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岩石风化是地貌学研究的重要内容，但对其机制的研究也可应用于建筑物风化及其抗蚀性的领域，本文从岩石风化研究的角度出发，参考了大量建筑物风化研究的有关文献，认为建筑物风化研究的思想和实践对地貌学的风化理论研究有重要的借鉴意义，同时认为，在环境污染日益严重的今天，岩石风化研究不应该仅仅局限于地貌学理论与地貌演化领域，也应涉及建筑物风化研究的应用领域。 相似文献
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试论地貌学的新进展和趋势 总被引：1，自引：0，他引：1
地貌变化有内在的规律,对环境保育、资源利用和自然灾害防治有重要影响。作为交叉学科和地理学的重要分支学科,地貌学具有重要理论价值和实际意义。过去10多年来,随着遥感、地理信息技术和沉积物定年、地球物理和地球化学探测以及数值模拟等新技术和新方法的应用,地貌学家的研究视野和深度不断扩大与加深,在构造地貌、气候地貌和人类活动与地貌过程等传统领域有很多新进展,揭示了不同地貌单元的变化规律和机理,极大地推动了地貌学的发展。在新时代,除了继续加强传统地貌单元的深入研究外,地貌学的发展应与全球环境变化和未来地球等重大科学问题(计划)紧密结合;地貌学家要关心人类活动对地貌过程的影响及适应,并利用新技术开展地貌过程的定量重建和数值模拟。同时加强地理学专业学生的地质学基础学习、发展定量地貌学和行星地貌学、系统开展人类活动对地貌过程的影响和适应研究,是提升中国地貌学水平的途径,也可为推动国际地貌学发展做出贡献。 相似文献
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风化洞穴在全球不同气候区广泛发育,其形成过程和主控因素是地貌学研究的热点问题,但形成机制至今仍存在不少争议,尤其对丹霞地貌区风化洞穴的研究还较少。丹霞山是世界自然遗产地“中国丹霞”的典型代表,陡坡上发育形态和规模各异的风化洞穴,是丹霞地貌的重要景观要素,为认识亚热带湿润气候风化洞穴成因提供了良好的机会。文章以丹霞山砾岩和砂岩陡坡上的5处典型风化洞穴为研究对象,利用野外考察、形态测量、气象监测、样品显微观察及盐化学实验等方法,在已有研究的基础上进一步对湿润气候丹霞地貌区风化洞穴的特征和成因进行探讨。结果表明：1）在砾岩中发育的洞穴一般个体形态较大,洞穴具有较明显的向上和向内生长趋势;砂岩中发育的洞穴大多密集排列,形态较小,常具有蜂巢结构。2）岩石性质是洞穴发育的基本影响因素,在宏观尺度上决定了洞穴的发育位置和排列方式,也决定了不同岩性下发育的风化洞穴的形态特征。在微观尺度上,岩石含有较多长石、钙质胶结物等易溶矿物组分,在酸性雨水渗流过程中发生化学溶解,加上盐结晶作用导致岩石微观结构破坏,诱发洞穴初始形成。3）洞穴尺寸变大后,洞穴内适宜的微气候是洞穴演化的关键因素,为水和盐的聚集及盐风化提... 相似文献
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福建长乐屏山风化坑与河流壶穴的成因及其证据 总被引：1，自引：0，他引：1
风化坑和壶穴是一种常见的岩石坑穴地形,其形成原因和形态完全不同,但容易被误解和混淆.结合对福建长乐三溪河地区这两种坑穴地形的实地考察,本文从地貌学,沉积学,岩石化学和矿物学等各个方面对两者的形成过程、影响因素进行了论证和对比.研究表明：风化坑形成于岩石面积水的风化作用,壶穴则是由河流的旋转水流对河床产生的侵蚀作用形成;山顶风化坑的发育与河流流水作用没有关系,河流壶穴的形成与河谷的发育过程有关,河谷中的风化坑只能在河流深切后,流水不再作用到的河床部位发育;只要条件合适,风化坑或壶穴随时可以生成;风化坑与河流壶穴的形态,坑内沉积物的磨圆度、粒度特征等反映出各自不同的形成过程.风化坑内碎屑与周边岩石的化学蚀变指数CIA 值的差异反映了风化坑的化学风化成因;风化坑内碎屑与周边岩石石英长石比例的差异说明风化坑是矿物差异风化的结果;用CIA 值和英长比均无法区分河流壶穴和风化坑中的碎屑颗粒,但两者化学元素迁移特征的差别反映了风化坑的风化作用和河流壶穴的流水搬运作用的成因差别;风化坑的风化程度达不到当地风化壳的风化程度,但不同气候带风化坑碎屑的CIA 值能反映不同气候带风化作用的强度差异. 相似文献
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盐风化是干旱区一种重要的岩石风化过程。本文初步研究了盐风化作用的性质、机制和强度及其在地貌塑造和生产实践上的意义。盐风化包括盐结晶风化作用和盐水化风化作用两种类型。盐风化的强度在很大程度上取决于盐类矿物性质和气候条件。高温和干旱相结合的气候最有利于盐风化过程。通过对未风化岩石和风化岩石的对比,证明盐风化发展的速率很高。Tafoni是盐风化发展阶段的一种重要标志。 相似文献
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中国近40年来地貌学研究的回顾与展望 总被引：5，自引：2，他引：3
地貌学是地理学的一门主要分支学科,其研究成就与发展一直倍受人们关注。本文对中国近60年来的研究状况,尤其近40年来研究历程进行了回顾,从总结经验与发展态势出发,对地貌学科未来发展方向提出了展望。分析认为,中国地貌学科在地貌基本类型、区划以及分支学科：包括动力地貌学（包括冰川地貌、冰缘地貌、风沙地貌、黄土地貌、喀斯特地貌、河流地貌、海岸地貌等）、构造地貌学、气候地貌学、古地貌、岩石地貌学（包括丹霞地貌、花岗岩与流纹岩地貌）、其他地貌类型（包括重力地貌,人工地貌）等方面取得重大进展,地貌学已逐渐发展成为一门拥有完整学科体系的科学。通过回顾认为,应坚持地貌成因、形态相统一的原则发展传统地貌与综合地貌。加强地貌基础理论与综合地貌研究、开展地貌结构及其功能研究、构建全方位资源环境地貌信息系统、加强海岸地貌与海洋地貌研究、加强人才培养和学术团队建设,将是中国实现地貌强国目标的主要途径。 相似文献
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最近 Müucher 和 Morozova(1983)回顾了土壤薄片研究在地貌学中的作用,并指出了同土壤学、考古学和古土壤学研究的交叉。按严格的地貌学意义来说,薄片是用于侵蚀和沉积两个过程的研究。研究的主要过程之一是在不同的侵蚀处产生粗物质的残留聚集。这在热带、亚热带地区地表已受到化学风化和数百万年的逐渐剥蚀的地方尤其普遍而重要。 相似文献
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Heather Viles 《Geomorphology》1995,13(1-4)
A wide range of information is now available on the ecology of rock surface microorganisms (including bacteria, fungi and algae) and lichens and their role in weathering in particular locations. External environmental conditions as well as rock characteristics determine the type of rock surface community, and thus the style of biological weathering. A simple, preliminary conceptual model can be drawn, which relates biological weathering activity to an environmental stress gradient and which is applicable at a range of scales. Further research needs carrying out to test and extend this model in order to make some progress towards the important goal of assessing the overall importance of biological weathering to geomorphology. 相似文献
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以柴达木盆地西南缘山前沙丘区为研究区,采用地球化学元素分析方法,阐明了研究区不同类型地表沉积物的地球化学元素特征,并探讨其风化特征、物质来源及输移过程。结果表明：(1)研究区沉积物常量元素组成以SiO2、Al2O3和CaO为主,三者的平均含量总和超过83%。微量元素以Cl、Ba、Sr和Zr含量较高。与上陆壳(UCC)平均化学元素组成相比,常量元素CaO轻微富集,微量元素As高度富集,Co轻微富集。(2)研究区化学蚀变指数(CIA)变化较小,为40.90～53.05,平均47.51,化学风化程度较弱,均处于风化的初期阶段。(3)特征元素比值表明,研究区沉积物具有相同的物质来源。柴达木盆地西南缘东昆仑山中的岩石经过风化剥蚀产生的碎屑物质在季节性流水作用下被搬运至山前堆积,形成广布的山前冲-洪积平原,后经风力吹蚀改造形成现在的地表景观。本研究不仅可以丰富区域风沙地貌研究内容,而且也可为区域风沙灾害的防治提供理论基础。 相似文献
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Dust sources in arid and semiarid China and southern Mongolia: Impacts of geomorphological setting and surface materials 总被引：1，自引：0，他引：1
Analysis of the geomorphological settings and surface materials in arid and semiarid China and southern Mongolia revealed that the dominant dust sources are ‘Gobi’ deserts and alluvial fans adjacent to Gobi deserts in the piedmonts of the Kunlun, Qilian, Helan, and Gobi Altai mountains. These areas have persistent supplies of dust-sized particles, deposited by intermittent floods from the mountains, and fine materials are also generated by weathering and aeolian processes acting on the coarse fractions of Gobi surfaces. Clear spatial differences in mineral types and contents and in the salt contents of surface materials also strongly affected the intensity of dust emissions. Inconsistencies in monitoring, simulation, and calculation of dust emissions in previous studies of Northern China and Mongolia may have been caused by insufficiently detailed considerations of variations in the geomorphological setting. Where the geomorphological settings in these areas are not considered in sufficient detail, deviations arise in the estimation and prediction of dust using current models. Although the present study did not quantify the persistence and replenishment of dust sources in the study area, our conclusions about the importance of geomorphology can improve future studies of dust sources and controlling factors, improve assessments of the effects of climate change on dust emissions, and facilitate the interpretation of paleoclimate records. 相似文献
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随着人类改造自然能力的增长,人类与环境地貌之间的相互作用加剧,地球表层的地貌系统在自然地域分异的基础上,出现的新的内容和特征。地貌演化不再是纯自然的过程,而且,人工地貌、人工—自然混合地貌占的比重增加了。因此,有必要对人、环境与地貌的作用机制,地貌的环境意义等问题进行研究,于是,环境地貌学应运而生。与传统地貌学不同的是,环境地貌学从人类活动与环境地貌相互作用的角度,运用系统论、综合分析方法,厚今薄古,研究现存地貌特征及后效,做出环境地貌的经济评价,探讨环境地貌的社会文化效应。本文拟对环境地貌学的产生、学科性质、研究内容和方法进行探讨,希望有助于促进环境地貌学的研究。 相似文献
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Relationships between landscape-scale geomorphology and aspects of the human environment (including heritage and material cultures) are best examined in landscapes with a strong geomorphological imprint of past climatic and environmental changes, and where human activity has been present for a long period of time. In Cornwall, southwest England, a strong geomorphological signature is imparted by weathering of granite bedrock under cold Quaternary climates, and a strong cultural and heritage imprint is manifested in material and nonmaterial ways through archaeology, art, literature and folklore, and is illustrated in this paper through examples of Bodmin Moor (north Cornwall) and West Penwith (west Cornwall). Landscapes of Bodmin Moor include wide valleys with underfit rivers and upland summits with prominent tors, resulting from granite weathering and slope processes during the Tertiary and Quaternary. Pollen records show how human activity has changed on the moor over time, with a peak of settlement during the Bronze Age, and expansion of grazing into the Iron Age. Daphne du Maurier's novels, set on or adjacent to Bodmin Moor, emphasize the moor's relationship to unstable and intense human emotions and crises. In West Penwith, which is geomorphological similar to Bodmin Moor, geomorphology–culture relations are demonstrated in different ways but through a similar sense of place and regional identity. The St Ives School of early 20th Century art, including the local artist Peter Lanyon and the sculptor Barbara Hepworth, draws inspiration from the local land and seascapes. The oral traditions and folklore of Zennor emphasize the importance of witchcraft and superstition that are in part founded on the wildness of upland summits and stormy coastline. Across West Penwith, tin mining and the mining trade exerted a strong impact on regional socioeconomic and cultural development from the Bronze Age until the end of the 19th Century, seen through settlement patterns, scientific innovation and Nonconformism. Today these geomorphology–culture relations are memorialized in the Cornwall and West Devon Mining Landscape World Heritage Site. 相似文献
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R.W. Young 《The Australian geographer》1997,28(1):89-96
G.H. Dury was one of the outstanding figures in postwar geography and geomorphology. Although known chiefly for his research into the impact of climatic change on streams, he made important contributions to the study of pediments, of deep‐weathering, and of climatic extremes and fluctuations. He also did innovative work in historical and regional geography, and contributed greatly to geographical education in both universities and high schools. Dury played a central role in the transformation of the discipline and continued to challenge it after his retirement. 相似文献
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Chemical weathering studies in relation to geomorphological research in southeastern Canada 总被引：1，自引：0，他引：1
Although chemical weathering provides fundamental information relevant to geomorphology, the subject has been overlooked during the 20th century in Canada. This paper provides an overview of the current state of Canadian research on chemical weathering in southeastern Canada and takes into account three spatial and temporal contexts: (1) the formation of bedrock morphology by chemical weathering, (2) occurrences, characteristics and age of saprolites and (3) contemporary chemical denudation rates. Long-term geomorphological evolution of southeastern Canadian landscapes shows that chemical weathering has played an important role. An example is taken from the Laurentide region of the Canadian Shield north of Montréal (Québec). The present topography resulted from the stripping of the former weathering mantle and from the probable subsequent modification of the weathering front, first by the action of hillslope processes and rivers and then by glaciers, before and during Plio-Pleistocene times. The present landscape reflects the timing of the formation of erosion surfaces, and of the stripping of the Paleozoic cover rocks and exposure of the Shield. Since the late seventies, several isolated occurrences of saprolite-soil profiles have been discovered in eastern Canada and prompted a renewal of the study of these materials about the Cenozoic evolution of these regions. One of the problems in this field of research is the dating of saprolites and their inclusion in a chronostratigraphic framework, along with the other Cenozoic surficial deposits and landforms. Because of the multiple factors involved in the development of secondary minerals in saprolites during the course of weathering, it is preferable to distinguish the dating of saprolites from the study of their mineralogical and geochemical evolution. Fortunately, several new techniques are becoming available for the absolute dating of surficial deposits and saprolites, including the use of cosmogenic radionuclides. Saprolites provide a strong potential field of research for our understanding of the geological evolution of eastern Canada during the Cenozoic. Contemporary weathering and erosion rates are fields of research that have gained increasing interest recently, since modeling landscape geochemical response can be applied to various environmental stress situations, such as acidification by rain and forest harvesting. Rock-type may be the main factor explaining the large differences between watersheds. In fact, variability of cation removal in the temperate zone is probably most closely related to flow-paths of water. Investigations, at different scales, from entire watersheds to slopes to individual pedons, highlight the problem. In the Catamaran Brook watershed (New Brunswick), water chemistry is explained by a mix of groundwater and soil solution from the horizons at the base of the floodplain soils. Geochemical mass-balances based on net outputs give little information on the weathering reactions of primary minerals, the weathering products or on the nature of the weathering processes that provide the dissolved load of streams. Mineralogic and petrographic analysis of selected soil pedons are necessary to determine weathering reactions and their role as sources or sinks for bases, silica, aluminum and iron in the various compartments through which water percolates before it reaches the stream. 相似文献