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Hsi Hu, the Western Lake of Hanchow, has been famous as summer resort and playing ground since the Tang and Sung Dynasties. During the time of Han, however, it was called Ming Shen Hu (明聖湖) while in the time of three Kingdom, it was called Chien Tang Hu (錢塘湖), the latter name being derived from the river, Chien Tang Kiang. Since the Hanchow city was built in the Sui Dynasty which is several hundred years after Han. so the history of Hsi Hu should be reckoned as much older than the city itself. On the other hand, Hsi Hu has never been noticed in any writings before the time when Shiuchinchu (水經註) was published. 相似文献
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INTRODUCTION Shuikoushan is the most important and well known mining district for production of silver, lead, zinc and pyrite in China. It is situated at about 65 li N. E. of Changning, 90 li S. of Hengyang and 620 li from Changsha, the Capital of Hunan. It has been visited by many geologists and mining 相似文献
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INTRODUCTION The specimens described in this paper were collected by Mr. Y. Y. Lee from the Meitien Limestone, Meitien, Ichang South Hunan. According to Mr. Lee this limestone occurs in isolated outcrops overlying the Lungtan 相似文献
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INTRODUCTION One of the major structural features in north China is the great fault system in central Shensi and Shansi known as the Weiho (渭河) Graben and Fenho (汾河) Craben respectively (Fig. 1). Dr. Bailey Willis seems to 相似文献
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ANDREI A. VELICHKO OLGA K. BORISOVA ELLA M. ZELIKSON 《Boreas: An International Journal of Quaternary Research》2008,37(1):1-19
Main climatic indexes (mean January, July and annual temperatures; duration of the frost‐free period; seasonal and annual precipitation; and annual potential evaporation) are estimated for the Last Interglacial Eemian–Mikulino–Kazantsevo–Oxygen Isotopic Substage 5e) climatic optimum in northern Eurasia. Reconstructions are based on the palaeofloristic data from 29 sites. The distribution of temperature deviations from present‐day values in northern Eurasia, as well as in the northern hemisphere as a whole, indicates certain areas where temperatures during the Last Interglacial climatic optimum were lower than at present. The greatest positive deviations occurred in the high latitudes and gradually decreased towards mid‐latitudes. At about 45°N the mean January temperature was close to that of the present day. For the mean July temperature, the zone with minor deviations is situated further to the north, at 55°N. South of 50°N, an area with small negative temperature deviations from the present‐day values is reconstructed. A similar decrease in temperature deviations from high to low latitudes was the general tendency in various warm epochs, including the Holocene and the Eocene optima. In the arid and semi‐arid regions of northern Eurasia, a considerable increase in precipitation took place, while air temperatures were close to those of the present or even slightly lower. Another peculiarity of the climate in the Last Interglacial climatic optimum relates to the meridional temperature gradient, one of the factors strongly influencing the intensity of the Westerlies in the mid‐latitudes of the northern hemisphere. Our reconstructions for northern Eurasia tend to contradict this rule. The paradox can be explained by a compensation mechanism: a substantial increase in winter temperature in Siberia indicates that the Siberian atmospheric High was weaker and smaller at the Last Interglacial climatic optimum than at present. The reduced role of the Siberian High was compensated by more frequent invasions of the Atlantic air masses from the west, even though the meridional temperature gradient was smaller than at present. 相似文献
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VALERY I. ASTAKHOV JOHN INGE SVENDSEN ALEXEI MATIOUCHKOV JAN MANGERUD OLGA MASLENIKOVA JAN TVERANGRE 《Boreas: An International Journal of Quaternary Research》1999,28(1):23-45
Glacial landforms in northern Russia, from the Timan Ridge in the west to the east of the Urals, have been mapped by aerial photographs and satellite images supported by field observations. An east-west trending belt of fresh hummock-and-lake glaciokarst landscapes has been traced to the north of 67°N. The southern boundary of these landscapes is called the Markhida Line, which is interpreted as a nearly synchronous limit of the last ice sheet that affected this region. The hummocky landscapes are subdivided into three types according to the stage of postglacial modification: Markhida, Harbei and Halmer. The Halmer landscape on the Uralian piedmont in the east is the freshest, whereas the westernmost Markhida landscape is more eroded. The west-east gradient in morphology is considered to be a result of the time-transgressive melting of stagnant glacier ice and of the underlying permafrost. The pattern of ice-pushed ridges and other directional features reflects a dominant ice flow direction from the Kara Sea shelf. Traces of ice movement from the central Barents Sea are only discernible in the Pechora River left bank area west of 50°E. In the Polar Urals the horseshoe-shaped end moraines at altitudes of up to 560 m a.s.l. reflect ice movement up-valley from the Kara Ice Sheet, indicating the absence of a contemporaneous ice dome in the mountains. The Markhida moraines, superimposed onto the Eemian strata, represent the maximum ice sheet extent in the western part of the Pechora Basin during the Weichselian. The Markhida Line truncates the huge arcs of the Laya-Adzva and Rogovaya ice-pushed ridges protruding to the south. The latter moraines therefore reflect an older ice advance, probably also of Weichselian age. Still farther south, fluvially dissected morainic plateaus without lakes are of pre-Eemian age, because they plunge northwards under marine Eemian sediments. Shorelines of the large ice-dammed Lake Komi, identified between 90 and 110 m a.s.l. in the areas south of the Markhida Line, are radiocarbon dated to be older than 45 ka. The shorelines, incised into the Laya-Adzva moraines, morphologically interfinger with the Markhida moraines, indicating that the last ice advance onto the Russian mainland reached the Markhida Line during the Middle or Early Weichselian, before 45 ka ago. 相似文献
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The research record on the quantification of sediment transport processes in periglacial mountain environments in Scandinavia dates back to the 1950s. A wide range of measurements is available, especially from the Kärkevagge region of northern Sweden. Within this paper satellite image analysis and tools provided by geographic information systems (GIS) are exploited in order to extend and improve this research and to complement geophysical methods. The processes of interest include mass movements such as solifluction, slope wash, dirty avalanches and rock- and boulder falls. Geomorphic process units have been derived in order to allow quantification via GIS techniques at a catchment scale. Mass movement rates based on existing field measurements are employed in the budget calculations. In the Kärkevagge catchment, 80% of the area can be identified either as a source area for sediments or as a zone where sediments are deposited. The overall budget for the slopes beneath the rockwalls in the Kärkevagge is approximately 680 t a−1 whilst about 150 t a−1 are transported into the fluvial system. 相似文献
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BY MAURO GUGLIELMIN ANTONI G. LEWKOWICZ HUGH M. FRENCH A. STRINI 《Geografiska Annaler: Series A, Physical Geography》2009,91(2):99-111
Ice blisters, typically 0.2–0.8 m high and 5–20 m long, develop annually on perennially frozen lakes in Northern Victoria Land. They are believed to be caused by hydrostatic pressures generated through progressive freezing of solute-rich water beneath the lake-ice cover during winter. Lake-ice blisters in the study area differfrom icing blisters described from the northern hemisphere. The latter are caused by hydraulic pressures and are found at locations such as river beds or spring sites on sloping terrain. The Antarctic lake-ice blisters reflect the occurrence of dry-based perennially frozen lakes with high salt contents in an extremely cold and arid environment. 相似文献