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1.
COASTAL PHENOMENA AND ISOSTATIC UPLIFT AROUND FILDES PENINSULA OF KING GEORGE ISLAND, SOUTH SHETLAND ISLANDS, ANTARCTICA 
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下载免费PDF全文 《极地研究》1992,3(2):45-55
After a field work on recently raised coastal features in South Shetland Islands, we conclude that there are three kinds of recent coastal features, i. e, fragmental coast, rock coast, and ice cliff coast. The processes and forms of the fragmental cost formed by wave action with floating ice are studied. Systermtic study of the raised coasts enables us to distinguish two groups of the coasts by an elevation of 20m a. s. l. The raised coasts above 20m a. s. l. belong to older group and those below 20m a. s. l. belong to younger group. Mean uplift rate of coast in this area is 6.7 mm/a. 相似文献
2.
Permafrost in Svalbard: a review of research history, climatic background and engineering challenges 总被引：3，自引：0，他引：3
This paper reviews permafrost in High Arctic Svalbard, including past and current research, climatic background, how permafrost is affected by climatic change, typical permafrost landforms and how changes in Svalbard permafrost may impact natural and human systems. Information on active layer dynamics, permafrost and ground ice characteristics and selected periglacial features is summarized from the recent literature and from unpublished data by the authors. Permafrost thickness ranges from less than 100 m near the coasts to more than 500 m in the highlands. Ground ice is present as rock glaciers, as ice-cored moraines, buried glacial ice, and in pingos and ice wedges in major valleys. Engineering problems of thaw-settlement and frost-heave are described, and the implications for road design and construction in Svalbard permafrost areas are discussed. 相似文献
3.
Patrick D. Nunn 《The Australian geographer》2000,31(1):21-39
The islands Ovalau and Moturiki in central Fiji are selected for the investigation of coastal change over the past c. 200 years. Although having coastal environments typical of many tropical Pacific Islands, Ovalau and Moturiki are also atypical because they experienced urban and infrastructural developments before most other parts. The associated records enable recent coastal changes to be discerned more clearly here than has been possible elsewhere. The islands are surrounded by coral reef, the configuration of which accounts for variations in vulnerability of their coasts to erosion. Interviews were conducted in each of 22 settlements along the islands' coasts and information obtained about recent coastal change. Mangroves are concentrated along leeward coasts, although they have been cleared from many windward coasts in the last 40 + years, causing shoreline erosion to be initiated/accelerated. Most shoreline-protection initiatives (vegetation planting and seawall construction) have failed. Three major management implications of the study are discussed. Firstly, there is a need to redefine the nature of the interactions between coastal inhabitants and coastal ecosystems, so that environments are sustainably developed; and specifically that reefs are conserved and shoreline vegetation (especially mangroves) is effectively replanted. Secondly, information about appropriate design and composition of artificial structures for shoreline protection needs to be made available to the local communities who construct most of them. Thirdly, alternative sources of sand and rock aggregate to those whose extraction aggravates shoreline erosion should be sought. 相似文献
4.
Coastal dune rocks in China are eolian sands cemented by calcium carbonate under subaerial conditions,widely distributing on the tropical and subtropical coasts of South China.Particular temperature and precipitation as well as local wave and landform conditions are required for the formation of the dune rocks.A correspondence was found between Holocene environmental changes and coastal dune rock development by comparing the features of the sea-level and climate changes in the Holocene period with the ages,... 相似文献
5.
华南海岸沙丘岩形成与全新世环境变化的关系 总被引：3，自引：0，他引：3
海岸沙丘岩是热带亚热带地区由碳酸盐胶结的海岸风成堆积,其成岩过程的各个阶段需要特定的水热和地貌条件。对华南海岸沙丘岩的形成年代、堆积高度、出露地点进行统计分析,将其特征与全新世环境变化事件作对比, 结果显示华南沿海沙丘岩的形成过程与全新世气候变化及海平面变化等事件有很好的对应关系, 能很好地解释我国沙丘岩研究中一些尚未解决的问题：华南沿海缺少5000a BP以前沙丘岩是因为当时的沙丘岩形成于低海面,后来因海面上升而被淹没;3000a BP前后海岸风沙大规模堆积是大暖期结束后气温下降的结果;华南沿海沙丘岩的胶结主要发生在中世纪暖期;华南沿海缺少年代小于1000aBP沙丘岩是因为近千年来气候条件下,不适合沙丘岩的胶结。 相似文献
6.
Coastal dune rocks in China are eolian sands cemented by calcium carbonate under subaerial conditions, widely distributing on the tropical and subtropical coasts of South China. Particular temperature and precipitation as well as local wave and landform conditions are required for the formation of the dune rocks. A correspondence was found between Holocene environmental changes and coastal dune rock development by comparing the features of the sea-level and climate changes in the Holocene period with the ages, scales, and cementation of the dune rocks on the South China coasts. The findings provide well grounded explanation for some problems unresolved in the past researches on the coastal dune rock in South China: (1) There were no dune rocks with ages older than 6000 years in South China because the dune rocks formed before 6000 a BP were covered by the sea water that rose in the later period; (2) the dune rocks with ages of around 3000 a BP were widely found in South China today because the coastal dunes were cumulated on a large scale at that time as a result of temperature falling after the end of Megathermal; (3) Medieval Warm Period was the main period for the eolian dunes to be cemented into the coastal dune rocks in South China; (4) lack of dune rocks of younger than 1000 a BP was accounted for by that the climate conditions in recent one thousand years were not suitable for the cementation. 相似文献
7.
海平面上升对长江三角洲和苏北滨海平原海岸侵蚀的可能影响 总被引：33，自引：5，他引：33
本区海岸现有30％的岸段为侵蚀海岸,海平面上升将使海岸侵蚀加剧。海平面上升因素在海岸侵蚀诸因素中的比重较国外同类研究结论偏小,这与本区海岸的特殊演变原因有关。海平面上升通过潮流、波浪和风暴潮作用增强,海岸潮滩和湿地损失,岸滩消浪和抗冲能力减小等途径引起海岸侵蚀加剧。其结果是,侵蚀岸段扩大,淤涨岸段减少甚至转为侵蚀,潮间带宽度变窄,坡度加大,从而使沿岸海堤等挡潮工程的标准要相应提高。 相似文献
8.
ABBIE TINGSTAD 《Geografiska Annaler: Series A, Physical Geography》2008,90(2):165-171
A fundamental concern in the practice of experimental research is how to ensure that laboratory simulations model field conditions as closely as possible, thereby providing useful information about natural and built environments. Salt weathering is one research area where studies conducted in the laboratory have fostered a significant portion of the knowledge, but the results of many experiments are difficult to apply to field sites because they focus on the salt weathering process itself, rather than the situation at a particular site. The design of the experiment reported in this paper, which simulates salt weathering along a hard-rock coast near Swansea, Wales, incorporates the results of previous work that demonstrated the critical importance of the salt solution, rock properties, and environmental conditions in determining the rate and nature of salt weathering. SEM images demonstrate the development of incipient weathering zones with characteristics specific to the type of salt solution used, a result that may have implications for the origins of larger-scale weathering features. Samples also gained mass due to the uptake of salt. This work is useful both for understanding a process that helps to shape hard-rock coasts, and in highlighting the importance of experimental design in salt-weathering research. 相似文献
9.
Peter Kamstra Brian Cook David M. Kennedy Chris Brennan-Horley 《The Professional geographer》2013,65(3):491-506
This article presents an innovative mixed methodology that integrates qualitative geographic information systes (GIS) methods to expand the examination of space in the context of people’s lived experiences and risk. We emphasize the specific ways in which individuals perceive risk by treating risk as relational. Conceptualizing risk as relational challenges traditional assumptions of risk by rejecting that risk is the combination of physical and social elements. Instead, a relational understanding explores the socioenvironmental interactions that are perceived as hazardous, as they emerge in space. Such claims have long animated risk research, but only recently have methodological advances opened opportunities for relational analyses. Using hazardous coasts as the case, we analyze rock fishers’ risk perceptions and whether those perceptions influence their movement. Analytically, we relate rock fishers’ Global Positioning System movement with participant observations, video, semistructured interviews, and sketch maps anchored to questions focusing on spatial understandings of risk. In doing so, fishers’ perceptions of socioenvironmental stimuli are spatially represented, with sketch mapping as a window into the perception–environment interactions that produce risk. This methodology opens new possibilities for understanding human–environment systems that typically overlook how, where, and for how long risky human–environment interactions are perceived in space, if at all. Key Words: qualitative GIS, relational, risk, risk perception, space. 相似文献
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11.
大鹏半岛位于广东省深圳市东部,海岸地貌类型多样,可分为基岩海岸、堆积海岸和生物海岸3大类型。文章根据野外调查和室内实验分析的结果论述了大鹏半岛海岸地貌类型、分布和成因,并在前人的研究基础上讨论了大鹏半岛海岸地貌演化过程：由于大鹏半岛处在构造隆升区,海岸类型以基岩海岸为主。多处基岩海岸保留了完好的海蚀崖、海蚀平台、海蚀槽穴、海蚀柱等各类典型的海蚀地貌。该半岛的堆积海岸主要发育于岩石岬角间的海湾内,在有河流流入的海湾处形成岬湾沙坝―澙湖海岸,在无河流的海岸处则形成湾顶海滩。半岛中段狭窄的呈哑铃状腰部的东岸,因深入内凹、波浪减弱,有淤泥质海岸发育;红树林发育于淤泥质海岸以及各澙湖内,而半岛周边浅海区有珊瑚群落生长。大鹏半岛以及邻近地区海岸地貌特征和海岸沉积物年代数据显示：1）地质构造与海平面升降是塑造该半岛海岸地貌的主要因素;2）该半岛的海岸地貌是在中全新世早期以后才开始发育的;3）该半岛全新世以来不存在强烈的地壳抬升;4）该半岛海岸中全新世出现过高于现代海平面的高海面。 相似文献
12.
Rock varnish has a long history of study in Australia. Although Australian varnishes have biological, chemical and morphological similarities to varnishes in other continents, rock varnishes in arid Australia tend to be less stable than in other drylands. Still, with careful sampling, radiocarbon and cation‐ratio dating of rock varnish has been used to constrain the age of Henbury Meteor Craters, Northern Territory, and rock engravings in South Australia and New South Wales, as well as to assess the geomorphic surface stability of Ayers Rock, Northern Territory, and the slopes of Pepuarta Bluff in the Olary Province of South Australia. 相似文献
13.
In this paper, we look at the relationship between the development of domestic and overseas markets for Australian renewable energy. It is argued that encouraging the promotion of Australian renewable energy technology in overseas markets could be a practical strategy for developing the Australian renewable energy industry. Also, it is reasoned, Australian foreign aid and trade organisations could play an important role in assisting the Australian renewable energy industry via overseas market research, technology transfer, and human resource and institutional development programs. We suggest that further research and development cooperation between Australian renewable energy companies and research institutes would be beneficial, especially in exploring potential overseas markets. We also recommend that joint ventures between renewable energy industry partners in Australia and developing countries be used to promote growth in Australian renewable energy exports and, ultimately, in developing Australia's renewable energy industries. 相似文献
14.
中国海岸风沙沉积的成因与特征 总被引：11，自引：4，他引：7
东部和南部沿海是我国风景优美、气候宜人, 工农业与交通事业发达和人口密集的重要经济区。在16, 000多公里的海岸上, 风沙作用的海岸线就有近3, 000公里, 目前它们都在不同程度上处于风沙作用而后退或大大改观的状态。 相似文献
15.
This paper describes the morphology of near-horizontal basalt and calcarenite shore platforms around Lord Howe Island as well as the lithological and process environment in which they occur. The morphology of platforms around the island is highly varied. For instance, they occur at a wide range of elevations between low-tide level and several metres above the highest tides, and their width ranges between just a few metres to over 100 m. However, common to most platforms is that they have near-horizontal surfaces that terminate abruptly in a steep scarp at their seaward edge. Correlations indicate that the variability in platform elevation and width is attributable to variability in key parameters of erosion, such as rock resistance and shoreline water depth. Whereas wider platforms occur in rocks of lesser resistance, platform elevation is shown to increase both as rock resistance and the depth of water at the shoreline increases. Wave exposure has a significant control on platform width in some instances, but an over-arching relationship was not detected. Most platforms around the island appear to have developed over the Holocene and a conceptual model is proposed to account for the varied morphology of platforms that have developed over this period. Resistant plunging cliffs occur along about 18% of the rocky coastline of Lord Howe Island and represent the starting point for the model. Where cliffs have yielded to wave erosion platforms have been initiated at an elevation controlled predominantly by rock resistance and shoreline water depth. At Lord Howe Island narrow platforms up to about 20 m wide in exposed locations generally occur about 4 to 6 m above high tide level, and have apparently been subject to very infrequent erosion. Shore platforms about 20 to 40 m wide have generally formed in less resistant rocks, are somewhat lower at about 2 to 3 m above high tide level, and have been subject to more frequent erosion over the Holocene. Most basalt platforms around the island fall within these first two categories, but there are some instances of platforms about 50 m wide. These platforms have formed in rocks of comparatively low resistance and are relatively low in elevation occurring close to the level of high tide. An interesting feature of some of these wide platforms is that, unlike the morphology of narrower platforms, raised ramparts sometimes occur on their outer edge. 相似文献
16.
沙丘风蚀坑的形态及动力过程的研究进展 总被引：12，自引：3，他引：9
随着风沙活动对全球变化的响应研究不断深入,沙质海岸、湖岸和半干旱区草原环境中不同程度植被覆盖沙丘及其风蚀坑的动态得到了广泛的重视。本文对沙丘风蚀坑的形态及动力学特征的研究成果作了初步总结,着重阐述了沙丘风蚀坑内气流场、沙粒输移和蚀积变化。最后,提出了沙丘风蚀坑研究巾存在的问题和主要研究趋势。 相似文献
17.
广东沿海赤潮发生与城市发展的关系 总被引：2，自引：0，他引：2
Red tides are one of the main coastal catastrophic events in Guangdong Province of southern China. The comparison between the number of red tide events and the development indexes of cities along the coasts of the province shows that the regional differences in red tide outbreaks has close relations with the coastal urban developments. The cause for an initiation of red tide blooms may be natural factors, while wastewater caused by the fast development of population, industry and aquiculture of the coastal cities enhanced the blooms. It may explain why the two periods of frequent outbreaks of the red tides over the last two decades matched the urban developments in the coastal areas of Guangdong not only spatially but also temporally. The red tides in the first period were restricted only to the coasts of middle Guangdong, where urbanization process was at a higher speed than the other coastal areas of the province. In the second period, fast development of the coastal cities in eastern Guangdong led to an increase in the occurrence of red tides in local sea areas of the same coasts. 相似文献
18.
将广东沿海划分成粤东、珠江口和粤西3个区域,采用每个区域主要城市有关经济指标与广东沿海1980~2002年赤潮发生频率的统计数据进行对比分析。研究结果表明：22年间广东沿海出现了2次赤潮高峰期,分别为1987~1992年和1998~2000年;珠江口海域为珠江水系入海口集中区域,广东陆源污染物集中于此出海,是赤潮发生的敏感区域。随城市的发展,陆源污染物进入海洋的数量加大,临近城市化发展较快的珠江口海域赤潮出现的频率高于其他城市化相对较慢的海域,同时沿海城市经济快速发展的时期也是赤潮出现的高峰期。 相似文献
19.
Red tides are one of the main coastal catastrophic events in Guangdong Province of southern China. The comparison between the number of red tide events and the development indexes of cities along the coasts of the province shows that the regional differences in red tide outbreaks has close relations with the coastal urban developments. The cause for an initiation of red tide blooms may be natural factors, while wastewater caused by the fast development of population, industry and aquiculture of the coastal cities enhanced the blooms. It may explain why the two periods of frequent outbreaks of the red tides over the last two decades matched the urban developments in the coastal areas of Guangdong not only spatially but also temporally. The red tides in the first period were restricted only to the coasts of middle Guangdong, where urbanization process was at a higher speed than the other coastal areas of the province. In the second period, fast development of the coastal cities in eastern Guangdong led to an increase in the occurrence of red tides in local sea areas of the same coasts. 相似文献
20.
运用定量指标研究岩体风化问题的探讨 总被引：7，自引：0，他引：7
在分析国内外岩体风化问题研究现状的问题上，指出了目前岩体风化评价存在的主要问题。结合实际工程资料，从影响岩体风化的主要因素出发，选择了表征风化特征的代表性定量指标，并分析了指标间的相关性。这为风化岩体的量化评价提供了依据。 相似文献