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Wang YingMin Xu Qiang Li Dong Han JianHui Lü Ming Wang YongFeng Li WeiGuo Wang HaiRong 《科学通报(英文版)》2011,56(14):1488-1494
A huge submarine fan is discovered through the research of the seismic and borehole data in the binding site of Yinggehai basin and Qiongdongnan basin in northwestern South China Sea.The fan,mainly formed during Late Miocene (Huangliu period) has an area over 10000 km 2 and maximum thickness of over 2000 m.It is characterized by a wedge-shaped oblique progradation configuration on the dip profile and a hummocky bidirectional progradation configuration on the strike profile.The core and Logging data from the well YC35-1-2 located in the front side of the fan indicate that sandy gravity flow deposits are predominant in lower Huangliu Formation and change to interbeds of sand and mud in upper Huangliu Formation.The fan is interpreted as a sand/mud-rich submarine fan in combination with the bathyal geological background of Huangliu period.A preliminary analysis of provenance indicates that neither the Guiren Uplift in the west nor the Hainan Uplift in the north can serve as the major provenance for the submarine fan.The provenance is considered to be from the Red River,based on the sedimentary facies study of the Huangliu Formation in Yinggehai basin.The fan is thus named as "Red River submarine fan".The Red River depositional system consists of the Red River submarine fan,the Red River delta,and associated submarine canyons.The discovery of the Red River submarine fan provides important information for the research of the uplift of Tibetan Plateau and the evolvement of Red River Fault Zone.Furthermore,it also points out a new direction for the deepwater hydrocarbon exploration in the northern South China Sea. 相似文献
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滇西和滇南地区几件青铜时代铜器的科学分析 总被引:1,自引:0,他引:1
利用科学分析手段,对滇西、滇南出土的10件铜器进行了初步的科学分析,包括化学成分分析和金相组织鉴定。结果表明:这些铜器的材质为红铜、铜锡二元合金、铜锡砷三元合金、铅锑砷铜和铜锡铅砷四元合金。体现了滇西地区铜器制作工艺和合金配比的多样化特点,表明了滇西与其他地区青铜文化存在技术交流的可能性。 相似文献
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近50a葫芦河流域气候变化特征 总被引:2,自引:2,他引:2
根据静宁、秦安两站的水文气象资料,分析了葫芦河流域近50a气候变化特征.采用Mann-Kendall法分析,结果显示近50a气温总体呈上升趋势,降水量呈下降走向.利用Meyer小波及Morlet小波分别分析并相互检验校正葫芦河流域年均气温及年降水量的主要变化周期,其中:年平均气温普遍存在30a以上,22,12~14,10a左右的中长周期以及4~7,2~3a的短周期,而年降水量存在30a以上,20,12~14,10a左右的中长周期以及6~8,2~4a的短周期.近50a葫芦河流域河川径流的变化主要受当地降水波动的影响. 相似文献
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李效文 《贵州师范大学学报(社会科学版)》2011,(5):82-85
在红色题材影视创作的书写系统中,贵州被加工成梦幻奇观、英雄神话的空间固然能够为受众提供某种程度上的观赏性消费满足,但是,决不应该让视听文本里的"西部空间"失去自治性、多样性的可能去受控于市场操作的过程;贵州不应是一个从现实中被抽离出来并放置到梦幻和神话表意系统中的、抽象的、空洞的符号,而应是一个建立在现实地理空间基础上的、具有区域特征和民族文化特色的、历史与现实相生的人文系统。 相似文献
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目的:分析云南不同地区、不同年代分离鼠疫菌的基因表型。方法:采用随机引物扩增技术(RAPD)对菌株进行分析。结果:共检测了28株鼠疫菌,除一株外,27株均显示有13条带型,并与假结核菌和小肠结肠炎菌有明显的区别。结论:云南家、野两型鼠疫菌株可能具有相同的随机引物扩增基因表征。 相似文献
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Clay minerals in surface sediments of the Pearl River drainage basin and their contribution to the South China Sea 总被引:5,自引:0,他引:5
LIU ZhiFei Christophe COLIN HUANG Wei CHEN Zhong Alain TRENTESAUX CHEN JianFang 《科学通报(英文版)》2007,52(8):1101-1111
Clay minerals have played a significant role in the study of the East Asian monsoon evolution in the South China Sea by being able to track oceanic current variations and to reveal contemporaneous paleoclimaUc changes prevailing in continental source areas. As one of the most important rivers inputting terrigenous matters to the northern South China Sea, the Pearl River was not previously paid attention to from the viewpoint of clay mineralogy. This paper presents a detailed study on clay minerals in surface sediments collected from the Pearl River drainage basin (including all three main channels, various branches, and the Lingdingyang in the estuary) by using the X-ray diffraction (XRD) method. The results indicate that the clay mineral assemblage consists dominantly of kaolinite (35%-65%), lesser abundance of chlorite (20%-35%) and illite (12%-42%), and very scare smectite occurrences (generally 〈5%). Their respective distribution does not present any obvious difference throughout the Pearl River drainage basin. However, downstream the Pearl River to the northern South China Sea, the clay mineral assemblage varies significantly: kaolinite decreases gradually, smecUte and illite increase gradually. Additionally, illite chemistry index steps down and illite crystallinity steps up. These variations indicate the contribution of major kaolinite, lesser illite and chlorite, and very scarce smecUte to the northern South China Sea from the Pearl River drainage basin. The maximum contribution of clay minerals from the Pearl River is 72% to the northern margin and only 15% to the northern slope of the South China Sea. In both glacials and interglacials, kaolinite indicates that the ability of mechanical erosion occurred in the Pearl River drainage basin. 相似文献
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使用涡度相关蒸散数据验证表明SEBS-METRIC方法可以用来估算黑河流域中游地区作物农田蒸散.结果显示:黑河流域中游地区作物生长季内ET总量空间差异大(398~709 mm,平均567 mm).在作物不同生长阶段,ET在时间和空间上变化剧烈.在区域平均水平上,生长初期、生长中期1、生长中期2和生长后期的ET占全生长季ET总量的比例分别为10.24%,29.44%,47.11%,13.21%,各生长阶段区域平均日ET依次为1.45,3.28,3.52,2.08 mm/d.ET月份变化明显,3月最小,4,5月迅速增大,6月达到生长季的蒸散高峰,7,8月有所降低,维持在一定水平,9月作物进入生长末期,迅速降低. 相似文献
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滇西龙川江盆地沉积体系特征及与砂岩铀矿成矿 总被引:7,自引:0,他引:7
龙川江盆地是滇西新生代造山带内部发育的小型山间断陷陆相沉积盆地.通过分析盆地内沉积体系类型、特征及空间展布模式,提出了初始成盆阶段主要发育冲积扇沉积体系,盆地扩张阶段则以发育冲积扇、扇三角洲、滨-浅湖沉积体系组合的观点.探讨了沉积体系对砂岩型铀矿的控制作用,认为铀矿床定位于冲积扇扇体上,冲积扇与扇三角洲沉积体系砂体是砂岩型铀矿赋存的主要场所. 相似文献
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Estimation of wind erosion rates by using ~(137)Cs tracing technique:A case study in Tariat-Xilin Gol transect, Mongolian Plateau 总被引:3,自引:0,他引:3
《科学通报(英文版)》2008,(5)
Wind erosion is one of the major environmental problems in semi-arid and arid regions. Here we es- tablished the Tariat-Xilin Gol transect from northwest to southeast across the Mongolian Plateau, and selected seven sampling sites along the transect. We then estimated the soil wind erosion rates by using the ~(137)Cs tracing technique and examined their spatial dynamics. Our results showed that the ~(137)Cs inventories of sampling sites ranged from 265.63±44.91 to 1279.54±166.53 Bq·m~(-2), and the wind erosion rates varied from 64.58 to 419.63 t·km~(-2)·a~(-1) accordingly. In the Mongolia section of the transect (from Tariat to Sainshand), the wind erosion rate increased gradually with vegetation type and climatic regimes; the wind erosion process was controlled by physical factors such as annual precipitation and vegetation coverage, etc., and the impact of human activities was negligible. While in the China section of the transect (Inner Mongolia), the wind erosion rates of Xilin Hot and Zhengxiangbai Banner were thrice as much as those of Bayannur of Mongolia, although these three sites were all dominated by typical steppe. Besides the physical factors, higher population density and livestock carrying level should be responsible for the higher wind erosion rates in these two regions of Inner Mongolia. 相似文献
