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91.
To understand the status of public awareness on wetland conservation in China,1237 people from 8 provinces or municipality were interviewed by questionnaire.After analysis of the results,88.5%of the interviewees know the word ’wetland’.TV and radio is the main tool for them to get information.More than two thirds of the respondents mainly learn the information on wetland conservation through TV and radio.There are still big gaps among different people in understanding wetland.Only 13.3%of the respondents give a completely right answer on question ’which areas are wetlands’.Most of the respondents cited lakes,marshes and rivers as wetlands,but more than half of them do not regard beaches,reservoirs,paddy fields and fish ponds as wetlands.Most of the people cited wetlands can provide such functions as water conservation,climate regulation,protecting wildlife,removing pollution, but know little about other functions such as flood control,provisioning of aquatic products,and soil retention, and much less about the cultural functions such as recreation,and inherited folk culture.Except for wastewater discharge, nearly half of the general public knows little about other threats of the wetland,while most of the people do not believe that artificial aquaculture will cause threats to the wetland areas.Public awareness on wetland conservation in China needs to be improved.Most of the respondents cited that TV,radio and internet are the most effective ways to publicize information on wetland conservation.More than two thirds of the respondents mainly learn the information on wetland conservation through TV and radio,while 38.0%of the respondents mainly through internet. Specifically,for farmers/fishermen,posters/picture albums can benefit them more than the internet;the undergraduates also expect to learn wetland mainly through posters/picture albums;while for the primary and middle school students, the school education is another valuable source of publicity in addition to TV and radio.Strengthen cooperation with TV stations and broadcasting stations are the best way to raise public awareness of wetland conservation. The authors suggest to strength cooperation with media on wetland conservation,conduct wetland conservation education in middle and primary schools and communities;organize experts and professionals to write books and teaching materials needed for popularizing science,basic education and staff training;develop an internet-based CEPA network system on wetland conservation;conduct public awareness activities in communities,focusing on females in rural areas;build public awareness and education system,improve the public’s awareness on wetland conservation,create good social environment for conserving wetlands.  相似文献   
92.
中亚及中国西部侏罗纪沉积盆地的构造特征   总被引:17,自引:5,他引:12       下载免费PDF全文
侏罗纪是中亚和中国西部地区沉积盆地主要形成时期,这表现在两个方面:(1)先期存在的盆地在此阶段沉积范围持续扩大;(2)形成了许多新的侏罗纪沉积盆地.本文通过对劳亚大陆南部侏罗纪特提斯北带构造特征、诸盆地早-中侏罗世岩相古地理和构造样式的分析,表明中国西部与中亚地区在侏罗纪时虽然都处于新特提斯北部被动大陆边缘,但由于受帕米尔弧向北推挤的影响,以及昆仑构造带与塔拉斯-费尔干纳断裂和阿尔金大型走滑断裂的存在,这两个地区的侏罗纪盆地具有完全不同的构造起因.以塔拉斯-费尔干纳断裂为界,西南侧中亚地区的侏罗纪沉积盆地主要是由新特提斯北部大陆边缘的被动伸展形成;东北侧中国西部的侏罗纪沉积盆地则主要发育于区域性挤压构造背景之下,形成的主要机制是重力陷落.此外,沿塔拉斯-费尔干纳断裂还存在几个侏罗纪的走滑拉分盆地.中国西部与中亚地区侏罗纪盆地的不同成因特征对盆地的比较研究和寻找侏罗系烃源岩都具有重要意义.  相似文献   
93.
气烟囱的形成机理及其与油气的关系探讨   总被引:11,自引:0,他引:11       下载免费PDF全文
气烟囱是由热流体活动形成的一种特殊的伴生构造.其一经形成后,对后期幕式活动的热流体或油气运移仍为一种特殊的运移通道,而且影响油气的聚集成藏.本文对气烟囱形成机理和演化特征进行了研究,探讨了气烟囱与油气生成、运移、聚集的关系,并通过光测弹性力学模拟和物理相似模拟等实验方法进行了验证.结果表明,在中国东部油气勘探中,气烟囱研究不仅可预测浅层油气藏分布,而且为寻找深层有机、无机气藏提供科学依据.  相似文献   
94.
应用多级平衡恢复原则,对浙西北地区褶皱-冲断构造样式及其组合进行缩短量计算与分析,同时,对前陆褶皱冲断带的变形缩短量和前陆盆地的缩短量及其二者关系进行了探讨,表明后者包容于前者之中.平衡缩短量与构造样式空间展布关系的研究表明前陆褶皱冲断带蕴含了递进变形的复杂过程,记录了造山作用及其挤压变形从初始→发展→顶峰→尾声的连续过程.综合分析表明缩短量自南东向北西呈递减趋势,即向前陆方向缩短量减少,与应变状态向前陆方向减弱是协调一致的.构造平衡及其综合分析是浙西北前陆褶皱冲断带向北西的构造极性的主要制约因素之一.  相似文献   
95.
Ancient Tethyan vestige extends from Alps, Kaebaiqn Mountain and eastward through Turkey, IranAfghanistan, and the middle and north of Tibetan Plateau, then turns to western Yunnan and Sichuan, andfinally ends at Zhongnan Peninsula. The PaleoTethyan is supposed as one eastward opened Oceanand superposed by tectonic deformation in the latestage of the late Mesozoic to Paleocene of Cenozoicand covered by Mesozoic and Cenozoic deposits. The Sanjiang region in southwestern China is in the…  相似文献   
96.
吴峻  兰朝利  李继亮 《地质通报》2005,24(12):1157-1161
木孜塔格蛇绿混杂岩沿东西走向的木孜塔格一鲸鱼湖断裂断续出露有变质橄榄岩、堆晶岩、火山岩及其上覆的硅质岩,彼此呈构造接触关系。其中,火山岩由玄武岩、玄武安山岩和安山岩构成。野外观察曾认为火山岩属于蛇绿岩的一部分.但火山岩的微量和稀土元素分析表明,其富集LREE、Cs、Ba、Th、Pb贫Nb,Ba/Nb、Ce/Pb、Cs/Rb、Ba/LaNb/Ta分别为18.59-102.82、1.42~8.13、0.10-0.49、11.76-51.79和6.22-13.58,TiO2含量1.64%-2.09%。这些特征表明该火山岩为形成于较成熟岛弧环境的火山岩而非蛇绿岩成员,也指示木孜塔格地区曾经历了与今西太平洋边缘近似的演化过程,可能形成了较成熟的沟-弧-盆体系。  相似文献   
97.
广西合山马滩大隆组的沉积序列研究及其环境指示意义   总被引:1,自引:1,他引:1  
马滩地区的大隆组,以火山碎屑岩和硅质岩沉积为主。镜下研究表明,火山碎屑岩可分为凝灰岩、沉凝灰岩和凝灰质沉积岩3亚类共8种岩石微相;硅质岩可分为生物成因硅质岩和生物火山成因硅质岩两亚类共5种岩石微相。这些岩石微相构成了12种主要的岩石相,而岩石相垂向上组成了6种主要的沉积序列。沉积序列指示该区存在两种类型的浊流沉积,一种是水下火山喷发形成的火山碎屑流向高密度浊流进而向低密度浊流演化的沉积,一种是早期沉积的凝灰质和硅质生物颗粒在滑塌作用下形成的浊流沉积。沉积序列研究并结合马滩地区大隆组沉积时期的古地形,表明当时该区不易发育海底扇沉积,而易接受低密度浊流沉积,形成了连续性好的较薄层沉积。  相似文献   
98.
Based on the stable isotopic analysis of more than 1000 samples of planktonic and benthic foraminifers from ODP Site 1148 in the northern South China Sea (SCS), the oxygen isotope stratigraphy has been applied to the last 3 million years for the first time in the SCS. Furthermore, the paleoceanographic changes in the northern SCS during the last 6 million years have been unraveled. The benthic foraminiferal δ18O record shows that before δ3.1 Ma the SCS was much more influenced by the warm intermediate water of the Pacific. The remarkable decrease in the deepwater temperature of the SCS during the period of 3.1-2.5 Ma demonstrates the formation of the Northern Hemisphere ice-sheet. However, the several sea surface temperature (SST) reductions during the early and middle Pliocene, reflected by the planktonic foraminiferal δ18O, might be related to the ice-sheet growth in the Antarctic region. Only those stepwise and irreversible SST reductions during the period of δ2.2-0.9 Ma could be related to the formation and growth of the Northern Hemisphere ice-sheet.  相似文献   
99.
The Upper Permian Dalong Formation (P2d) and Changxing Formation (P2C), and the Lower Triassic Zhengtang Formation (Tlz) are of deep-water turbidites. The sedimentary features of the NW Zhejiang are of SE-dipping passive continental margin from the Paleozoic to the early Triassic. Together with the foreland molasse basin during the late Triassic (T3w), the tectonics of the NW Zhejiang is characterised by a tectogenesis which took place in the middle Triassic. From SE to NW, the structural style varies from multi-duplex, antiformal stack to imbricate fans, and then to Jura Mountain-type fold zone with fold-style varying gradually from large-scale tight fold to midscale chevron fold, then to cylindrical fold, reviewing a preliminary scenario of foreland fold and thrust belt. The space-distributed structures and the tectonic vergence indicate the significance of deformation in (T1-T3). Project supported by the National Natural Science Foundation of China and Chinese Academy of Sciences.  相似文献   
100.
The Kudi ophiolite in the western Kunlun Mountains comprises harzburgites, dunites, cumulate dunites, cumulate pyroxenites and gabbros, diabase dikes, and pillow and massive lavas, and are fragments of a supra-subduction zone (SSZ) ophiolite from the Early Paleozoic. The extrusive rocks can be classified into three groups of tholeiites: back-arc basin (BAB) tholeiites, low-Ti island arc tholeiites (IAT), and LREE-enriched IAT, as shown by their distinctive geochemical characteristics. The SSZ-type mantle peridotites, the cumulate complex with arc tholeiite affinity, and BABB-type diabase dikes and basalts constitute an upper mantle and crustal section of a back-arc basin formed by coupling of MORB-type mantle upwelling with fluid efflux from slab devolatilization. The low-Ti IAT are characterized by low Ti and HFSE, and slightly U-shaped or LREE-depleted chondrite-normalized REE patterns, and represent melts derived from a depleted mantle source region (extraction of BABB magma) modified compositionally by fluids and/or melts from the subducting lithospheric slab during propagation and extension of the back-arc basin. We interpret the LREE-enriched IAT as products of closure of the back-arc basin because an interaction between the parental magma of this IAT and the mantle peridotites (formerly the upper mantle of the basin) in a newly formed mantle wedge had occurred.  相似文献   
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