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161.
Ye Delong Lu Fengxiang Zhu Qinwen Zheng JianpingFaculty of Earth Sciences China University of Geosciences Wuhan 《中国地质大学学报(英文版)》1997,(1)
StudyonEogeneBasalts:ImplicationoftheDeepProcesovertheBohaiwanBasinEvolution*YeDelongLuFengxiangZhuQinwenZhengJianpingFaculty... 相似文献
162.
陕西段家坡黄土剖面中布容/松山古地磁界线附近铱异常的发现及其启示 总被引:3,自引:0,他引:3
利用高灵敏度放射化学中子活化分析方法,对我国陕西段家坡黄土剖面早-中更新统(约0.73Ma)沉积界线附近铱和其它元素的丰度进行了测定。结果表明,在布容/松山(B/M)古地磁界线附近铱的含量明显增大,最大值为46.3pg/g。相对于整个剖面的平均背景值(约15pg/g)大约富集了3倍。用地壳元素钪进行标准化之后,铱异常十分明显,而其它元素在界线附近则没有变化。黄土剖面上铱异常的赋存层位与西南太平洋钻 相似文献
163.
Vanadium-bearing stone coal is a new vanadium resource;recovery ofV_2O_5 from the coal has been investigated.It has been found that a satisfactoryextraction of V_2O_5 depends on both the oxidation of V and its reaction with so-dium salt.V in the coal ash of Yushan mainly exists in two oxidation states:98%V(Ⅲ)and2%V(Ⅳ).The distribution of valency of V shows that organicmatter determines V valency at low temperatures,at about470℃,V(Ⅲ)iscompletely oxidized to V(Ⅳ);above500℃,the temperature is the most impor-tant factor for the oxidation of V .At higher temperatures no more V is oxidizedto V(Ⅴ);an equilibrium is established after92%of V is oxidized to V(Ⅴ).The roles of NaCl in the recovery of V_2O_5 from the coal ash were discussed.The best conditions for roasting are temperature750-800℃for1 h.underthe oxidation-chlorination atmosphere.When the ore:NaCl=100:10 by weight,η_roast reaches85.5%.According to the results,a flowsheet for V_2O_5 extrac-tion from coal ash has been proposed. 相似文献
164.
华南二叠-三叠系的事件地层与生物地层界线 总被引:9,自引:1,他引:9
华南二叠-三叠系界线研究应严格区分事件地层界线与生物地层界线。“界线粘土”层的底界即为事件地层界线。生物地层界线定义不能与“混生层”或“过渡层”的概念连在一起。长兴煤山忠心大队剖面是最好的二叠-三叠系全球界线层型剖面点(GSSP)。二叠-三叠系生物地层界线定义为HindeodusparvusMorphotype1的首次出现,其位置就在长兴剖面界线层(混生层)2的内部,比事件地层界线高15cm。HindeodusparvusMorphotype1的首次出现,即为长兴阶的顶界。 相似文献
165.
内蒙古二连盆地产在下白垩统碎屑岩系中的砂岩型铀矿床,其矿化与地沥青密切相关,有铀矿物存在之处必有地沥青;岩石中也普遍含地沥青。笔者通过蚀刻α径迹示踪,对铀含量在(200~1770)×10~(-6)的碎屑岩进行扫描电镜分析,采用分子量计算方法确定了该地区含铀碎屑岩中的铀是以多种超显微铀矿物形式存在。其中,以赛汉高毕铀矿床为代表,铀主要形成复成分磷钙铀矿。其它铀矿床也普遍有复成分磷钙铀矿产出:巴彦乌拉矿床样品因钙含量低、硅含量高,则铀石多于复成分磷钙铀矿;道尔苏矿床以铀石和磷铀矿为主,有少量沥青铀矿及复成分磷钙铀矿;哈达图矿床主要是沥青铀矿,未见复成分磷钙铀矿。除了地沥青之外,各矿床中与铀矿物共生的主要矿物还有草莓状、鲕粒状黄铁矿。由此推断,铀矿床的可能成因是:来自盆地深部的UH_3、PH_3、CaH_2、SiH_4、FeH_2、H_2S等在伴随油气向上运移过程中,由于温度、压力降低和氧化作用而发生分解及凝聚,形成草莓状、鲕粒状黄铁矿;同时派生出含U、P、Si、Ca等的氧化物的低温热水溶液,并最终结晶析出铀矿物,形成有大量黄铁矿共生的铀矿体;而油气经过长期挥发,最终演变成地沥青,成为铀矿物的载体。 相似文献
166.
河套及其邻近不稳定积雪区积雪日数时空变化规律研究 总被引:3,自引:8,他引:3
利用河套及其邻近地区(30°~43°N,102°~120°E)240个地面气象观测站1951-2006年的积雪日数资料,采用EOF/REOF进行分解,分析了该区积雪的时空异常分布情况.结果表明:河套及其邻近地区积雪日数有3个主要的分布型,第1种类型为全区一致地偏多(偏少)型,相似年份有13 a;第2种类型为南多(少)北少(多)的南北相反分布型,相似年份有7 a;第3种类型为东多(少)西少(多)的东西相反分布型,相似年份有2 a.对年积雪日数进行REOF分解可将研究区域分为6个气候分区.利用Morlet小波分析表明,研究区域年积雪日数变化存在准18 a周期.在全球变暖的大背景下,研究区域的年积雪日数整体呈减少的趋势,减少最显著的在高纬度和高海拔地区. 相似文献
167.
钛基柱撑累托石矿物材料的研究 总被引:17,自引:0,他引:17
在氮气环境中用TiCI4和HCI制成钛基柱撑液,采用离子交换法,用[Ti20O32(OH)12(OH2)18]^4 Dawson型Ti多核阳离子,交换累托石蒙皂石质晶层中的Na等阳离子,制成钛基柱撑累托石。通过电子探针定量分析、X射线衍射、红外光谱、热分析及魔角旋转核磁共振等方法,对钛基柱撑累托石的成分、结构和热稳定性进行了表征。钛基柱撑累托石具1.6nm的层孔隙,是一种很有应用前途的柱撑粘土矿物材料,有望在催化剂载体及环保材料领域中得到广泛的使用。 相似文献
168.
Chongwen Yu 《地学前缘(英文版)》2011,2(4)
By applying the ‘theory of synchronization' from the science of complexity to studying the regional regularity of ore formation within the Nanling region of South China,a characteristic target-pattern regional ore zonality has been discovered.During the early and late Yanshanian epoch (corresponding respectively to the Jurassic and Cretaceous periods),two centers of ore formation emerged successively in the Narding region; the former is mainly for rare metals (W,Sn,Mo,Bi,Nb) and one rare earth element (La) and was generated in the Jurassic period; whereas the latter is mainly for base metals (Cu,Pb,Zn,Sb,Hg),noble metals (Au,Ag),and one radioactive element (U) and was generated in the Cretaceous period.Centers of ore formation were brought about by interface dynamics respectively at the Qitianling and Jiuyishan districts in southern Hunan Province.The characteristic giant nonlinear target pattern regional ore zonality was generated respectively from the two centers of ore formation by the spatio-temporal synchronization process of the Nanling complex metallogenic system.It induced the collective dynamics and cooperative behavior of the system and displayed the configuration of the regional ore zonality.Then dynamical clustering transformed the configuration into rudimentary ordered coherent structures.Phase dynamics eventually defined the spatio-temporal structures of the target-pattern regional ore zonality and determined their localization and distribution.The integral successive processes of synchronization-dynamical clustering-phase dynamics accomplished the regional ore zonality by way of "multiple field dynamics" of spatio-temporal superposition of multiple coupled pulsatory solitary wave trains of the zonal sequences of different ores.A new methodology for revealing regional ore zonality is developed,which will encourage further investigation of the formation of deep-seated ore resources and the onset of large-scale mineralization. 相似文献
169.
Trace Elements and Sr, Nd Isotope Geochemistry of the Lajimiao Norite-Gabbro from the North Qinling Belt 总被引:1,自引:0,他引:1
S.R.Hart 《《地质学报》英文版》1994,68(2)
The Lajimiao norite-gabbro complex, as a part of the ophiolites on the southern side of the North Qinling belt, consists of gabbro and norite-gabbro. They were derived from different magma series: the gabbro was derived from tholeiitic magma series with higher TiO2, REE abundance and Fe3+/Fe2+ ratio ; norite-gabbro was derived from calc-alkali magma series with lower TiO2, Fe3+/Fe2+ ratio and REE abundance and much lower HREE abundance, which suggests that the source of the norite-gabbro magma was deeper and controlled by eclogite facies. Geochemical characteristics of both plutonic rocks are similar to those of island-arc basalts, such as relatively high contents of Ba, Pb and Sr and relatively low contents of Nb, Zr and N j.The Sr, Nd isotopic characteristics of the Lajimiao norite-gabbro complex are similar to those of ophiolites. Its εNd values are constant, about+2; whereas εst values have wide variation from - 6.4 to +31.2 and positively correlate with Na2O, H2O+ and CO2 contents and the Fe3+/Fe 相似文献
170.
Structure,Timing, and Mechanism of the Pliocene and Late Miocene Uplift Process of the Ailao Shan-Diancang Shan,SE Tibet,China 总被引:2,自引:0,他引:2
The uplift of the Ailao Shan-Diancang Shan(ASDS) along the Ailao Shan-Red River(ASRR) shear zone is an important geological event in the southeastern margin of Qinghai-Tibet Plateau tectonic domain in the Late Cenozoic,and it preserves important information on the structures,exhumational history and tectonic evolution of the ASRR shear zone.The uplift structural mode and uplift timing of the ASDS is currently an important scientific topic for understanding the ASDS formation and late stage movements and evolution of the ASRR shear zone.The formation of the ASDS has been widely considered to be the consequence of the strike-slip movements of the ASRR shear zone.However,the shaping of geomorphic units is generally direct results of the latest tectonic activities.In this study,we investigated the timing and uplift structural mechanism of the ASDS and provided the following lines of supportive evidence.Firstly,the primary tectonic foliation of the ASDS shows significant characteristic variations,with steeply dipping tectonic foliation developed on the east side of the ASDS and the relatively horizontal foliation on the west side.Secondly,from northeast to southwest direction,the deformation and metamorphism gradually weakened and this zone can be further divided into three different metamorphic degree belts.Thirdly,the contact relationship between the ASDS and the Chuxiong basin-Erhai lake is a normal fault contact which can be found on the east side of the ASDS.40Ar/39 Argeochronology suggests that the Diancang Shan had experienced a fast cooling event during 3–4 Ma.The apatite fission track testing method gives the age of 6.6–10.7 Ma in the Diancang Shan and 4.6–8.4 Ma in the Ailao Shan,respectively.Therefore the uplift of the ASDS can be explained by tilted block mode in which the east side was uplifted much higher than the west side,and it is not main reason of the shearing movements of the ASRR shear zone.The most recent uplift stages of the ASDS happened in the Pliocene(3–4 Ma) and Late Miocene(6–10 Ma). 相似文献