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The Minister of Geology USSR recommends that geomorphology play a more significant role in prospecting and exploration of mineral deposits. He finds that many Soviet exploration geologists still tend to ignore the potentialities of geomorphology on the ground that it is a geographical discipline with little relevance to the needs of geology. The Minister sees a particularly important area of applied contributions in paleogeomorphology, which deals with the relief forms of past geological eras. In his view, geomorphology also has a major role to perform in engineering designs of major construction and development projects. Failure to select proper project sites often leads to undesirable side-effects, especially in areas affected by mudflows, avalanches and thermokarst caving. If geomorphology is to make a more substantial contribution in areas of application, the training of geomorphologists should be reoriented toward mineral prospecting and engineering applications, and the organizational structure of operating and research agencies must provide for separate geomorphology study units.  相似文献   

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Mount Augustus (Burringurrah) at 1105 m AHD, is a prominent elongate inselberg, underlain dominantly by resistant sandstone of Middle Proterozoic age (1.6 billion years old). It is located midway between Meekatharra and Carnarvon in semi-arid Western Australia. The Mount Augustus Sandstone and overlying sediments were folded and tilted about 1 billion years ago, providing the template for the modern Mount Augustus. It is essentially a structural landform. Its shape broadly conforms to the underlying asymmetrical anticline, which has a steep northern limb and a gentler dipping southern limb. The anticline plunges at a shallow angle to the southeast. The mountain is the core of the original fold and it stands some 700 m above the surrounding Gascoyne planation surface. Other rock types present on Mount Augustus include metamorphic and igneous rocks, which preclude it from being termed a monolith. Weathering, fluvial erosion and sedimentation have modified the original bedrock structures. Fluted bedrock provides evidence of rapid runoff from bare bedrock surfaces. A joint system has influenced the orientation of a step-like sequence of numerous scarplets on slopes. The weathered rock is red, but the coloured rock is only a centimetre deep on most surfaces. The surrounding alluvial, gibber and sand plains shallowly bury the eroded bedrock plains of the Gascoyne planation surface. Former alluvial fills have been ferricreted in the lower reaches of some channels and are currently being eroded. Mount Augustus has often been compared with Ayers Rock, and unwarranted claims have been made that it is the biggest rock in the world and the world's biggest monolith.  相似文献   

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Australian river landscapes offer many challenges for management. Much Australian river research is novel, but practical concerns have always had an influence on the research agenda. Australia’s distinctive contributions to fluvial geomorphology include recognition of the great age of many fluvially eroded landscapes; understanding complex levee, terrace and valley fill sequences; analysing the impacts of rare major floods; interpreting the effects of impoundment, mining and urbanisation; and understanding the great anastomosing inland river systems. River restoration is now a major theme in the literature of river engineering, fluvial geomorphology and landscape design. Great achievements are occurring in geo‐ecological river management and engineering. Changing people’s thinking is becoming at least as important as gaining new scientific knowledge. The existing understanding needs to be more widely shared and enhanced by greater involvement with Asian countries where river management issues daily affect the lives of millions of people.  相似文献   

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The chenier plain of southwestern Louisiana is described on the basis of the American literature and a personal visit. It is suggested that this is a distinctive type of accumulative coastland characterized by the alternation of marsh and beach ridges and formed by the pulsating influx of stream-borne and marine sediment and the alternating predominance of longshore and onshore transportation of sediment. The chenier plain of Louisiana is found to have analogs in the Guiana coast and in the Myzeqeja plain of Albania as well as in ancient, buried chenier deposits.  相似文献   

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吴耀利 《中原文物》2001,4(4):16-23
总观全国各地新石器时代文化的发展,中原地区以它强大的文化根基,在文明起源和形成过程中始终走在前面.中原地区文明的起源是相当早的,在龙山时代晚期,中原地区已进入文明时代.  相似文献   

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The countryside around towns is under increasing pressure for development as a result of the centrifugal forces which have characterised the capitalist urbanisation process in the post‐war era. Conflict between pro‐growth and anti‐growth interests is now endemic in many peri‐urban areas. This paper identifies the principal agents involved in the production of the built environment in the urban fringe and presents a detailed analysis of how divergent interests interact to determine the nature of the fringe environment. The research informs academic debate on rural land conversion and provides guidance for decision‐makers charged with management of the urban fringe.  相似文献   

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Since 1996, a broad range of publications has been produced by Canadian geomorphologists and hydrolo‐gists. These publications have been distributed in journals with national and international circulations. Although there remains a major focus on the study of observable processes in fluvial, aeolian, coastal and slope environments there is also a strong, historical component to explanations oflandforms, landform assemblages and sedimentary sequences. Some of these histories have incorporated the effects of high‐magnitude (catastrophic) events, some of which may have no modern analogues. Perspectives on the interactions among microclimatic variables, including changes induced by human actions, continue to evolve. Forest clearance and its effects on evaporation rates, water‐table levels and timing ofsnowmelt, the human use of wetlands and release of methane and carbon dioxide, will continue to demand the attention of scholars interested in explaining future climatic scenarios. Depuis 1996, un large éventail de publications a été produit par les géomorphologues et hydrologues du Canada. Ces travaux ont été diffusés dans des revues nationales et internationales. Bien qu'il y ait encore une attention privilégiée portée à l'étude des processus observables dans des environnements fluviaux, éoliens, côtiers et de pente, il existe aussi une importante composante historique dans l'explication des formes du paysage et de leurs assemblages ainsi que des séquences sédimentaires. Certaines de ces reconstitutions historiques ont incorporé les effets d'événements de haute magnitude (catastrophique), dont certains n'ont peut‐être pas d'analogues modernes. Les points de vue sur les interactions entre les variables microclimatiques, et notamment les changements d'origine anthropique, continuent d'évoluer. Le recul des forêts et ses effets sur les taux d'évaporation, le niveau des nappes phreatiques et le calendrier de la fonte des neiges, l'utilisation humaine des zones humides et l'émission de méthane et de gaz carbonique, continueront d'exiger l'attention des spécialistes qui se penchent sur l'explication des scénarios climatiques futurs.  相似文献   

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昆仑文化作为一个学术体系,是一个令人肃然起敬,一个令人心驰神往,一个令人回肠荡气的文化,她给中华民族带来了无法估量的深远影响。近年来,国内外专家学者有关昆仑文化学  相似文献   

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在仰韶文化分布的中原地区 ,是中国古代文明的发祥地。仰韶文化的发展阶段 ,已处于中国古代文明起源与形成时期。仰韶文化在中国古代文明的发展进程中 ,占有极为重要的地位  相似文献   

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The author discusses three specific areas in which he made personal observations: Lake Bonneville, Yellowstone National Park, and ancient soil formations near Washington, D. C., and reports the latest American findings on the paleogeography of these areas. He finds the teaching and applications of geomorphology in the United States to be at a lower stage than would appear from American Geography: Inventory and Prospect.  相似文献   

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Historical records indicate that the fertile soils of the western and central Wimmera Plains of Victoria, Australia formerly supported grassy woodlands on rises and flats, and grasslands on shallow depressions and clay plains. Soil type and micro-relief appear to have been the major factors that determined the distribution of these communities. Burning of the woodlands by Aborigines may have contributed to their open grassy nature. The few ungrazed remnants of Buloke (Allocasuarina luehmannii) woodland support a suite of species that are absent from or uncommon in other Buloke woodland remnants in the region. This work demonstrates that in districts where little intact native vegetation remains, investigation of the distribution and floristic composition of the pre-settlement vegetation can provide useful information for the maintenance and restoration of remnant vegetation.  相似文献   

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1977年7月,一份旨在宣传国家文物政策、反映全省文物工作动态、总结交流工作经验、普及文物知识的内部刊物──《河南文博通讯》,像一株幼苗,在古老的中原大地上破土而出。1981年,为了能够及时地发表考古发掘成果和学术论著,扩展学术研究的领域和地域范围,以大中原的概念,涵盖河南及其邻近地区的历史文化,经过充分的酝酿,《河南文博通讯》更名为《中原文物》,开始向国内外公开发行。 《中原文物》从创刊到现在已25年,出版已100期。20多年的历程,使我们深刻体会到,离开中原这个文物荟萃之地,失去蕴藏丰富的文…  相似文献   

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