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Differentiation of Natural and Irradiated Blue Topaz by Cathodoluminescence(CL) Properties

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地学前缘 2009年第S1期16卷 169-170页

作者： Ying Song~(1,2),Xinqiang Yuan~2 1.faculty of earth Resources,china university of geosciences(wuhan),wuhan 430074,china. 2.Gemmological Institute,china university of geosciences(wuhan),wuhan 430074,china

Blue colored topaz is one of the most recognized gemstones ***,it is rarely found in the field and the products have been made mostly in laboratory using gamma,neutron and electron irradiation or combinations of these *** of the blue color in topaz remains not well understood, largely due to a lack of nondestructive way in idnetifying the blue *** we report a compari-

关键词： cathodoluminescence natural blue topaz irradiated blue topaz

Peat molecular fossils recording paleoclimatic change and organism replacement

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Chinese science Bulletin 2001年第20期46卷 1749-1752页

作者： XIE Shucheng & R. P. Evershed1. faculty of earth science, china university of geosciences, wuhan 430074, china 2. School of Chemistry, university of Bristol, Bristol, BS8 1TS, UK Correspondence should be addressed to Xie Shucheng (e-mail: scxie@ ***) faculty of earth science China University of Geosciences Wuhan China School of Chemistry University of Bristol Bristol

The occurrence of the dominant C23 n-alkane derived from bryophyte was demonstrated to be related to the cold climate, based on the GC and GC/MS analyses on a 40-cm long peat core, in which this compound exponentially varies in abundance with the depth corresponding to the well-known second Little Ice Age. Both the variation of the chemical components of modern bryophyte resulted from climatic change and the ecological data about the biological growth influenced by climate shed light on the point that the variation of this compound in the peat was related to the cold climate. This was also evidenced by the previously-reported lacustrine data. In addition, the variations of the ratios of ketones/esters and C24 n-alkene/n-alkane (C24:1/024:0) display the trend identical with that of organisms, implicating the replacement between bryophyte and monocotyledon occurring in the peat core.

关键词： bryophyte molecular fossil n-alkane paleoclimate Little Ice Age peat lacustrine.

Silurian Seismites in Hanxia,Yumen,North Qilian Mountains,and Their Tectonic Significance

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Acta Geologica Sinica(English Edition) 2001年第4期75卷 385-390页

作者： DU Yuansheng, GONG Shuyun, HAN Xin, WANG Jiasheng, GU Songzhuand LIN Wenjiao faculty of earth sciences, china university of geosciences, wuhan 430074, Hubei faculty of earth sciences China University of Geosciences Wuhan 430074 Hubei [?]2Du Yuansheng Male born in 1958 graduated from wuhan College of Geology and obtained his Master's degree in 1989 and Ph. D degree in 1994. He is now a professor of china university of geosciences and engaged in sedimentology stratigraphy and geology of orogenic belts. Tel: (027) 87436249 Fax: (027) 87436247 E-mail: dxyyz@***

The Caledonian orogenic belt of the North Qilian Mountains is an intensely active structure belt. In the process of the Late Caledonian syn-orogeny, the North Qilian-Hexi Corridor area was situated on the tectonic background of a syn-orogenic basin. In response to the orogenic process of the North Qilian Mountains, typical earthquake event deposits—seismites of the Silurian were widely distributed around Hanxia of Yumen City, the Liyuan River of Sunan County and Biandukou of Minle County. In the Hanxia area, where seismites are typically developed, clastic deposits of tidal-flat facies are the background deposits of the Hanxia Formation. The earthquake event deposits are characterized by sandy mudstone veins, synsedimentary microfractures, micro-corrugated laminations and earthquake breccias, which in turn constitute complex seismites, featuring seismic corrugation, shattering and liquefied sandy mudstone veins, auto-clastic breccias and intraclastic parabreccias. The seismites and tidal flat deposits formed typical sequences of earthquake event deposits.

关键词： Gansu Province North Qilian orogenic belt Caledonian Stage Silurian seismites earthquake event deposits

Late Permian-Middle Triassic Sea Level Changes of Yangtze Platform

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Journal of earth science 1996年第1期15卷 101-104页

作者： Yin Hongfu Tong Jinnan (faculty of earth sciences, china university of geosciences, wuhan 430074)

This paper first introduces procedures leading to the establishment of Late Permian-Middle Triassic sea level change curve of Yangtze platform. Bathymetric curves extracted from curve of habitat types are first transformed to sea level curves stage by stage. Comparison between curves of Yangtze and the world reveals that because the Late Permian marine sequences are lacking in most parts of the world, the Late Permian to Griesbachian curve of Yangtze may serve as an important reference for further revision of the world curve. The Early-Middle Triassic short-term changes of Yangtze are briefly concordant with those of Haq's world curve, whereas their long-term changes are discordant. The latter, however, is representative of the East Asian regions affected by the Indosinian orogeny. Basically the third cycles of Yangtze and the world are only pertly concordant, and even in concordant cases their concrete boundaries are not coincident. This indicater that sea level changes are not strictly synchronous over the world. It seems that the 1st and 2nd cycles (supercycles and megacycles) may be world-wide, but not the 3rd cycles.

关键词： Permian Triassic sea level change bathmetric curve Yangtze region.

SHRIMP zircon U-Pb age and significance of Early Paleozoic volcanic rocks in East Kunlun orogenic belt, Qinghai Province, china

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science china earth sciences 2006年第1期49卷 88-96页

作者： ZHU Yunhai1, LIN Qixiang1, JIA Chunxing2 & WANG Guocan1 1.faculty of earth science, china university of geosciences, wuhan 430074, china 2.Regional Geological Survey Academy of Qinghai, Xining 800003, china 1. faculty of earth science China University of Geosciences Wuhan 430074 China 2. Regional Geological Survey Academy of Qinghai Xining 800003 China

Early Paleozoic volcanic rocks in Nuomuhong area occurred as basalt slice and meta-volcanic slice. SHRIMP zircon U-Pb dating of the basalt slice and the meta-volcanic slice show that the age of the basalt slice is 419±5 Ma, and that of the meta-volcanic slice is 401± 6 Ma. These ages directly testify that there existed Early Paleozoic ocean-continent transform in East Kunlun, the basalt slice was formed in an extensional mid-ocean ridge setting and the meta-volcanic rock slice was formed in an extrusion subduction and collision setting. The inherited zircon age of 1734 Ma in volcanic rocks reflects that the base of East Kunlun may be Middle Proterozoic.

关键词： volcanic rocks, SHRIMP zircon U-Pb age, Early Paleozoic, East Kunlun orogenic belt.

Huanggang Intrusive Complexin Northern Tongbai Area:Island-Arc Tectonic Environment and Its Geological Significance

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Journal of earth science 1998年第3期17卷 37-41页

作者： Zhang Li Zhang Hongfei faculty of earth sciences, china university of geosciences, wuhan 430074

The Huanggang intrusive complex in northern Tongbai area was formed in Early Paleozoic. It mainly consists of ultra basic, basic, intermediate and acid rocks, dominated by intermediate and basic rocks. The complex belongs to calc alkaline series. Geochemical characteristics of major and trace elements show that the complex was derived from the fractional crystallization of co source magma. It is suggested that the complex was formed in island arc tectonic environment and was closely related to the northward subduction of the Erlangping back arc basin. Thus, the subduction of the back arc basin can induce the island arc type magmatism similar to the one formed in the setting of ocean plate subduction.

关键词： Huanggang intrusive complex island arc tectonic environment geochemistry northern Tongbai area North Qinling.

Application of Wavelet Analysis toInterference Elimination for Geochemical Hydrocarbon Exploration

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Journal of earth science 2000年第1期19卷 91-93页

作者： Zhang Liuping Ruan Tianjian faculty of earth Resources, china university of geosciences, wuhan 430074

Interference in the data of geochemical hydrocarbon exploration is a large obstacle for anomaly recognition. The multiresolution analysis of wavelet analysis can extract the information at different scales so as to provide a powerful tool for information analysis and processing. Based on the analysis of the geometric nature of hydrocarbon anomalies and background, Mallat wavelet and symmetric border treatment are selected and data pre-processing (logarithm-normalization) is established. This approach provide good results in Shandong and Inner Mongolia, china. It is demonstrated that this approach overcome the disadvantage of backgound variation in the window (interference in window), used in moving average, frame filtering and spatial and scaling modeling methods.

关键词： geochemical exploration petroleum exploration interference elimination wavelet analysis data processing anomaly recognition.

Synthesis and photochromic properties of WO_3 powder induced by oxalic acid

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science china Chemistry 2009年第5期52卷 609-614页

作者： SHEN Yi1, ZHU Hua1, HUANG Rong1, ZHAO Li2 & YAN ShaNing1 1 faculty of Material science and Chemical Engineering, china university of geosciences, wuhan 430074, china 2 faculty of Materials science and Engineering, Hubei university, wuhan 430062, china 1. faculty of Material science and Chemical Engineering China University of Geosciences Wuhan 430074 China 2. faculty of Materials science and Engineering Hubei University Wuhan 430062 China

Tungsten trioxide powder with the novel morphology was prepared via the hydrothermal method with oxalic acid as the organic inducer, the structure and shape of which were detected by X-ray diffraction (XRD), scanning electron microscopy (SEM) and BET. Furthermore, photochromic properties of the as-prepared powder samples were tested by an ultraviolet-visible spectrophotometer combined with a color difference meter. The corresponding results indicated that the induced product was still hexagonal WO3, made up of regularly spindle particles with 200-300 nm in length and 30-50 nm in width. The ratio of the length and width was from 4 to 10. Moreover, the special morphology improved its absorptive capacity to the excitation light source, resulting in its high photochromic properties.

关键词： WO3 powder photochromism oxalic acid organic inducer

Experimental study of ore gabbro liquid immiscibility

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science china earth sciences 2005年第4期48卷 496-505页

作者： SANG Zunan1,2, XIA Bin1, ZHOU Yongsheng3 & JIN Zhenmin4 1. Guangzhou Institute of Geochemistry, Chinese Academy of sciences, Guangzhou 510640, china 2. wuhan university, wuhan 430072, china 3. Institute of Geology, china Seismological Bureau, Beijing 100029, china 4. faculty of earth sciences, china university of geosciences, wuhan 430074, china 1. Guangzhou Institute of Geochemistry Chinese Academy of Sciences 510640 Guangzhou China 2. wuhan university 430072 Wuhan China 3. Institute of Geology China Seismological Bureau 100029 Beijing China 4. faculty of earth sciences China University of Geosciences 430074 Wuhan China

In this paper, the authors present the results of a preliminary experimental study on partial melting of fine-grained gabbro, Panzhihua, Sichuan Province, china. Experiments were conducted under (confining) pressure ranging from 450 to 500 MPa and temperature of 900— 1200℃. The results show that the initial melt is distributed along grain boundaries and triple junctions. Liquid immiscibility phenomena are noted in the melt with two compositional different melt phases, i.e. matrix and sphere phases. The matrix phase is relatively rich in Si, Al and K, and is depleted in Mg, Fe, Ca, Na and Ti, whereas the sphere phase shows opposite trends. The calculation of the melt free energy indicates that the liquid immiscibility is governed by the rule of thermodynamics, as the liquid immiscibility would result in the decrease in free energy of the melt system. The field relationships suggest that the liquid immiscibility may have played an important role in the generation of ore magma of Panzhihua V-Ti magnetite ore deposit. This study thus provides experimental constraints on the mechanism of the formation of V-Ti magnetite deposite.

关键词： partial melting, experimental study, gabbro, liquid immiscibility, ore formation mechanism.