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971.
海洋碳汇即蓝色碳汇,简称"蓝碳"。文章以21世纪海上丝绸之路建设为背景,以广东省蓝碳发展现状和需求为主线,分析广东省发展蓝碳对控制温室气体排放、保护海洋生态环境和实施"一带一路"建设的重要意义,论述发展碳汇渔业、修复典型海洋生态系统、控制陆源排放、开发可再生能源等蓝碳发展途径;在此基础上提出广东省发展蓝碳的主要对策,即完善政策保障体系、增强科技支撑能力、完善蓝碳产业链条、拓展国际交流合作、探索海洋碳排放交易试点、加强生态环境治理和发挥示范带动作用。 相似文献
972.
Coalbed methane (CBM) development in the southern Junggar Basin of Northwest China has aroused extensive attention owing to its significant resource potential. The accurate characterization of coal pore structure is important for CBM exploration and production. In order to explore the relationship between coal pore structure and macrolithotype, which has rarely been studied in the southern Junggar Basin, a series of laboratory experiments were performed on eight samples of different macrolithotypes. The results show that the porosity exhibits regularity with macrolithotype in the order bright < semibright < semidull < dull, and also shows an increase with the rise of the inertinite content. The pore-size distribution results show that the dominating pores of bright and semibright coals are usually greater than that of dull and semidull coals in size. The pore-type analysis indicates that the bottleneck pores (Type B) are well developed in dull and semidull coals, while bright and semibright coals mainly host two sides (Type A), namely opened pores and one-side-closed pores (Type C). The pore-type and -size distribution strongly affect pore connectivity refers to the facts that: 1) the proportion of effective porosity increases with an increasing proportion of pores greater than 100 nm in size; and 2) that the mercury withdrawal efficiency is always lower when the pores are mostly of Type B. So the pore connectivity of semibright and bright coals is higher than that of semidull and dull coals. Furthermore, pores are developed mainly in the inertinite, with pore-type being dominated by Type B and C, secondly in the vitrinite, with pore-type being dominated by Type A and C, and less developed in the liptinite with pore-type of B and C. The pore connectivity of each maceral is in the order vitrinite > inertinite > liptinite. Finally, according to the research results, the reservoir fracturing improvement should be more arranged on the dull or semi-dull coals, and the producing layers should be bright or semi-bright coals as much as possible on the premise that the gas contents of coal layers are not much different from each other. 相似文献
973.
974.
本文以太平洋CC区西区12个表层沉积物样品作为研究对象,对其粒度、化学组分和矿物成分进行分析,讨论其沉积环境和物质来源。研究区地处深海,主要以深海黏土和硅钙质黏土为主,含有少量的硅质黏土、黏土质硅质软泥和黏土质钙质软泥。黏土矿物成分主要是蒙皂石和伊利石,含有部分的高岭石和绿泥石。黏土矿物组成表明,区内沉积物主要是陆源,由高空气流携带而来,南极底流和热液活动对其物源的来源有一定影响。沉积物地球化学特征也表明,物源以陆源为主,稀土元素分布曲线和北太平洋表层海水稀土曲线类似,且表现出强的Ce亏损,表明生物活动导致的生物沉降对表层沉积物也有一定的影响。 相似文献
975.
《Marine Policy》2017
Transition to low carbon sea transport is a logical response to the extreme dependency of the Pacific Islands region on imported fossil fuel, its significant vulnerability to the effects of climate change and the critical shipping needs of Pacific Island countries (PICs). Building on previous work in low carbon sea transport in the Pacific, this paper further considers the barriers to achieving such transition by assessing, through a ‘post-Paris Agreement’ lens, the Intended Nationally Determined Contributions (INDCs) submitted by PICs and contrasting these to the near total lack of investment and planning for low carbon transition in the transport sector with the parallel occurrence in the electricity sector where ~USD 2 billion of donor investment is deployed or queued despite electricity using only ~20% of fossil fuel across the region. Consistent with recent international studies, inadequate and inappropriate financing and policy have been identified as dominant transition barriers for low carbon sea transport development in PICs. This paper further examines the regional level barriers to policy development, and finds them inhibited by the silo nature of the major regional actors. The implications that the Paris Agreement has for climate financing to support the essential research and capacity development needed to underpin a successful low carbon sea transport transition strategy at any useful scale and speed are also considered in this paper. 相似文献
976.
采用交通网络维数法、相关系数法和格兰杰因果检验分析法等定量统计方法,系统分析了自1998-2015年丝绸之路经济带九省区交通运输投资额、交通网络发育程度、交通运输能力的时空变化特征及对国民经济发展的影响。结果表明:丝绸之路经济带九省区交通运输投资额总体呈增长趋势,交通网络密度明显低于全国平均水平;交通网络发育程度不高,但增长发育速度较快,道路密度和网络维数均有很大幅度的提升,公路网的通达性水平及增速明显优于铁路网;交通设施建设对经济发展的影响显著,对国民生产总值的促进作用时滞长度为两年左右,但各省区之间的交通基础设施建设造成了不明显的空间溢出效应,体现出丝绸之路经济带各省区之间的经济联系尚处薄弱阶段。 相似文献
977.
对"一带一路"地区的能源金属锂和铀的矿床分布规律进行统计,并对典型矿床的地质特征与开发工艺进行概述,为了解"一带一路"地区的锂矿和铀矿提供基础信息,同时为中国进行"能源金属"的开采提供科学依据。研究认为,"一带一路"地区共有大型及以上锂矿36个,成因类型有硬岩型、盐湖型、沉积型和煤伴生型4种,资源储量分别为784×10~4t、1702×10~4t、237.5×10~4t和623×10~4t。盐湖型锂矿分布于中国和阿富汗,硬岩型锂矿分布在俄罗斯等国家,沉积型锂矿分布在塞尔维亚等国家,煤伴生型锂矿只分布于中国。鉴于盐湖型锂矿开发的环境影响较小,建议有关国家加大对盐湖型锂资源的勘探与开发。"一带一路"地区共有大型及以上铀矿130个,成因类型主要为砂岩型和火山岩型,主要集中在哈萨克斯坦等国家,铀资源储量(可靠回收成本≤130$/kg)达181.94×10~4t,占"一带一路"地区总资源储量的92.12%,建议中国与相关国家进行交流与合作,加大对中国境内北方地区砂岩型铀矿的寻找力度,同时进行火山岩型铀矿的勘探开发。 相似文献
978.
PGE mineralization and melt composition of chromitites in Proterozoic ophiolite complexes of Eastern Sayan,Southern Siberia 总被引:1,自引:1,他引:0
The Ospino-Kitoi and Kharanur ultrabasic massifs represent the northern and southern ophiolite branches respectively of the Upper Onot ophiolitic nappe and they are located in the southeastern part of the Eastern Sayan(SEPES ophiolites).Podiform chromitites with PGE mineralization occur as lensoid pods within dunites and rarely in harzburgites or serpentinized peridotites.The chromitites are classified into type I and type Ⅱ based on their Cr~#.Type I(Cr~# = 59-85) occurs in both northern and southern branches,whereas type Ⅱ(Cr~# = 76-90) occurs only in the northern branch.PGE contents range from ∑PGE 88-1189 ppb,Pt/Ir0.04-0.42 to ∑PGE 250-1700 ppb,Pt/Ir 0.03-0.25 for type I chromitites of the northern and southern branches respectively.The type Ⅱ chromitites of the northern branch have ∑PGE contents higher than that of type Ⅰ(468-8617 ppb,Pt/Ir 0.1-0.33).Parental melt compositions,in equilibrium with podiform chromitites,are in the range of boninitic melts and vary in Al_2O_3,TiO_2 and FeO/MgO contents from those of type I and type Ⅱ chromitites.Calculated melt compositions for type Ⅰ chromitites are(Al_2O_3)_(melt) = 10.6—13.5 wt.%,(TiO_2)_(melt) = 0.01-0.44 wt.%,(Fe/Mg)_(melt) = 0.42-1.81;those for type Ⅱ chromitites are:(Al_2O_3)_(melt) = 7.8-10.5 wt.%,(TiO_2)_(melt) = 0.01-0.25 wt.%,(Fe/Mg)_(melt) = 0.5-2.4.Chromitites are further divided into Os-Ir-Ru(Ⅰ) and Pt-Pd(Ⅱ) based on their PGE patterns.The type Ⅰ chromitites show only the Os-Ir-Ru pattern whereas type Ⅱ shows both Os-Ir-Ru and Pt-Pd patterns.PGE mineralization in type Ⅰ chromitites is represented by the Os-Ir-Ru system,whereas in type Ⅱ it is represented by the Os-Ir-Ru-Rh-Pt system.These results indicate that chromitites and PGE mineralization in the northern branch formed in a suprasubduction setting from a fluid-rich boninitic melt during active subduction.However,the chromitites and PGE mineralization of the southern branch could have formed in a spreading zone environment.Mantle peridotites have been exposed in the area with remnants of mantle-derived reduced fluids,as indicated by the occurrence of widespread highly carbonaceous graphitized ultrabasic rocks and serpentinites with up to 9.75 wt.%.Fluid inclusions in highly carbonaceous graphitized ultrabasic rocks contain CO,CO_2,CH4,N_2 and the δ~(13)C isotopic composition(-7.4 to-14.5‰) broadly corresponds to mantle carbon. 相似文献
979.
南极洲纳尔逊冰帽的某些动力学特征* 总被引:2,自引:0,他引:2
纳尔逊冰帽是南设得兰群岛的一个小冰帽,受海洋性气候影响冰帽上降水丰富,冰温较高。冰帽表面运动速度完全由冰帽表面形态和冰帽底床形态所控制,其中E剖面更为复杂。冰帽驱动应力基本小于100kPa.由V/Z~Za曲线得到在V/7为0.6~3×10-9范围内的流动参数:n约为1;B≈4.3×1010dynescm-2sec.这表明在低应力区,冰体流动更接近牛顿流体。 相似文献
980.
海底地震仪(Ocean Bottom Seismometer,OBS)数据处理至关重要,是获取深部地壳结构的基础与前提.2006年实施OBS2006-2测线时,有2台OBS(OBS03,OBS06)数据出现异常,无法使用.由于海上航次花费巨大,采集到的数据弥足珍贵.本文采用数据格式检查、邻近台站对比分析、重采样等方法,成功地对这2台OBS数据进行了解编处理,得到了这两个台站的综合地震记录剖面;利用上述方法对2011年实施的OBS973-3测线中的异常台站OBS03进行了分析处理,同样得到了OBS03台站的综合地震剖面;通过查看两次海上实验班报发现,OBS2006-2测线之OBS06与OBS973-3测线之OBS03内部Sedis编号相同,为同一台记录仪器,再一次验证上述处理方法正确可行;然后对OBS2006-2测线2个台站进行震相识别与走时拾取后,利用前人纵波速度模型开展了射线追踪与走时模拟.此次对异常OBS数据的重新处理工作,不仅为OBS探测提供了宝贵的数据处理经验,而且将提高OBS2006-2测线地壳结构的可靠性和约束性,具有重要的研究意义. 相似文献