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1.
沈炎彬 《极地研究》1988,1(2):66-66
南极生物群起源与演化国际学术讨论会,于1988年5月24—26日在伦敦举行.会议由英国地质学会、古生物学会、南极调查所和国家科学基金会极地项目部联合举办.会议内容涉及生物的起源;冈瓦纳古陆分裂、气候变冷、冰川作用、火山活动、极地长夜、洋流温度与生物演化和发展之间的关系.  相似文献   

2.
朱建钢  张洁 《极地研究》2007,19(3):244-245
2007年9月3—8日,SCAR-COMMNAP南极数据管理联合委员会第11届大会(JCADM-11)在意大利罗马举行,来自荷兰、英国、美国、意大利、法国、南非、比利时、德国、新西兰、挪威、澳大利亚、阿根廷、马来西亚、韩国和中国等20个国家的代表出席了本次会议,GCMD(全球变化主目录)也派特约代表出席了会议,本次大会是历届会议中出席代表最多的一次。首先,JCADM主席回顾了过去一年所做的工作。取得的进展有:在数据管理方面,数据目录从2006年的3000余条增加到目前的4300多条;中国南北极数据中心在2006年—2007年7月期间向AMD(南极主目录)提交元…  相似文献   

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(一)1983年12月5—7日,联合国教科文组织岩石圈保护学术委员会第三次会议在莫斯科举行(第一次会议于1981年6月1—3日在巴黎举行,第二次会议于1982年5月3—7日在布拉格举行。我所周必凡和丁锡祉同志分别参加了这两次会议)。学术委员6国10人(苏3人,美、法各2人,中、日、捷各1人),联合国官员2人以及英国、法国、联邦德国和苏联17名科学家以观察员身份参加了会议。苏联地质部部长E.A.柯兹洛夫斯基和教科文组织地学司司长V.谢尔巴瓦主持了会议。这次会议的议程之一是讨论《滑坡和泥石流》专著的定稿及出版问题。会议认为,经6国(日、美、苏、中、英、法)6人编委于1983年7月24日至8月2日在东京全面审定并作了适当修改补充后,该专著第一卷——基础理论部分可以在1984年出版,而第二卷——区域性问题仍需在近期再举行一次编委会审定。《滑坡和泥石流》这一专著的出版,将有助于加强各国科学家在这一领域的学术交流,并促进研究水平的提高。  相似文献   

4.
南极条约     
1959年12月1日,参加国际地球物理年(IGY)南极考察的十二个国家(阿根廷、澳大利亚、比利时、智利、法国、日本、新西兰、挪威、南非、苏联、英国和美国)于华盛顿签定了《南极条约》.  相似文献   

5.
在本届南极地球科学讨论会(1987年8月24—28日)期间及会后,南极研究科学委员会(SCAR)分别举行了南极地质制图学、火山岩地质及岩石学、南方高纬度新生代古环境演化、南极岩石圈结构与演化四个专家组正式会议.由于时间冲突,笔者未能参加古环境会议.制图会议对讨论会上展示并向SCAR提交的图件逐一审议.其中地质图均为小范围大比例尺图,如巴西提交的乔治王岛菲尔德斯半岛地形地质图(1∶1.5万);地球物理方面以航磁图为多;最引人注目的是大面积遥感图,利用卫(航)片经数据处理清晰地反映出地质构造或冰盖结构特征.会议着重讨论了今后几年计划实现的16幅图件(地质6、地球物理6、遥感3、水文1),其中主要有“南极地质全图”(1∶1千万,Tingey主编,“斯科舍弧构造图”(1∶3百万,J.W.Thomson主编),“罗斯海、威得尔海构造及地震剖面图”(比例尺未定,K.Hinz主编),“南极半岛地区地震剖面及地质图”(比例尺未定,C.O.Berbert主编)等.当讨论新遥感图件协调问题时,几家大公司代表就“LANDSAT”、“SPOT”、“AVHRR”等卫星及数据处理性能优劣争论激烈,并都希望由本公司承担这一任务.  相似文献   

6.
康建成 《极地研究》2000,12(2):96-96
“2 0 0 0年国际北极科学峰会周”( ASSW,Arctic Science Summit Week2 0 0 0 )”活动于 2 0 0 0年 4月 1~ 7日在英国剑桥大学 Selwyn College举行。本次活动由英国国家南极局主办。欧洲极地理事会 ( EuropeanPolar Board,EPB)、国际北极科学委员会 ( International Arctic Science Committee,IASC)、北极研究行动者论坛 ( Forum of Arctic Research Operators,FARO)、北冰洋科学理事会 ( Arctic Ocean Science Board,AOSB)、北极钻探 ( Nansen Arctic Drilling,NAD)、北欧极地会议 ( Nordic Polar Meeting) ,同时在此…  相似文献   

7.
颜其德 《极地研究》1997,9(2):84-84
第21届南极条约协商国会议在新西兰克来斯特切奇市召开第21届南极条约协商国会议(ATCM)大会于5月19~30日在新西兰克来斯特切奇市召开。来自南极条约体系的26个南极条约协商国的代表参加了会议。中国以外交部条法司、国家海洋局极地考察办公室联合组成中...  相似文献   

8.
南极天气预报业务的进展   总被引:6,自引:1,他引:5       下载免费PDF全文
卞林根  张雅斌 《极地研究》2000,12(3):219-232
第一届南极天气预报国际会议于 1 998年 8月 31日至 9月 3日在澳大利亚霍巴特举行。来自澳大利亚、比利时、中国、法国、意大利、俄罗斯和英国的 40多位代表出席了会议。近年来 ,随着综合科学考察的增多和南极旅游业的快速发展 ,对南极地区天气预报的需求有了很大的增加。许多南极考察站已使用了复杂的预报系统 ,浮标和自动观测站获得的数据、数值天气预报产品、高分辨率的卫星图像都得到有效利用。数值天气预报在预报发生在大洋和海岸附近天气尺度的低压方面取得了很大进展 ,但对当地预报非常重要的许多中尺度系统 ,在模式中还不能反映出来 ,系统的活动主要通过卫星资料来预报。期待将来能够选择南极的某些地区来运行高分辨率的有限区域模式。会议表明 ,随着近年来对高纬地区的天气过程的进一步认识、高分辨率的卫星图像和数值天气预报产品的使用 ,南极地区的天气预报已取得了长足发展。目前存在的突出问题是 :南极以外的气象中心很难得到南极的资料、南极半岛及内陆缺少高空资料、数值预报对南极地形和高纬过程的模拟效果不好等。会议的主要成果是将完成整个南极地区的天气预报手册  相似文献   

9.
由中国科学院和中国科学院地理科学与资源研究所联合主办的中国科学院城市地理国际研讨会(UGCAS2009)于2009年9月8-9日在我所成功举行.来自日本、美国、新加坡、香港及国内众多单位的城市研究学者参加了会议,正式参会代表大约80余人.  相似文献   

10.
罗玮 《极地研究》2018,30(4):450-452
正南极研究科学委员会(The Scientific Committee on Antarctic Research, SCAR)和国际北极科学委员会(The International Arctic Science Committee, IASC)联合会议POLAR 2018会议,于2018年6月15—26日在瑞士达沃斯召开。南极研究科学委员会(SCAR)、北极科学高峰周会议(ASSW)和南北极联合科学大会(Open Science Conference)由瑞士联邦森林、雪和景观研究所(Swiss Federal Institute for Forest,  相似文献   

11.
Estimates of the number of undiscovered deposits on a statewide basis offer a different perspective on the nation's undiscovered resources of gold, silver, copper, lead, and zinc. Mean estimates of the number of undiscovered deposits statewide were extracted from the estimates of undiscovered deposits nationwide. More than 50 undiscovered deposits are estimated to occur in Alaska, Arizona, Nevada, and Wisconsin. Estimating the number of undiscovered deposits statewide serves as a measure of a state's total remaining mineral resources in known conventional deposit types.  相似文献   

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Sediment Facies of a Low-Energy, Meso-Tidal, Fringing Reef, Singapore   总被引:1,自引:0,他引:1  
Pulau (P.) Semakau comprises a narrow, low-lying island, surrounded by a wide fringing coral reef of late-Holocene age. The modern reef flat comprises a gently sloping surface related to modern mean low water neap tide level. Six sediment facies are recognised below the line of high water of which three, adjacent to the island, are composed of terrigenous minerals and rock fragments and three are autochthonous carbonates sediments developed since local sea-level still stand (c. 6,500 years BP). The fringing reefs of P. Semakau and Singapore differ from many of the reef forms recorded from Peninsular Malaysia waters and the Gulf of Thailand. The Singapore reefs have wide, well-developed intertidal reef flats, lack lagoons and reef crests, and have a very steep reef slope. In contrast to most other fringing reefs of the region, the Singapore reefs have developed in a low wave energy, meso-tidal environment lacking strong environmental gradients.  相似文献   

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Estimates of the number of undiscovered deposits offer a unique perspective on the nation's undiscovered mineral resources. As part of the 1998 assessment of undiscovered deposits of gold, silver, copper, lead, and zinc, estimates of the number of deposits were made for 305 of the 447 permissive tracts delineated in 19 assessment regions of the country. By aggregating number of undiscovered deposits by deposit type and by assessment region, a picture of the nation's undiscovered resources has emerged. For the nation as a whole, the mean estimate for the number of undiscovered deposits is 950. There is a 90% chance there are at least 747 undiscovered deposits and a 10% chance there are as many as 1,160 undiscovered deposits. For Alaska, the mean estimate for the number of undiscovered deposits is 281. There is a 90% chance there are at least 168 undiscovered deposits and a 10% chance there are as many as 402 undiscovered deposits. Assuming that the majority of deposits used to create the grade and tonnage models that formed the basis for estimating the number of undiscovered deposits are significant deposits, there remain about as many undiscovered deposits as have already been discovered. Consideration of the number of undiscovered deposits as part of national assessments carried out on a recurring basis serves as a leading indicator of the nation's total mineral resources.  相似文献   

17.
A field study to examine the statistical character of dune morphology and the correlation among dune morphology, discharge, and flow resistance was conducted in a meandering reach of Lillooet River, near Pemberton, British Columbia, Canada. The field season spanned the 1995/1996 hydrologic year with sample day discharge events ranging between 33 and 425 m3 s−1. Surveys of the bed morphology along the thalweg in two dune fields (A and B) were completed using an echo sounder with chart recorder that enabled the measurement of more than 4000 dunes. Dune height ranged between 0.08 and 0.96 m, length between 2.01 and 20.99 m, and steepness between 0.02 and 0.10. Histograms of each dune shape (height, length, steepness) sample most often displayed positive skewness and non-Gaussian distributions (Gamma, Beta, and Weibull); median sample height and length histograms displayed positive skewness; and steepness was nearly Gaussian. Histograms of all dimensionless dunes (i.e., measurement divided by average measurement of sample) were Gaussian and slightly leptokurtic. Neither the height nor length of dunes measured in this investigation were successfully predicted by the empirical models of Allen [Allen, J.R.L., 1984. Developments in Sedimentology. Sedimentary Structures: Their Character and Physical Basis, 2nd edn. Elsevier, New York, vol. 30 (A and B), 1256 pp.], Fredsøe [J. Hydraul. Div., Am. Soc. Civ. Eng. 108(HY8) (1982) 932.], or Yalin [J. Hydraul. Div., Am. Soc. Civ. Eng. 90(HY5) (1964) 105.]. Least-squares regression models for dune–height relations produced here are similar to models published by other field researchers; regression models for dune length only conform to those developed elsewhere if the discharge of the study rivers was similar. The energy gradient in dune field A varied within a smaller range than in field B, enabling dune size to become more fully equilibrated with respect to flow environment. Although the average Froude numbers were much less than critical, dunes appeared to wash out towards a plane bed as discharge increased due to a change from a bedload to suspended-load dominated sediment-transport regime. Flow resistance increased most rapidly during changes in base flow and at the beginning and end of the seasonal flood; resistance tended to be smaller in field A than B, reflecting local differences in energy gradient. Flow resistance increased until a dune steepness of 0.070 was attained and then decreased. The steepness value was considered to be coincident with kolk generation [Dyer, K.R., 1986. Coastal and Estuarine Sediment Dynamics. Wiley, NY, 342 pp.], suggesting that macroturbulent flow structures play an important role in defining the roughness of dunes on a channel bed.  相似文献   

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Open sections along Kongsfjodhallet, the north-western coast Kongsfjorden, Svalbard, exhibit marine and glacigenic sediments of Early to Late Plestocene age. Glaciatio, deglaciation and subsequent isostatic rebound caused the formation of three sedimentary successions (A, B and C) that comprise till grading upward into glaciomarine mud, followed by shell-bearing sand, and finally littoral sand and gravel. Six major lithostratigraphic units are recognized. Succession C comprises units 1 and 2, which were deposited during an Early Pleistocene glaciation, followed by deglaciation and subsequent beach progradation. Succession B is divisible into units 3 and 4 and reflects glaciation and eventual emergence as a result of isostatic response. The youngest succesion (A) comprises units 5 and 6, and reflects fiord glaciation followed by a regression during an Early Weichselian glaciation-deglaciation episode. Ice-free conditions may have prevailed untill the Late Weichselian, when a glaciation, confined to the fiord trough, covered parts of Kongsfjordhallet. Deglaciation and isostatic rebound are recorded by Holocene marine terraces up to ca 40 m a. s. l.
Marine and glacial events from Kongsfjordhallet are compared with stratigraphic evidence from adjacent regions and it is suggested that the Late Weichselian ice configuration was of a more restricted nature than proposed by previous authors. Glaciers. draining through the larger ford troughs reached the shelf break. while at the same time other parts of western Svalbard could have experienced restricted glaciation.  相似文献   

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