The complex legal status of the Current Fishing Pattern Zone in the East China Sea     

《Marine Policy》2017

The purpose of this article is to analyze the legal status of fisheries in the East China Sea (ECS) pursuant to these fisheries agreements, focusing on the legal issues of the Current Fishing Pattern Zone (CFPZ) which is provided for in the Fisheries Agreement between Korea and China. The CFPZ is a zone or area in which Korean and Chinese fishing patterns that existed before the agreement are respected. Although the legal status of fisheries in the CFPZ appears to be very simple, it is in fact very complex due to the overlapping jurisdictions of Korea, China and Japan. Therefore, the fisheries regime is rather vulnerable with the possibility of increasing legal conflicts. However, it is noteworthy that fisheries conflicts come up rarely in these relevant waters. This article explores the bilateral fisheries agreements and EEZ laws of the respective states, and thereafter deals with the legal issues that arise in the execution of these agreements regarding the area of overlapping waters.  相似文献   

后弧（rear arc）岩浆作用的特征及其意义          下载免费PDF全文

袁方林  杨婧张旗  刘欣雨张成立 《地质科学》2017,(4):1388-1410

后弧岩浆作用（rear arc magmatism）是一个新的术语,国内文献大多认为与弧后（back arc）相当,也译为弧后。实际上rear arc 不同于back arc,前者仍然属于弧的范围,而后者已不属于弧结构。目前,对后弧岩浆作用的研究还十分有限, 原因一是 rear arc 出露较少,二是 rear arc 的鉴别标志不清楚。本文尝试对后弧玄武岩（rear arc basalt, RAB）作一个简单的介绍, 并采用对大量数据进行分析比较的方法与典型的岛弧玄武岩（IAB）和弧后盆地玄武岩（BAB）作一个对比。研究表明,后弧玄武岩主要由中-高 K 钙碱性和钾玄岩系列组成, 与典型的 IAB 和 BAB 相比, RAB 富集 Na₂O、K₂O、P₂O₅ ,贫CaO。后弧岩浆作用的微量元素具有典型的弧岩浆岩的特点,但LILE 及HFSE 比典型的岛弧岩浆的含量更富集,LREE 明显高于岛弧岩浆岩。 与岛弧岩浆相似,后弧岩浆同样具有明显的Nb-Ta 负异常。研究表明,上述3 类玄武岩很难区分开。但是,BAB 和RAB之间还是有一些不同的,如Sc/Nb-Ba/Y、Cu/P₂O₅-Y/Zr、Sc/Nb-Sr/Y 以及F₂O₃ /Zr-Y/Zr 等判别图。本文作者指出,后弧岩浆作用的提出完善了弧结构：一个完整的弧,从海沟向弧的方向,随着板块的俯冲作用,岩浆源区深度增加,地壳混染程度增加,依次出现前弧、弧和后弧岩浆作用, 至弧的后部,洋壳拉张,出现弧后盆地。前弧以玻安岩为代表,弧主要是IAB,后弧为碱性玄武岩,弧后则为MORB（+IAB 的印记）。显然,后弧岩浆作用的提出,对古造山带岛弧结构的恢复、古俯冲方向的确定是有积极意义的。  相似文献   

Geochronology,petrology and geochemistry of the Beiligaimiao magmatic sulfide deposit in a Paleozoic active continental margin,North China     

《Ore Geology Reviews》2017

The Beiligaimiao magmatic Ni-Cu sulfide deposit is located in the northern rim of the North China Block, which was an active continental margin related to the southward subduction of the Paleo-Asian oceanic plate to the north in the Paleozoic. This deposit has never been studied before but is an excellent example of sulfide mineralization in arc settings that have been commonly overlooked by exploration geologists worldwide. Sulfide mineralization in the deposit is hosted in a mafic-ultramafic complex that consists of a small ultramafic body surrounded by an older and much larger gabbroic intrusion. Disseminated sulfide zones are present in both intrusive bodies but only those close to the surface within the ultramafic body have been mined in the past. The sulfide-mineralized ultramafic body is composed of olivine websterite and orthopyroxenite with a gradational contact between them. SIMS U-Pb dating of zircon crystals from a large olivine websterite sample yields a crystallization age of 269.4 ± 2.1 Ma, which is ∼25 Ma younger than the Erbutu subduction-related magmatic Ni-Cu sulfide deposit that occurs ∼50 km to the north. Orthopyroxene crystals in the Beiligaimiao ultramafic rocks have Mg^# [100 Mg/(Mg + Fe), molar] of 77–78, significantly lower than those in the ultramafic rocks of the Erbutu deposit. Olivine crystals in the Beiligaimiao ultramafic rocks have forsterite (Fo) contents from 72 to 75 mol%, which are also significantly lower than those in the ultramafic rocks of the Erbutu deposit (Fo, 86–88 mol%). The mineral chemical data indicate a more fractionated parental magma for the former. Ca-depletion in olivine (i.e., <1000 ppm Ca), which is common for ultramafic cumulates in arc settings worldwide, is present in both deposits. Like Erbutu, the host rocks of the Beiligaimiao deposit are characterized by enrichments in light rare earth elements (REE) relative to heavy REE and pronounced negative Nb-Ta anomalies, consistent with ultramafic rocks in arc settings. The δ³⁴S values of sulfide separates from the Beiligaimiao deposit are 1.7 to 2.5‰, significantly lower than those for the Erbutu deposit but still slightly higher than the MORB value (−1.5 to 0.5‰). Olivine websterites in the Beiligaimiao deposit have ε_Nd from −8.9 to −9.5 and (⁸⁷Sr/⁸⁶Sr)_i close to 0.7075, which are similar to those of an enriched lithospheric mantle. An orthopyroxenite sample from the deposit has much lower ε_Nd (−12.6) coupled with much higher (⁸⁷Sr/⁸⁶Sr)_i ratio (0.7132), indicating ∼25% crustal contamination. The Sr-Nd-S isotope data support the premise that both crustal contamination and addition of crustal sulfur played a role in triggering sulfur saturation in the parental magma of the Beiligaimiao deposit. Since the immediate country rocks are exclusively gabbros, these processes likely took place at depth. The close temporal and spatial association of the Beiligaimiao and Erbutu deposits points to the possibility that more Permian arc-type magmatic sulfide deposits are yet to be discovered in the region.  相似文献   

电感耦合等离子体发射光谱法测定超贫磁铁矿和磁性物中有益有害组分及可选性评价     

黄瑞成  李灵凤  赵海  刘芳  魏灵巧  罗磊 《岩矿测试》2017,36(1):40-45

超贫磁铁矿是需要通过磁选富集后才能利用的铁矿石,磁性物是其磁选后的主要产品,磁性物中有益有害组分的含量是否满足规范要求是评价超贫磁铁矿可选性的前提,然而尚未引起足够的重视。本文采用电磁分选仪对超贫磁铁矿进行磁选,结合ICP-OES法对原矿和磁性物中有益有害组分(TFe、V_2O_5、TiO_2、P、Cu、Pb、Zn)进行了测定。结果表明,对于含量明显低于规范要求的V_2O_5、Cu、Pb、Zn,磁选后其含量虽有变化,但不影响冶炼及综合评价的结果;对于TFe、TiO_2、P,磁选后其含量发生明显变化,其中TFe由14.23%~16.60%提高至53.95%~69.86%,TiO_2由4.43%~5.02%降至0.84%~1.83%,P由0.11%~0.30%降至0.027%~0.048%,已对冶炼及综合评价的结果产生了影响,依据磁性物中TFe、TiO_2、P的含量更能切实反映超贫磁铁矿的可选性;所用超贫磁铁矿易于选别,通过单一弱磁选即可获得主要组分(TFe)及有害物质(P、Cu、Pb、Zn)满足炼铁用铁矿石工业要求的精矿;大部分TiO_2随弱磁选进入尾矿,后期应注意对尾矿中的TiO_2进行评价。该方法可快速获得超贫磁铁矿原矿及磁性物中有益有害组分的含量信息,既能从冶炼角度初步评价超贫磁铁矿的可选性,也可以确定后续综合利用研究的目标元素,对于超贫磁铁矿资源的合理开发利用具有重要的现实意义。  相似文献   

碱熔融-电感耦合等离子体发射光谱法测定高硫铝土矿中的硫   总被引：2，自引：2，他引：0  

胡璇  石磊  张炜华 《岩矿测试》2017,36(2):124-129

应用电感耦合等离子体发射光谱法(ICP-OES)测定高硫铝土矿(硫含量≤8%)中的硫时,由于硫存在-2、+4和+6等多种价态,常用的酸溶法和碱熔法处理高硫铝土矿时往往无法完全氧化硫而导致硫测定结果偏低。本文用过氧化钠熔融、热水浸取和盐酸酸化提取高硫铝土矿中的硫,使用基体匹配法绘制校准曲线补偿铝和钠对硫测定的光谱干扰,以S182.034 nm(184 nm)作为分析谱线,采用ICP-OES对硫进行测定。结果表明:3 g过氧化钠在700℃下熔融10 min,可以较好地氧化高硫铝土矿中的硫;校准曲线的线性相关系数为0.9999,方法检出限为0.025μg/m L,相对标准偏差(RSD,n=6)小于5%;与碳硫仪的测定结果相比较,两种方法无显著性差异。本方法溶样彻底,无样品损失,为今后实现应用ICP-OES同时测定高硫铝土矿中的硫和其他元素奠定了基础。  相似文献   

激光同位素光谱法测量水中氢氧同位素组成的实验室间比对研究   总被引：3，自引：3，他引：0  

蓝高勇  吴夏  杨会  唐伟  应启和  王华 《岩矿测试》2017,36(5):460-467

激光同位素光谱分析方法是近些年使用较广泛的一种便捷、快速的测试稳定同位素组成的技术,能同时分析出水中δD、δ~(18)O同位素组成,因其操作简单,检测效率高,体积小,野外现场测试携带方便,迅速在环境、地质、生态和能源等领域得到广泛应用,但是该测试分析方法尚没有相应的国家标准,测试结果得不到有效的溯源,在使用过程中缺乏规范和统一。为此,本文通过在全国范围内12家实验室选取8个比对水样(δD值在-189.1‰~-0.4‰内,δ~(18)O值在-24.52‰~0.32‰内),利用激光同位素光谱法测试比对D/H和18O/16O值,探讨激光同位素光谱仪分析水中δD、δ~(18)O值的准确度和精密度。测试结果表明:各个协作实验室数据准确、稳定,方法的重复性和再现性良好;激光光谱法测定的δD精密度为0.4‰(1σ),δ~(18)O精密度为0.05‰(1σ),与传统稳定同位素质谱的精度几乎一致,因此适用于常规水样中δD、δ~(18)O测定,可以开展野外在线实时检测水中氢氧同位素组成。本研究为开展制定激光同位素光谱法测定环境液态水中δD、δ~(18)O同位素组成标准方法的工作推广和应用提供了参考。  相似文献   

Stability analysis on a porous seabed under wave and current loadings     

Xiaoling Zhang  Guoliang Zhang 《Marine Georesources & Geotechnology》2017,35(5):710-718

The stability of a porous seabed under wave and current loadings is particularly important for engineers to design marine structures such as submarine pipelines, breakwaters, and offshore platform foundations. Most previous investigations of dynamic response of marine structures and seabed have only considered the influence of wave loading, but the important influence of current is ignored. Even if the influence of current is considered, the interaction mechanism of both loadings has not been clearly elaborated. Based on the Biot’s dynamic theory and combined two-dimensional nonlinear progressive wave and uniform current theory, the interaction mechanism of wave and current loadings and the influence of current on wave characteristic are analyzed by numerical computations. The influence of current velocity, different permeability, and stratification in seabed on the effective stresses and pore pressures of seabed is discussed in detail. Further, the stability of seabed is evaluated through the liquefaction analysis of seabed, which will provide important reference frames to improve the design and construction of marine structures.  相似文献   

Contributions of slab fluid and sediment melt components to magmatism in the Mariana Arc–Trough system: Evidence from geochemical compositions and Sr,Nd, and noble gas isotope systematics          下载免费PDF全文

Yasuo Ikeda  Keisuke Nagao  Teruaki Ishii  Daisuke Matsumoto  Robert J. Stern  Hiroo Kagami  Makoto Arima  Sherman H. Bloomer 《Island Arc》2016,25(4):253-273

This study presents new major and trace element, mineral, and Sr, Nd, and noble gas isotope geochemical analyses of basalts, gabbro, and clinopyroxenite from the Mariana Arc (Central Islands and Southern Seamount provinces) including the forearc, and the Mariana Trough (Central Graben and Spreading Ridge). Mantle source compositions beneath the Mariana Arc and the Mariana Trough indicate a mantle source that is depleted in high field strength elements relative to MORB (mid‐oceanic ridge basalt). Samples from the Mariana Arc, characterized by high ratios of Ba/Th, U/Th, ⁸⁴Kr/⁴He and ¹³²Xe/⁴He, are explained by addition of fluid from the subducted slab to the mantle wedge. Correlations of noble gas data, as well as large ion lithophile elements, indicate that heavy noble gases (Ar, Kr, and Xe) provide evidence for fluid fluxing into the mantle wedge. On the other hand, major elements and Sr, Nd, He, and Ne isotopic data of basalts from the Mariana Trough are geochemically indistinguishable from MORB. Correlations of ³He/⁴He and ⁴⁰Ar/³⁶Ar in the Mariana Trough samples are explained by mixing between MORB and atmosphere. One sample from the Central Graben indicates extreme enrichment in ²⁰Ne/²²Ne and ²¹Ne/²²Ne, suggesting incorporation of solar‐type Ne in the magma source. Excess ¹²⁹Xe is also observed in this sample suggesting primordial noble gases in the mantle source. The Mariana Trough basalts indicate that both fluid and sediment components contributed to the basalts, with slab‐derived fluids dominating beneath the Spreading Ridge, and that sediment melts, characterized by high La/Sm and relatively low U/Th and Zr/Nb, dominate in the source region of basalts from the Central Graben.  相似文献   

Quantitative Relationship Between Nitrous Oxide Emissions and Nitrogen Application Rate for a Typical Intensive Vegetable Cropping System in Southeastern China          下载免费PDF全文

Man Zhang  Zhao Zhi Chen  Qiao Ling Li  Chang Hua Fan  Zheng Qin Xiong 《洁净——土壤、空气、水》2016,44(12):1725-1732

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Ophiolites of the Central Asian Orogenic Belt:Geochemical and petrological characterization and tectonic settings     

Harald Furnes  Inna Safonova 《地学前缘(英文版)》2019,10(4):1255-1284

We present a compilation of published data(field,petrography,ages and geochemistry)from 73 ophiolitic complexes of the Central Asian Orogenic Belt.The ophiolitic complexes,ranging in age from Neoproterozoic to Triassic.have been geochemically classified as subduction-related and subductionunrelated categories applying recent,well-established discrimination diagrams.The subductionunrelated category is further subdivided into Mid-Ocean Ridge type(MOR),a common rift-drift stage and Plume type,and the subduction-related category is subdivided into Backarc(BA),Forearc(FA).Backarc to Forearc(BA-FA)and Volcanic Arc(VA)types.The four subduction-related types define highly different geochemical features,with the BA and FA types defining end members showing subduction influence of 10%-100%and 90%-100%subduction influence,respectively,and the two other types(BAFA and VA)define values between the two end members.The subduction-related category comprises79%of the examined ophiolites,of which the BA type ophiolites is by far the dominant group,followed by the BA-FA type,and with FA and VA types as subordinate groups.The Neoproterozoic and Ordovician complexes exhibit the highest,whereas those of Silurian age exhibit the lowest subduction-influence.Of the remaining 21%subduction-unrelated ophiolites,the MOR type dominates.Both the subductionrelated and subduction-unrelated types,in particular the latter,are commonly associated with alkaline basalts taken to represent ocean island magmatism.Harzburgite,dunite,gabbro and basalt are the common lithologies in all ophiolite types,whereas the BA-FA,FA and VA types generally contain intermediate to felsic rocks,and in the FA type boninites occur.The subduction-related ophiolites types generally show low metamorphic grade,whereas greenschist.amphibolite and blueschist grades occur in the subduction-unrelated and BA types.The highly different subduction contribution(from 0 to 100%in the MOR and FA,respectively),attest to variable dips of the subducting slab,as well as variable flux of subduction-related elements into the mantle above subducting slabs,from where the ophiolite magmas got their geochemical fingerprints.As most MOR ophiolites get subducted to the deep mantle,the subduction-related ophiolites have become a dominant ophiolitic type on Earth’s surface through all times supporting the idea about the early start of Plate Tectonics.  相似文献