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91.
This study analyzes the response of glacier to climate change during the past 49 years in Urumqi River source region, the
Tianshan Mountains of China. The temporal and spatial variations of winter mass balance (bn-w) at different time scales were
analyzed to identify their response to climate change during 1988–2006 (The observation of winter mass balance observation
began in 1988) on the Glacier No.1 at the headwaters of the Urumqi River, Tianshan Mountains, China. The winter accumulation
shows a significantly decreasing trend. The results show that the cumulative values on Glacier No.1 is 2,202 mm water equivalent
during 1988–2006 and the mean values is 116 mm a−1. Furthermore, the trend analysis of the winter mass balance indicates a rapid decrease since 1990, and the mean mass balance
is only 79 mm a−1 during 1997–2006. Winter mass balance correlates well negatively with the total evaporation from September to April (r = −0.68, α = 0.01), and positively with the total precipitation from September to April (r = 0.74, α = 0.01). However, winter mass balance shows a weak correlation with mean minimum air temperature during September
to April (r = −0.35), and runoff on September (r = −0.13). 相似文献
92.
Ding Tiping Liu Yushan Wan Defang Liu Zhijian Li Jincheng Zhang Guilan Institute of Mineral Deposits Chinese Academy of Geological Sciences Beijing 《《地质学报》英文版》1992,66(3):271-282
Experiments for oxygen isotope exchange between ferberite and water were carried out and the followingequation on oxygen isotope fractionation between ferberite and water against temperature was obtained:Combining this equation with the equation of Clayton et al. (1972) on oxygen isotope fractionation be-tween quartz and water, an equation on oxygen isotope fractionation between quartz and ferberite was ob-tained:The Bigeleison-Mayer function method was used to calculate the oxygen isotope fractionation betweenquartz and ferberite. The theoretical curve obtained agrees with the experimental calibration results quite wellin the temperature range of study.The above calibrated equation has been used in 5 world famous tungsten deposits to determine their tem-peratures of formation. The results show that the temperature range for an idividual deposit determined by thisgeothermometer agrees with those obtained from fluid inclusion determination and other isotopegeothermometers. 相似文献
93.
中亚造山带南缘中—新元古代地壳的揭示——来自北山—阿拉善北部钻遇碱性花岗岩的年代学和Hf同位素示踪研究 总被引:1,自引:0,他引:1
前寒武纪微陆块是北山—阿拉善北部增生造山带的重要组分,旱山、雅干和珠斯楞—杭乌拉地区的前寒武纪基底是否存在学界尚存争议.居延海介于北山造山带北部和阿拉善地块北缘的构造衔接部位,受限于巴丹吉林沙漠覆盖,岩石露头极少,我们通过钻井工程,钻遇一套晚石炭世碱性花岗岩,锆石U-Pb年龄和Hf同位素特征揭示,该花岗质岩浆锆石结晶年龄为(312±1)Ma(MSDW=0.46,n=18)和(315±2)Ma(MSWD=0.93,n=15),具有正的εHf(t)值,介于+0.8~+4.4之间,平均值为+2.2,对应二阶段模式年龄TDM2为1048~1267 Ma,平均值为1183 Ma,具有古老地壳的源区属性.通过与旱山构造带、雀儿山构造带、雅干构造带和珠斯楞—杭乌拉构造带的晚石炭世花岗质岩浆对比分析,结合旱山构造带、雅干构造带和珠斯楞—杭乌拉构造带0.9 Ga花岗质岩石的出露以及区域上的重磁资料解译,我们认为旱山、雅干和珠斯楞—杭乌拉构造带存在中—新元古代地壳,且可开展进一步的衔接关系研究. 相似文献
94.
碧口岩群硅质岩成因及地质意义 总被引:1,自引:0,他引:1
碧口块状硫化物矿床直接赋矿主岩硅质岩地质特征及常量、微量、稀土元素组成表明,碧口岩群硅质岩为同火山岩喷流热水沉积成因。碧口岩群硅质岩常量元素富Fe、贫Si,为典型热水沉积成因;其微量元素、稀土元素特征均与现代大洋热水沉积物相似。热水硅质岩Eu异常与古流体温度存在密切关系,Eu/Eu特征显示筏子坝、铜矿坡为较高温度喷流产物,而大茅坪、黑窝子、铜矿梁、周家坡则为较低温度下的产物。 相似文献
95.
本文讨论了岩石试样在加载全过程中的声发射特征、不同岩石声发射全过程曲线的分类以及类型的确定方法;对新疆塔里木盆地北部油区井下和地表试样进行了统计、分类,确定出该油区泥岩、砂岩声发射全过程曲线存在Ⅰ、Ⅲ两种类型;白云岩、灰岩、玄武岩声发射全过程曲线具有Ⅰ型特征。 相似文献
96.
Features of the Early Palaeozoic Mantle beneath Langao County and Its Formation Mechanism 总被引:1,自引:0,他引:1
XU Xueyi HUANG Yuehu XIA Linqi XIA ZuchunXi ''an Institute of Geology Mineral Resources Chinese Academy ofGeological Sciences Youyi Ro Xi''an Zhou Jian Fei Zhenbi 《《地质学报》英文版》1999,73(3):356-365
Phlogopite-amphibole pyroxenite xenoliths contained in an Early Palaeozoic alkali subvolcanic lam-prophyre complex in Langao County, Shaanxi Province, are metasomatized mantle xenoliths, composed mainly of clinopyroxene, amphibole, phlogopite, apatite, pervoskite, ilmenite and sphene with well-developed subsolidus metamorphism-deformation textures, such as "triple points" and "cataclastic boundaries" . Minerological studies indicate that clinopyroxene is rich in SiO2 and MgO and poor in TiO2 and Al2O3, which is notably different from magmatogenic deep-seated megacrysts and phenocrysts formed in the range of mantle pressure. Amphibole and phlogopite have the compositional feature of mantle-derived amphibole and phlogopite. Sm-Nd isotope studies suggest that the metasomatized mantle beneath Langao County is the product of metasomatism of primitive mantle by melt (fluid) derived from the mantle plume, and the mantle metasomatism occurred 650 Ma ago. The process of mantle metasomatism changed from mantle me 相似文献
97.
灰色聚类分析在煤矿瓦斯分区中的应用 总被引:1,自引:0,他引:1
以灰色理论为依据,结合南屯煤矿瓦斯分布规律的研究,探索了利用灰色聚类分析进行煤矿瓦斯分布规律研究的一般方法。 相似文献
98.
XU Shaokang XIA Xuehui YUAN Congjian WANG Bingquan YAN Fei YAN Shengxian ZHENG Xingquan 《《地质学报》英文版》2008,82(4)
The new type hot water sedimentary rock - magnetite-fluorite rock occurs as quasi-layers inflat parts of contact zones between rock body and strata in Bamiaushan of Changshan County,Zhejiang Province, China. The main mineral assemblage is fluorite magnetite cassiterite. The rockshows typical laminated structure and obvious mosaic texture. Its formation temperature is between123℃-160℃, averaging at 142℃. The major chemical composition of the rock includes CaF2, SiO2,Al2O3, FeO, and Fe2O3; the high-content microelement association includes W, Sn, Be, Rb, Sr, S, andCl; and the total content of REE is low (∑REE between 35.34x10-6-38.35x10-6), showing LREEenrichment type of distribution pattern. Diagenesis: driven by the tectonic stress, the formation waterheated in the deep strata had moved along the fissures or fractures in strata and had extractedcomponents from the strata on the way, and finally stagnated in the flat parts of contact zones betweenrock body and strata. With drop in temperature, magnetite and fluorite were separated from the hotwater and precipitated alternately, forming this hot water sedimentary rock with new typemineralogical composition, typical laminated structure, obvious mosaic texture and sub-horizontaloccurrence. The characteristics of the new type mineralogical composition, sedimentary tectonicenvironment and chemical composition are different from that of the well-known traditionalhydrothermai sedimentary rocks. 相似文献
99.
大兴安岭东南部油气资源勘查区重磁异常初步解释 总被引:2,自引:0,他引:2
区域重磁异常的初步解释表明,西拉木伦河以北的松辽盆地外围地区存在诸多中、新生代盆地,发育3条NW向深大断裂和近NEE向的弧形构造.1∶20万重力异常显示,本区中、新生代盆地边界具有较明显的梯度异常特征,1∶5万航磁异常可较为清晰地勾画中新生代火成岩的分布.重、磁、电剖面联合反演揭示,中生代地层厚度1~4km,古生界规模宏大,厚度可达4~6km,是本区寻找油气的重要层位;古生界含油气盆地基底为志留系及更老地层;大兴安岭NE向展布的花岗岩具有蘑菇状侵入特征.通过重、磁异常联合反演,消除火成岩影响,得出突泉和扎鲁特地区的中生代基底深度1.5~4km,古生代的基底深度为2~6km. 相似文献
100.
包气带土壤中氨氮污染迁移规律已成为近年来国内外学者研究的重点,目前在氨氮污染迁移规律研究中采用柱实验模拟以及软件模拟的方法较多,土壤生物技术则广泛应用于污染物降解领域,而在污染物迁移规律研究中应用较少。本文采用变性梯度凝胶电泳(DGGE)技术、16S rRNA序列分析技术以及典范对应分析相结合,对华北平原3个典型氨氮污染区土壤表层至包气带剖面微环境的细菌垂直分布特征及群落结构进行研究。结合污染区土壤理化性质分析,认为包气带土壤剖面的细菌群落中存在着与氮循环、硫酸盐代谢等过程偶联的优势细菌类群,说明土壤微环境中细菌群落分布明显受氨态氮、硝态氮、亚硝态氮和硫酸盐的分布影响,进一步表明污染土壤优势菌群的群落结构信息是描述包气带土壤环境氨氮污染物迁移规律的重要参数。 相似文献