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S. N. Lal 《Journal of Earth System Science》1995,104(1):79-84
A refined mathematical equation is proposed to quantify the ambient activity of water during granulite fades metamorphism.
The thermodynamic calculations point to the low activity of water during metamorphism in the area around Anakapalle, Vishakhapatnam
district, A.P. Carbonic metamorphism seems to be responsible for the low activity of water during this metamorphism. Calc-silicate
rocks in the area, could have been the source of the CO2. 相似文献
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南京市地基稳定性区划图 总被引：1，自引：0，他引：1
为了城市土地的合理使用，保证建筑物的安全，目前在城市岩土工程问题中对土地的合理利用研究和评价方法不断涌现。本文根据南京市的基岩岩性、地貌特征、覆盖层厚度和第四纪松散沉积物分布情况，划分为五个基本类型，各个分区具有不同的工程地质特征。 相似文献
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JOHN R. DODSON RICHARD H. W. BRADSHAW 《Boreas: An International Journal of Quaternary Research》1987,16(2):113-123
Dodson, John R. & Bradshaw, Richard H. W. 1987 06 01: A history of vegetation and fire, 6,600 B.P. to present, County Sligo, western Ireland. Boreas , Vol. 16, pp. 113–123. Oslo. ISSN 0300–9483.
Two lake sites on metamorphic rocks with small catchments and one mor humus deposit have been analysed to assess the relative influences of fire, man and climate upon the regional and local vegetation of the Lough Gill region of County Sligo. The vegetation of the area was dominated by mixed woodland from 6,600 B.P. to 600 B.P. The first evidence of human impact on the forests was around 5,400 B.P. in the form of clearance for pasture. The intensity of human impact varied between sites, and there were periods of forest recovery as well as decline. From 600 B.P. widespread forest destruction took place, and pasture with heathland became predominant. Pinus sylvestris had a major presence until about 5,400 B.P. It declined from this time and had a patchy distribution by 2,000 B.P. The decline of Pinus was linked with the expansion of treeless peatland in what are presumed to be wet periods, and Pinus recovery in drier periods. Fire may have encouraged the spread of heathland at the expense of Pinus . Arbutus unedo pollen was found at Slish Lake as early as 1,900 B.P., suggesting that it is native to this area. Isolated trees survive today at woodland edges. Charcoal particles occurred in all the profiles. Fire was particularly associated with heathland communities, and may have been used as a management tool to improve grazing conditions. Some of the phases of woodland decline correlate strongly with charcoal input suggesting forest destruction by fire. 相似文献
Two lake sites on metamorphic rocks with small catchments and one mor humus deposit have been analysed to assess the relative influences of fire, man and climate upon the regional and local vegetation of the Lough Gill region of County Sligo. The vegetation of the area was dominated by mixed woodland from 6,600 B.P. to 600 B.P. The first evidence of human impact on the forests was around 5,400 B.P. in the form of clearance for pasture. The intensity of human impact varied between sites, and there were periods of forest recovery as well as decline. From 600 B.P. widespread forest destruction took place, and pasture with heathland became predominant. Pinus sylvestris had a major presence until about 5,400 B.P. It declined from this time and had a patchy distribution by 2,000 B.P. The decline of Pinus was linked with the expansion of treeless peatland in what are presumed to be wet periods, and Pinus recovery in drier periods. Fire may have encouraged the spread of heathland at the expense of Pinus . Arbutus unedo pollen was found at Slish Lake as early as 1,900 B.P., suggesting that it is native to this area. Isolated trees survive today at woodland edges. Charcoal particles occurred in all the profiles. Fire was particularly associated with heathland communities, and may have been used as a management tool to improve grazing conditions. Some of the phases of woodland decline correlate strongly with charcoal input suggesting forest destruction by fire. 相似文献
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S. A. Fedotov 《Lithology and Mineral Resources》2009,44(1):100-101
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Late Wisconsinan age glacial landforms and deposits indicate that an ice shelf of at least 60,000 km2 flowed northwestward into Viscount Melville Sound, probably from the M'Clintock Dome of the Laurentide Ice Sheet. The ice shelf overlapped coastal areas and laid Winter Harbour Till up to 125 m above present sea level on the southern coast of Melville Island, to 135 m on Byam Martin Island, to possibly 90 m on the northeast tip of Banks Island, and to 150 m on the north coast of Victoria Island. The contemporary sea level was 50 to 100 m higher than present (it now rises eastward). A maximum age of 10,340 ± 150 yr B.P. for the till, and thus the ice-shelf advance, is provided by shells in marine sediments which underlie it, whereas a minimum age of 9880 ± 150 yr B.P. is provided by overlying shells that postdate the ice advance. The major advance of shelf ice into Viscount Melville Sound may be the result of the rapid disintegration of the M'Clintock Dome while the climate ameliorated in the western Arctic. 相似文献
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中国地质学家李四光与当时苏联地学界来往交流紧密,他对地质学的贡献得到了苏联地质学家的高度评价。1958年,苏联科学院全体大会选举李四光为苏联科学院院士,并授予卡尔宾斯基金质奖章;该奖章是1947年由当时的苏联科学院和俄罗斯科学院共同发起的、对地质科学有突出贡献的科学家最高单人奖励,李四光是第六位获奖人,也是至2017年止唯一获此殊荣的外籍地质学家,他的获奖理由是:在地质、古生物、地层和矿产研究工作的综合贡献。李四光有两部著作在苏联被译成俄文出版,分别是1952年的《中国地质学》和1958年的《中国西北部的旋卷构造》,这两部译作对当时的苏联地质界产生了很大影响,极大地推动了李四光学术思想的广泛认知;"地质无国界",中国地调百年的发展历程也有着俄罗斯地学理论、规范、方法实践的烙印,在新的"一带一路"合作倡议和李四光学术精神传承下,中俄、中国与中亚在地学领域的交流合作将不断深化,硕果累累。 相似文献
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《第四纪科学杂志》2008,23(1):no-no
Journal of Quaternary Science Published online 9 August 2007. DOI: 10.1002/jqs.1118 The above paper was incorrectly titled. The correct title should be: Comment: Middle Pleistocene sedimentation at Pakefield, Suffolk, England J. R. LEE, J. ROSE, I. CANDY and R. W. BARENDREGT (2006) Journal of Quaternary Science 21 : 155–179 The error will be corrected prior to print publication. 相似文献
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在两个斜方辉石样品中观察到G.P.区亚稳相。内蒙古暗色辉长岩古铜辉石成分是En_(77)Fs_(18·6)Wo_(4·4),其高分辨象显示了密集的单层G.P.区;玄武岩中变辉长岩包体古铜辉石成分是En_(72·2)Fs_(25·7)Wo_(2·1),具双层G.P.区。该包体与具多层G.P.区的月岩橄长岩相似,后期冷却极快。在地体火成岩体结晶和冷却过程中易出现单层G.P.区,而岩体的大小,冷却的快慢可能影响G.P.区的密度。对N-14样品不同放大倍数的高分辨象G.P.区线密度和面密度的统计值同样具代表性。文中设想了G.P.区出溶的假二元系相图。 相似文献