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111.
南菲律宾地区类埃达克岩和富铌玄武质熔岩的成因 总被引:7,自引:3,他引:7
PaternoRCASTILLO 《岩石学报》2002,18(2):143-151
埃达克岩(adakite)最初 是指由消减板片玄武岩物质熔融形成的富硅、富钠、高Sr/Y和La/Yb比值的弧火山熔岩。它通常产在会聚带,这个部位的年轻的、因而仍然是热的大洋板片正在发生俯冲消减。富铌的岛弦玄武央进则是吕等到高碱的镁铁质熔岩,它们相对于正常的岛弦玄武岩含有较多的高场强元素(HFSE)。这些玄武岩通常与埃达克央共生, 这一组合是直被用于论证他们的高HFSE含量是因为他们的地幔源区受到板片来源的熔体的交代。先前的区域研究结果表明,南菲律宾是埃达克岩和富铌岛孤玄武岩的一个典型产地。然而最近的详细研究显示,尽管该地区的一些岛弧火山岩是类埃达克岩的,但是它们很可能是来自地幔楔的母岩浆的分异作用的产物,而这里的地幔楔主要是受沉积来源的成分交代的,此外,菲律宾南部最典型的富铌熔岩中HFSE的富集,也很有可能是起因于似乎是西太平洋边缘特有的富集地幔组分的熔融。这些结果提出了如下问题:南菲律宾是否存在真正的板片来源的熔体?这里的富铌岛弧 熔岩是否起因于地幔楔被这种熔体交代? 相似文献
112.
HAN XiQiu QIU ZhongYan MA WeiLin & QIAN JiangChu Key Laboratory of Submarine Geosciences State Oceanic Administration Hangzhou China Second Institute of Oceanography 《中国科学D辑(英文版)》2009,(4)
Due to their slow growth rates, seamount Co-rich crusts are very difficult to date with high resolution and precision. This paper is to test the use of orbital pacing on the growth profile of crusts to determine high-resolution age and growth rate. Crust CB14 from the central Pacific Ocean was selected for this study. We first examined the growth pattern in detail under a reflected-light microscope and ascertained that the growth environment was stable for the sub-layer 1 (0-3 mm). We then used electron mic... 相似文献
113.
Distribution and expression in vitro and in vivo of DNA vaccine against lymphocystis disease virus in Japanese flounder(Paralichthys olivaceus) 总被引:1,自引:0,他引:1
Lymphocystis disease,caused by the lymphocystis disease virus (LCDV),is a significant worldwide problem in fish industry causing substantial economic losses.In this study,we aimed to develop the DNA vaccine against LCDV,using DNA vaccination technology.We evaluated plasmid pEGFP-N2-LCDV1.3 kb as a DNA vaccine candidate.The plasmid DNA was transiently expressed after liposome transfection into the eukaryotic COS 7 cell line.The distribution and expression of the DNA vaccine (pEGFP-N2-LCDV1.3kb) were also ana... 相似文献
114.
Immunostimulants may improve disease resistance of aquaculture animals by promoting the nonspecific immunity response of the organisms. Five types of saccharides, including chitosan, yeast polysaccharide, burdock oligosaccharide, seaweed polysaccharide and lentinus edodes polysaccharide, were screened for potential use as immunostimulants by using spectrophotometry. The saccharides were injected into Apostichopus japonicus, a sea cucumber, and the lysozyme and superoxide dismutase (SOD) activities of the coelomic fluid and epidermal slime were monitored in six consecutive days. The results show that the lysozyme activity of the animal's coelomic fluid was significantly stimulated on day 2, day 4 and day 6 after the injection of the saccharides (P<0.05). The effects of chitosan and yeast polysaccharide were the most notable. The lysozyme activity of the epidermal slime was significantly increased by chitosana, yeast polysaccharide, seaweed polysaccharide, and burdock oligosaccharide on day 1 and day 2 after the injection (P<0.05). The SOD activity of the coelomic fluid was significantly promoted by the saccharides on day 2 and day 4 post-injection (P<0.05), while the SOD activity of the epidermal slime increased on day 2. These findings indicate that chitosan and yeast polysaccharide are the most effective immunostimulants and potential healthy anti-disease feedstuff for A. japonicus. 相似文献
115.
The role of halted "baroclinic modes" in the central equatorial Pacific is analyzed. It is found that dominant anomaly signals corresponding to "baroclinic modes" occur in the upper layer of the equatorial Pacific, in a two-and-a-half layer oceanic model, in assimilated results of a simple OGCM and in the ADCP observation of TAO. A second "baroclinic mode" is halted in the central equatorial Pacific corresponding to a positive SST anomaly while the first "baroclinic mode" propagates eastwards in the eastern equatorial Pacific. The role of the halted second "baroclinic mode" in the central equatorial Pacific is explained by a staged ocean-atmosphere interaction mechanism in the formation of El Nino: the westerly bursts in boreal winter over the western equatorial Pacific generate the halted second "baroclinic mode" in the central equatorial Pacific, leading to the increase of heat content and temperature in the upper layer of the central Pacific which induces the shift of convection from over the western equatorial Pacific to the central equatorial Pacific; another wider, westerly anomaly burst is induced over the western region of convection above the central equatorial Pacific and the westerly anomaly burst generates the first "baroclinic mode" propagating to the eastern equatorial Pacific, resulting in a warm event in the eastern equatorial Pacific. The mechanism presented in this paper reveals that the central equatorial Pacific is a key region in detecting the possibility of ENSO and, by analyzing TAO observation data of ocean currents and temperature in the central equatorial Pacific, in predicting the coming of an El Nino several months ahead. 相似文献