:1,自引:0,他引:1
通过岩心、薄片、构造演化史、古地貌等对FN5井区二叠系夏子街组异常高阻段进行综合分析.结果表明:FN5井区二叠系夏子街组异常高阻段发育2种岩性,高阻致密隔层以粗粒级云化凝灰质砂砾岩为主;低阻储层段以细粒级凝灰质细(中细)砂岩为主,储集空间具裂缝—孔隙双重介质特征.垂向上主要分布在夏子街组中部的P2x22砂层组;平面上主要分布在扇三角洲前缘近岸坡折带以下FC1—F20—FN055—FN5—W27井一带,面积为6.2km2,平面形态呈孤立的土豆状.油藏类型为东南方向受乌南断裂控制、其余方向受岩性控制的构造—岩性油藏.其展布受扇三角洲前缘的近岸水下坡折控制,后期成藏受控于异常高阻段的厚度及距主控断裂乌南断裂的距离.具有油层垂向厚度大、单井产量高、储量丰度高特征.为乌尔禾地区二叠系2011年探明储量培植及2012年增储上产的主要层位. 相似文献
269.
270.
In this article, we explore how Māori tribal organisations are responding to calls by other Indigenous peoples to become more sustainable in a time of climate change. From a close examination of tribal Environmental Management Plans, we move to a specific case study in the Bay of Plenty area, Ngāti Kea/Ngāti Tuara. Ultimately, we suggest that many tribal organisations are seeking to respond to climate change and transition to becoming producers of their own food and energy needs, and are often articulating these responses in relation to specific local resources and contexts. 相似文献