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11.
通过对桃山、诸广复式岩体的深入研究,得出铀、钍元素在本地区花岗岩中具有以下地球化学特征及地球化学行为:1.岩体的铀、钍丰度与岩体外接触带的变质岩铀,钍丰度具同步增长特点;2.铀与硅、钾、钠关系密切,并有随钾增长,及随铀增长二种趋势,而钍则与TiO_2、FeO、MnO关系密切;3.钍在花岗岩中分布型式为正态分布,变异系数较铀小,而铀在花岗岩中分布型式为正态分布及对数正态分布,变异系数略高,显示了铀有某种富集可能;4.铀在花岗岩中地球化学行为,表现有二个富集高峰,既有在结晶早期富集在各类副矿物中的早富集特征,也有随花岗岩形成和演化富集在晚期的晚富集特征。二个富集途径,即随Si、K增高和随Si、Na增高途径。 相似文献
12.
Researches on Plants from the Lower Devonian Xujiachong Formation in the Qujing District, Eastern Yunnan 总被引:1,自引:0,他引:1
WANG Deming HAO Shougang LIU Zhenfeng School of Earth Space Sciences Peking University Beijing 《《地质学报》英文版》2002,76(4):393-407
Fossil plants Hedeia sinica Hao et Gensel 1998, Huia gracilis Wang et Hao 2001 and Guangnania cuneata Wang et Hao are described from the Lower Devonian Xujiachong Formation, the Qujing district, eastern Yunnan, China. They contribute to our knowledge of the flora in this district. Based on the occurrence of common plants (Hedeia, Huia, Guangnania and Zosterophyllum australianum) and their horizons, it is proved for the first time that the mid-lower assemblage of the Xujiachong flora is comparable with the Early Devonian ((late) Pragian) Posongchong flora of southeastern Yunnan and the upper Baragwanathia flora of Australia. In view of this fact and the stratigraphic sequence, the mid-lower part of the Xujiachong Formation is considered to be of (late) Pragian age. Through comprehensive analyses of plant, bivalve and fish assemblages and the lithology, the upper part of the Xujiachong Formation is dated to be of early Emsian age. The Xujiachong flora belonged to the northeastern Gondwana palaeophytogeogr 相似文献
13.
1INTRODUCTIONIntheHuanghe(Yellow) Riverbasin, soilerosionisaseriousproblem,whilerunoffandsedimentyieldsim-ulation hasnotbeenextensivelystudiedonthebasisofGIS(GeographicInformationSystem) and dis-tributedhydrologicalmodel.Inthisstudy,theLushiwatershed,whichislocatedattheupstreamoftheLushiHydrologicalStationintheLuoheRiver—thebiggesttributary oftheHuanghe Riveranddown-streamofXiaolangdiDam,isselectedasthestudyarea.ThelevelofsoilerosioninLushiwatershedismoderatein theHuangheRiverbas… 相似文献
15.
首先研究了河南"75·8"强降水事件的极端异常特征,然后从水汽通量的角度定性分析这次事件的水汽输送特征,最后采用了Hysplit模型定量分析了不同源地的水汽来源对河南"75·8"强降水的贡献率。研究表明,1975年8月5-8日在河南省发生的是一次大范围持续性极端降水过程,事件发生期间区域平均降水程度超过其气候平均值3倍标准差。强降水事件是在中高纬度环流异常和台风共同作用下发生的,贝加尔湖以东阻塞高压和副热带高压合并阻挡了7503号台风北上。定量计算结果进一步表明,河南"75·8"强降水的水汽来源与7503号台风具有十分密切的联系。 相似文献
16.
HAO Baiwu 《《地质学报》英文版》2010,84(6):1500-1513
<正>The Hadamiao granodiorite,located on the northern margin of the North China platform and acting as the country rock of gold deposits in the Hadamiao region,was formed in the same age and similar tectonic settings with the Hadamiao gold deposit and the large-scale Bilihe gold deposit in the same area.By using the LA-ICP-MS method,the U-Pb age obtained is 267±1.3 Ma,which represents the crystallized age of the granodiorite,and that of the xenolithic zircon is 442.8±5 Ma. Base on the main elements,it exhibits the features of calc-alkaline to high-potassium calc-alkaline series,low silicon,and quasi-aluminous I-type granites,and with high magnesium(Mg~#=0.45-0.57) and high sodium contents(Na_2O/K_2O=0.98-2.29).The SREE values(81.6-110.15 ppm) are relatively low,the fractionations between LREE and HREE are obvious,showing a right-inclined dispersion in the REE distribution diagram.Compared with the primitive mantle,the rock is relatively rich in LREE(La and Ce),LILE(K,Sr,and Th),and intensively depleted in HFSE(Ti,P,Nb and Ta).The ratios of Sr/Y and(La/Yb)_N and the contents of Rb,Nb and Y are relatively low,the Sr values are high (436.35-567.26 ppm),and the Yb contents of most samples are low(1.25-1.8),which indicate the features of typical continental margin arc and adakitic rocks.According to the values ofε_(Nd)(t)(-2.4 to +0.2) and I_(Sr)(0.7028-0.7083),and variations of the La/Sm ratios,the Hadamiao granodiorite was formed from mixing of the thickened molten lower crust and the mantle wedge substances.The rock was related to the southward subduction and accretion of the Paleo-Asia Ocean in the Late Paleozoic, being Late Paleozoic magma of the continental margin arc formed on the basement of the Early Paleozoic accretion complexes,and showing a trend of turning into adakitic rocks,which indicates their great metallogenic(Au) potential. 相似文献
17.
18.
正China’s Ministry of Land and Resources announced on 27th February 2014 that proven reserves of oil,natural gas and coal continued to increase significantly,and that their production shows a steady increase.This greatly improves China’s support capacity of fossil fuel resources.Oil resources:In 2013,China newly discovered oil geological reserves yielded 10.84×108 t,and 相似文献
19.
开发的中间件,将用于支持不同交换机的计算机电话集成,实现交换机和应用系统之间的电话服务请求和状态消息传递,协调语音和附加数据同步转移,使客户端应用程序能够与服务器之间进行数据交换,屏蔽不同交换机拥有的CT中间件协议和CT中间件接口,使应用程序员无需关心消息是如何在计算机、交换机、自动语音应答服务器之间传递,无需关心交换机的私有协议与接口,而专注于客户端的应用开发,并且使客户端应用程序兼容不同交换机. 相似文献
20.
Zihao JIN Guanghui YUAN Yingchang CAO Keyu LIU Yanzhong WANG Jianye SUN Xiluo HAO Ling ZHOU Yihan WEI Shuqi WU 《中国科学:地球科学(英文版)》2022,65(2):299-316
During the burial processes of deep/ultra-deep hydrocarbon reservoirs,the interactions between hydrocarbon-bearing fluids and reservoirs significantly affect the quality evolution of hydrocarbons and reservoirs;thus,this topic requires further investigation.In this study,the continuous evolution and the coupling mechanisms in various anhydrous and hydrous nC16H34-(water)-(calcite)systems in fused silica capillary capsules(FSCCs)were investigated using laser Raman spectroscopy,fluorescence color analysis,and fluorescence spectroscopy,and the mineral alterations were analyzed using scanning electron microscopy(SEM).The experimental results show that extensive organic-inorganic interactions occur in the systems if water is present,and different inorganic components have different effects on hydrocarbon degradation.Distilled water promotes freeradical thermal cracking and steps oxidation,forming more low-molecular-weight hydrocarbons,CO2,and organic acids(e.g.,acetic acids)but suppresses the free-radical cross-linking,generating less high-molecular-weight hydrocarbons.However,in the presence of CaCl2 water,the yields of hydrocarbon gases are lower than in the distilled water system because high concentrations of Ca ions inhibit the generation of free radicals.Calcites,which exhibit different surface reactivities in different fluid conditions,affect hydrocarbon degradation in different ways.In the anhydrous nC16H34-calcite system,calcites promote the generation of both hydrocarbon gases and high-molecular-weight hydrocarbons.In contrast,in the hydrous nC16H34-distilled(CaCl2)watercalcite system,calcites promote the generation of hydrocarbon gases and suppress the generation of high-molecular-weight hydrocarbons.Calcite also reacts with organic acids via surface reactions to form secondary pores.Therefore,except for the formation temperature and pressure,organic-inorganic interactions are controlled by multiple factors,such as the water saturation,water type,water salinity,and the mineral content,resulting in different evolutions of the hydrocarbon degradation and reservoir properties. 相似文献