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41.
2020年中国科学院地理科学与资源研究所建所80周年。回眸80年,从1940年重庆北碚成立的中国地理研究所,到1953年重新组建的中国科学院地理研究所和1956年成立的中国科学院自然资源综合考察委员会,再到1999年地理研究所和自然资源综合考察委员会整合形成现在的地理科学与资源研究所,几经变迁,历经三代人努力,研究所始终如一,求真务实,开拓进取,推动着地理科学与资源科学的创新发展,为国家建设发展和生态文明进步做出了重要贡献。适逢建所80周年,本文回顾地理资源所发展历程,总结取得的重要科研成果,并展望未来发展。  相似文献   
42.
As the largest siliciclastic sink in the South China block, the Triassic Nanpanjiang basin is generally thought of as a foreland basin related to Indosinian collision between the South China and Indochina blocks. Our basin analysis, spanning an eight years period, provides details of Lopingian to Middle Triassic stratigraphic fill and tectonic subsidence of the basin. Field observation and sedimentological analyses reveal that the basin was not filled by a monotonous turbidite system and suggest instead the development of five primary depositional units constituted by deep-water turbidite systems, mass-transport deposits, condensed drapes, shallow-water isolated carbonate platforms, and volcano-volcaniclastic rocks. The stratigraphic completeness of the basin, the coexistence of widespread but localized carbonate platforms within axially filled deep-water basin, tectonically generated cyclothems of transverse mass-transport deposits along intrabasinal faults and basin fill of extrusive rocks of bimodal composition together apparently call in question the claim that crustal shortening prevailed during the Late Permian to pre-Norian Triassic. Patterns of basin fill, differential tectonic subsidence and very high subsidence rate of the region adjacent to master fault are more closely match the pattern expected for extensional to transtensional basin in a back-arc setting. The crustal extension in the southwestern South China was not consistent with hypothesized Indosinian collision between South China and Indochina blocks, but more likely developed in response to northwestward subduction of the paleo-Pacific plate. Our results, combined with regional considerations, lead to a new model for the Triassic tectonic evolution of South China during Triassic assembly of the southeastern and eastern Asia.  相似文献   
43.
许阳贵  刘云刚 《热带地理》2019,39(6):855-868
利用拓展贸易引力模型,借助Eviews等工具分析了影响中国与“一带一路”沿线国家贸易规模的因素,以及中国对外直接投资的滞后性对双边贸易的影响。结果表明:1)中国与“一带一路”沿线国家贸易规模受到经济发展水平、市场规模、政治制度、贸易畅通性、便利性、中国对外直接投资、民间文化交流紧密度的影响;2)中国对外直接投资对于带动中国与“一带一路”沿线国家间的贸易规模具有正向作用,但其效应具有一定滞后性;3)中国对外直接投资对于带动中国与不同“一带一路”沿线国家贸易规模的引力大小不同,可分为投资带动力巨大型、投资带动型、投资一般型、投资带动力不足型4种类型,中国与东南亚、西亚和撒哈拉以南的非洲国家贸易规模受中国对外直接投资带动作用较强。  相似文献   
44.
China’s tourism industry has witnessed rapid progress in recent years, and is now an important part of global tourism in dealing with climate change. Within a framework of Pressure-State-Response (PSR), this paper focuses on the emission reduction pressure, carbon emission status, and responses of stakeholders in China’s tourism industry. Findings include: 1) The central government’s strategy and rapid growth of the industry scale exert rising pressure on China’s tourism to reduce carbon emissions. 2) Carbon emissions of China's tourism account for 13%-14.6% of global tourism, and about 3% of China’s emissions overall. Chinese tourists’ per capita carbon emission is lower than half of the global level. 3) The Chinese government attaches great importance to energy-saving and carbon emission reduction. In the tourism industry, documents, standards and other regulative measures have been issued to ensure that business practitioners set up green operational and managerial systems. In the field of tourism transportation, China's high-speed rail, new energy vehicles, and urban shared bicycles, have developed very rapidly in recent years, and they have effectively reduced the carbon emissions in traveling. Furthermore, this paper finds that Chinese tourists already have awareness and willingness for low-carbon tourism.  相似文献   
45.
Sillitoe(1995)蚀变岩帽(Lithocap)的定义为大范围富黄铁矿的硅化、高级泥化和泥化蚀变,在地质环境上位于古地表和浅成中-酸性岩浆侵入体之间。蚀变岩帽往往显示为突出的正地形,有助于寻找隐伏的斑岩矿化体。但蚀变岩帽在地表的范围往往多达几十个平方千米,又常常掩盖下覆斑岩矿床的蚀变矿化特征及其地球化学印记,因此大型的蚀变岩帽又给勘探工作带来一定的挑战。蚀变岩帽相关矿床的勘探需以地质填图为基础,结合近红外光谱分析(SWIR)进行蚀变填图,以及全岩地球化学以及矿物地球化学表现的元素或元素组合异常,来帮助定位热源或深部斑岩体。遥感和地球物理中的激电响应,也可以辅助定位岩体。华南地区的蚀变岩帽主要分布于长江中下游成矿带和东南沿海火山岩带。前人对安徽庐枞盆地中的矾山蚀变岩帽进行了系统研究,确定了矾山蚀变岩帽形成于白垩纪,与围岩砖桥组火山岩年龄一致。同位素和流体包裹体工作证明了形成矾山蚀变岩帽的流体主要为深部岩浆热液中的酸性气体与浅部大气降水的混合,在浅部高渗透率的火山岩及其岩性界面反应,广泛发育了一套硅化和高级泥化蚀变,指示与矾山相关可能存在斑岩和高硫型浅成低温热液铜金矿床。福建紫金山地区有中国最大的高硫型浅成低温热液矿床,主要赋存于紫金山蚀变岩帽中。紫金山蚀变岩帽的地质特征和蚀变分带已经研究的较为详细,但目前深部的侵入体还没有发现。浙江的蚀变岩帽是中国非金属矿产的重要来源,包括明矾石矿、地开石矿和红柱石矿等,这些蚀变岩帽与金属矿化的关系尚未有相关研究。根据目前的资料总结,有较多的蚀变岩帽分布在中国华南,这些蚀变岩帽特征典型,但目前的研究程度尚浅。现有的研究结果表明,华南的蚀变岩帽的成矿潜力巨大,可能存在一条巨型的斑岩-浅成低温矿床成矿带,具有广阔的找矿勘查前景,建议加强蚀变岩帽及相关矿床的找矿与研究工作。  相似文献   
46.
Integration of extensive fieldwork, remote sensing mapping and 3D models from high-quality drone photographs relates tectonics and sedimentation to define the Jurassic–early Albian diapiric evolution of the N–S Miravete anticline, the NW-SE Castel de Cabra anticline and the NW-SE Cañada Vellida ridge in the Maestrat Basin (Iberian Ranges, Spain). The pre shortening diapiric structures are defined by well-exposed and unambiguous halokinetic geometries such as hooks and flaps, salt walls and collapse normal faults. These were developed on Triassic salt-bearing deposits, previously misinterpreted because they were hidden and overprinted by the Alpine shortening. The Miravete anticline grew during the Jurassic and Early Cretaceous and was rejuvenated during Cenozoic shortening. Its evolution is separated into four halokinetic stages, including the latest Alpine compression. Regionally, the well-exposed Castel de Cabra salt anticline and Cañada Vellida salt wall confirm the widespread Jurassic and Early Cretaceous diapiric evolution of the Maestrat Basin. The NE flank of the Cañada Vellida salt wall is characterized by hook patterns and by a 500-m-long thin Upper Jurassic carbonates defining an upturned flap, inferred as the roof of the salt wall before NE-directed salt extrusion. A regional E-W cross section through the Ababuj, Miravete and Cañada-Benatanduz anticlines shows typical geometries of salt-related rift basins, partly decoupled from basement faults. These structures could form a broader diapiric region still to be investigated. In this section, the Camarillas and Fortanete minibasins displayed well-developed bowl geometries at the onset of shortening. The most active period of diapiric growth in the Maestrat Basin occurred during the Early Cretaceous, which is also recorded in the Eastern Betics, Asturias and Basque-Cantabrian basins. This period coincides with the peak of eastward drift of the Iberian microplate, with speeds of 20 mm/year. The transtensional regime is interpreted to have played a role in diapiric development.  相似文献   
47.
为了探讨华北板块南缘中元古代沉积地层的时代归属和物质来源、区域古地理格局和大地构造特征,对豫西灵宝福地地区的高山河群进行碎屑锆石U-Pb年代学和锆石微量元素特征研究。获得的高山河群年龄最小(年轻)的单颗碎屑锆石 207Pb/206Pb 年龄值为1685±39 Ma,从而限制了高山河群最早沉积年龄不早于1700 Ma。结合上覆的龙家园组年代学标定(1594±12 Ma),将高山河群的形成年代限定为1700—1600 Ma,即中元古代长城纪的中晚期,属国际地质年表的“固结纪”。高山河群中碎屑锆石 207Pb/206Pb 年龄范围为1685—2751 Ma,呈现1850 Ma、2150 Ma、2300 Ma和2500 Ma共4个年龄峰值,对应于华北克拉通古元古代重要的地质事件,并且高山河群以1850 Ma和2500 Ma峰值年龄段的地质体为主要的物源区。根据高山河群与云梦山组碎屑锆石年龄频率对比,推测在豫西地区西侧存在以往报道较少的年龄为2500 Ma的地质体。根据熊耳群火山岩及其对应锆石的地球化学特征和熊耳期盆地动力学性质,并结合高山河群沉积相特征和沉积盆地构造属性,认为熊耳群形成于与“岛弧”共生的拉张性质的弧后盆地地区,而其上覆的高山河群为弧后盆地靠近大陆一侧的具有被动大陆边缘性质的滨浅海沉积。  相似文献   
48.
为探讨松辽盆地北部林西组地球化学特征、沉积环境及构造背景,对该区黑富地1井所钻遇的上二叠统林西组暗色泥质板岩进行主量元素、微量元素和稀土元素测试分析,结果表明:样品主量元素平均质量分数SiO2为65.05%、Al2O3为17.23%、CaO为2.58%、Na2O为2.84%、K2O为3.29%,K2O/Na2O值为0.20~3.48,A12O3/(CaO+Na2O)值为0.41~8.01;稀土元素w(∑REE)值介于80.68×10-6~215.59×10-6之间,平均值为173.41×10-6δEu值介于0.61~0.88之间,平均值为0.70,表现为Eu的负异常,δCe值介于0.91×10-6~1.01×10-6之间,为微弱的Ce负异常,LREE富集,HREE亏损;微量元素以亏损Nb、Ta、Sr,相对富集Rb、Ba、La、Ce、Pb、Nd、Sm为特征。样品元素分析和物源w(TiO2)-w(Ni)、La/Th-w(Hf)等判别图解表明,林西组沉积物源具有多样性,主要来源于上地壳长英质物源,还有少量来自中、基性岩火成岩物源区。样品微量元素标准化蛛网图,稀土元素球粒陨石标准化配分模式图,K2O/Na2O-w(SiO2)、Th-Co-Zr/10、F2-F1构造背景判别图及地球化学参数对比结果表明,松辽盆地北部林西组物源构造背景主要为活动大陆边缘和大陆岛弧,可能形成于靠近大陆岛弧的活动大陆边缘构造背景。林西组应形成于海陆过渡相到陆相环境,水体由半咸水逐渐转变为淡水。  相似文献   
49.
本文采用中国沿海地区13个探空站2010~2014年实测地表温度Ts与平均温度Tm数据,利用傅里叶级数分析法精化中国沿海地区Tm模型,并将2015年探空站实测Tm数据与精化模型进行对比检验。结果表明,精化模型在Tm探测方面具有更高的计算精度,其计算大气可降水量的误差概率分布趋近于正态分布,具有较强的稳定性。  相似文献   
50.
The Central Pontides (northern Turkey) is one of the key localities to understand the geodynamic evolution of the Palaeo- and Neotethyan oceans. It consists of the pre-Jurassic basement units, the Early Jurassic and the Early Cretaceous accretionary complexes, the widespread Middle Jurassic continental arc magmatics and the Late Jurassic to Tertiary cover units. The Early Cretaceous accretionary complex is represented by the Central Pontide Structural Complex and includes the Middle Jurassic oceanic units, which were metamorphosed during the Early Cretaceous. Apart from these oceanic units, a few metaophiolite and serpentinite fragments have been recognized within the basement units, which may represent the remnants of an older ocean. The pre-Middle Jurassic Devrekani Metaophiolite is the largest oceanic fragment and tectonically intercalated within/between the Devrekani Metamorphics and the Çangaldağ Metamorphic Complex. It is mainly composed of harzburgites, dunites with chromite veins and metagabbros, and cut by metabasaltic andesites and metadacites. Petrographically, the gabbro consists mainly of plagioclase and clinopyroxene, and displays phaneritic/porphyritic texture. In contrast, the metabasaltic andesite includes plagioclase and mica phenocrysts within a fine-grained groundmass. Also, the metadacite is composed predominantly of quartz, plagioclase, and mica minerals. Two different magmatic groups belonging to completely different tectono-magmatic settings have been geochemically determined based on the immobile trace element systematics. The metadacites and metabasaltic andesites are akin to continental arc magmatics and characterized by negative Nb and Ta anomalies and depleted HFSE relative to Th and La contents. However, the metagabbro samples display the geochemical signatures of boninitic rocks and characterized by highly depletion in HFSEs and REEs relative to N-MORB. The Devrekani Metaophiolite in the Central Pontides may represent another remnant of pre-Middle Jurassic oceanic crust generation and can be north-eastward continuation of the Permian-aged Almacık complex and the Boğazköy Metaophiolite fragment in the western Sakarya Composite Terrane. It may have been cut by intrusions of the extensive Middle Jurassic continental arc magmatism after its imbrication within the basement unit. The presence of pre-Middle Jurassic oceanic units may indicate that the Paleozoic ocean may have survived as the Jurassic Intra-Pontide Ocean between the Scythian Platform and Sakarya Composite Terrane during the Mesozoic time. Thus, the Intra-Pontide Suture may normally include the Palaeozoic and Mesozoic remnants of the long-lived northward subducting Tethyan ocean.  相似文献   
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