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Tectonic Factors Favourable for the Formation of Evaporites in the Indosinian Period in Hubei and Its Neighbouring Areas

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Acta Geologica Sinica(English Edition) 1988年第4期1卷 381-391页

作者： Li Shiruo china university of geosciences, wuhan, Hubei china university of geosciences Wuhan Hubei

In the Indosinian period. the climate was scorching hot and the source of seawater was ample in Hubeiand its neighbouring areas. so the basic conditions for the formation of evaporites were favourable. Under thisprerequisite. the reason why salt deposits occurring in some third-order tectonic units between the Jiangnanoldland-upwarped zone and the Dabashan upwarped zone differ in degree of development is mainly due to thetectonic factors during sedimentation. If favourable tectonic factors are present, large amounts or evaporiteswill form: on the contrary. they will not.

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Middle and Late Carboniferous Tetracoral Assemblages and Biogeography of china

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Acta Geologica Sinica(English Edition) 1989年第2期63卷 103-114页

作者： Wang Zhiping china university of geosciences, wuhan, Hubei Liu Linqun china university of geosciences Wuhan Hubei

china is rich in Middle and Carboniferous fossil corals. The coral faunas in different regions have varying characteristics and can be divided into distinct assemblages. The coral fauna in South china is dominated by the order Caninida and contains numerous endemic elements; that in North china has a lot of Middle Carboniferous corals which are monotonous in species, with Late Carboniferous solitary corals being predominant. The coral fauna in Junggar mainly contains large bi-zoned solitary caninids, while that in southern Khingan is similar to that in South china due to the presence of abundant tri-zoned compound corals. In northern Tibet the coral fauna is also similar to that in South china, but in southern Tibet it is of a cold-water type. Therefore, the Middle and Late Carboniferous coral geography of china can be divided into the Tethys, Boreal and Gondwana Realms.

关键词： La Middle and Late Carboniferous Tetracoral Assemblages and Biogeography of china

The Magma-dynamic Mechaism of Emplacement and Compositional Zonation of the Zhoukoudian Stock, Beijing

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Acta Geologica Sinica(English Edition) 1989年第2期63卷 159-173,210-211页

作者： Ma Changqian china university of geosciences, wuhan, Hubei china university of geosciences Wuhan Hubei

The Zhoukoudian stock in Beijing is a concentric zoned complex intrusive body formed by two successive intrusions. Quartz-diorite formed by the first intrusion is scattered sparsely on the margins of the body, while granodiorite resulting from the second intrusion constitutes the main part of the intrusion. It exhibits three distinct petrographic zones macroscopically, and is chemically characterized by enrichment of high-temperature components, such as Mg, Ca, Sc, Ti, Cr, Mn. Fe and Co, on its border and merely slight enrichment of some low-temperature components, such as Na and Si, in its central part. A series of structural features indicate that the deformation of the intrusion and thermo-metamorphic rocks becomes weaker with an increase of distance from the contact, and that the intrusive body is a product of ballooning or inflating diapiric emplacement. Based on calculations of the density, viscosity and yield strength of magma and the reasonable diffusion constants and oxygen isotopic data, the mechanism of the compositional zonation of the major part of the stock is discussed. It is considered that the Soret effect, combined with double-diffusive convection, can explain the compositional zonation of the intrusion. Calculation of the ascent rates of magma shows that successive upwelling of magma got faster and faster with the progress of time.

关键词： The Magma-dynamic Mechaism of Emplacement and Compositional Zonation of the Zhoukoudian Stock Beijing

Mechanical Research on Biucleus-Type Vortex Structures

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Acta Geologica Sinica(English Edition) 1990年第4期64卷 345-362,462页

作者： Zeng Zuoxun Section of Geomechanics, china university of geosciences, wuhan, Hubei Fei Zhenbi Section of Geomechanics China University of Geosciences Wuhan Hubei

A new type of vortex structure-binucleus-type vortex structure-is presented in this paper. It is charac-terized by two nuclear columns which distinguish it from uninuclcus-type vorlex structure. The vortical sur-faces of the structure are commonly s-shaped and reversed s-shaped and subordinately of clliptic andhyperbolic shape. and sometimes turbine-like surfaces are observed. On the basis of field structural studies. a mechanical model of rotation around a binuclear column ofcrustal materials is presented in the paper. Burgers viscoelastic solutions of the stress field and deformationfield of this structural type have been obtained using the principle and method of rheology. and simulation ex-periments have been performed. The results of the theoretical calculation and experiments indicate that theproposed mechanical model is applicable.

关键词： Mechanical Research on Biucleus-Type Vortex Structures

Evolutionary patterns of Productida (Brachiopoda) morphology during the Permian in South china

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Science china Earth Sciences 2008年第11期51卷 1589-1600页

作者： ZHANG Yang1 & HE WeiHong1,2 1 Faculty of Earth Sciences, china university of geosciences, wuhan 4.0074. china 2 Key Laboratory of Biogeology and Environmental Geology of Ministry of Education, china university of geosciences, wuhan 4.0074. china Faculty of Earth Sciences China University of Geosciences Wuhan China Key Laboratory of Biogeology and Environmental Geology of Ministry of Education China University of Geosciences Wuhan China

The evolutionary patterns of Productida (brachiopod) morphology throughout the Permian show that while the percentage proportion of Productida (brachiopod) with strongly concentric and radial ornamentation declined from the Cisuralian to the Guadalupian, and then increased towards the Changhsingian via Wuchiapingian, the percentage proportion of Productida (brachiopod) with fine concentric and radial ornamentation distinctly increased from the Cisuralian to the Guadalupian, slightly declined towards the Wuchiapingian, and then increased towards the Changhsingian. From the Cisuralian to the Changhsingian, the percentage proportion of brachiopods with spinose ornamentation shows a persistent declining trend. The shell size generally indicates a miniaturization trend at species level during the Wuchiapingian to Changhsingian (including the transitional bed). These evolutionary patterns of brachiopod ornamentation and size are possibly related to the anoxia, food shortage, sea-level fluctuation, and change of substrate in the Permian (including the Permian-Triassic transitional interval) in South china.

关键词： brachiopod ornamentation size Permian South china

Exsolution of ilmenite and Cr-Ti magnetite from olivine of garnet-wehrlite

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Science china Earth Sciences 2005年第9期48卷 1368-1376页

作者： LIU Xiangwen1,2, JIN Zhenmin1,3, QU Jing2 & WANG Lu2 1. State Key Laboratory of Geological Processes and Mineral Resources, china university of geosciences, wuhan 4.0074. china 2. Graduate School of china university of geosciences, wuhan 4.0074. china 3. Faculty of Earth Sciences, china university of geosciences, wuhan 4.0074. china State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan China Graduate School of china university of geosciences Wuhan China Faculty of Earth Sciences China University of Geosciences Wuhan China

Exsolution of rod-like ilmenite (Ilm) and Cr-Ti magnetite (Mt) have been found in olivine of garnet-wehrlite from the core of Chinese Continental Sciences Drilling (CCSD). Their composition, morphology, crystal structure and their topotaxies with host olivine have been studied in detail by the transmission electron microscopy (TEM) and electron probe microanaly- sis (EPMA) technique. It shows that rod-like Ilm exsolution reported in this paper has similar characteristic with that of Alpe Arami olivine, while Cr-Ti magnetite exsolution mentioned in this paper has large discrepancy with chromite exsolution in Alpe Arami olivine. These observations suggest that both of the exsolutions found in this paper should be solid solution phases in β-olivine at their first period, then experiencing decomposition of solid solution and therefore forming Ilm and Cr-Ti magnetite exsolution with the pressure decreasing. So, this garnet-wehrlite perhaps had been ever located in mantle transition zone with a minimum depth of 300 km.

关键词： garnet-wehrlite, ilmenite, magnetite, exsolution, CCSD.

Petrological Study on the Ductile Shear Zones in the Core of the Eastern Qinling Orogenic Belt in Western Henan

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Acta Geologica Sinica(English Edition) 1990年第4期64卷 379-391,463页

作者： Zhong Zengqiu You Zhendong Suo Shutian china university of geosciences, wuhan, Hubei Jiang Minxi china university of geosciences Wuhan Hubei

A series of ductile shear zones of the overthrust and strike-slip-types and related ductile shear metamorphicrocks, including tectonic melange and mylonites. were formed in the core of the Qinling orogenic belt in thecourse of the Caledonian-Indosinian ductilc and brittle-ductile reworking. The study on their petrography. va-riations in composition and conditions of formation is conducive to revealing the metamorphism-deformationhistory of the core of the Qinling orogenic belt and further to understanding the dynamic mechanism of its evo-lution.

关键词： Petrological Study on the Ductile Shear Zones in the Core of the Eastern Qinling Orogenic Belt in Western Henan Core

Cretaceous-Early Eocene Tectonic Stress Field in china

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Acta Geologica Sinica(English Edition) 1989年第3期63卷 227-239页

作者： Wan Tianfeng and Zhu Hong china university of geosciences, Beijing, china 2Wan Tianfeng male born in 1938 engaged in geological education since 1959 and now is a professor of the Teaching and Research Group of Structural Geology China University of Geosciences Beijing 100083. china university of geosciences Beijing China

The Cretaceous-early Eocene tectonic stress field in china was reconstructed using the data of 36. largeand medium-scale flexural folds and 157 joint sets. It was found that the maximum compressive principal stress axis in eastern china dips 32° NE (nearly horizontal), and strikes SW 212°, whereas that in western china dips 15° NE (also nearly horizontal) and trends SW 195°. The estimation of the dip angles of fold limbs and the palaeotectonic stress values indicates that there was a tendency of gradual weakening of tectonism from southwestern to northeastern china in the Cretaceous-early Eocene. At the depth of 2-3 km, the differential stress value changes from 183 MPa in Tibet to 100 MPa in North and East china.The authors consider that the tectonic stress of this period was related to the north-northeastward movement and push of the Indian-Australian plate.

关键词： Cretaceous-Early Eocene Tectonic Stress Field in china

Analytical method of Cr stable isotope and its application to water pollution survey

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Chinese Science Bulletin 2010年第7期55卷 664-669页

作者： GAO YongJuan 1,2,3,MA Teng 4,5,LING WenLi 1,2,LIU CunFu 4,5 & LI Li 4,5 1Faculty of Earth Science,china university of geosciences,wuhan 4.0074.china 2State Key Laboratory of Geological Processes and Mineral Resources,china university of geosciences,wuhan 4.0074.china 3 Graduate School,china university of geosciences,wuhan 4.0074.china 4 Biogeological and Environmental Geology Laboratory of Ministry of Education(china university of geosciences) ,wuhan 4.0074.china 5 Sino-Hungary Joint Laboratory of Environmental Sciences and Health,china university of geosciences,wuhan 4.0074.china Faculty of Earth Science China University of Geosciences Wuhan 430074 China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China Graduate School China University of Geosciences Wuhan 430074 China Biogeological and Environmental Geology Laboratory of Ministry of Education (china university of geosciences) Wuhan 430074 China Sino-Hungary Joint Laboratory of Environmental Sciences and Health China University of Geosciences Wuhan 430074 China

High Cr(VI) concentration is a potential serious risk to environment and ecologic ***,it is essential to effectively monitor Cr contamination in water systems and scientifically evaluate its evolution trend.A new method of in-situ tracer technique by Cr isotopic analysis for quantitatively estimating Cr-contamination and its regional evolution in natural waters as well as a case application are reported in this *** on documented literatures,an experimental procedure for chemical separation and purification of Cr in water samples and its analytical method for Cr isotopic measurement by thermal ionization mass spectrometry(TIMS) are *** samples collected around a chemical factory in Hubei Province were analyzed by this *** samples showδ53Cr values ranging from-1.7‰to 7.3‰and an elevating trend with an increasing in distance from the sampling site to pollution source.A functional correlation following Rayleigh fractionation law was established between sample'sδ53Cr value and its extent of Cr *** study suggests that Cr isotopic analysis is an effective method to reveal the spatial distribution and its evolution trend of Cr contamination in the regional water *** is thus helpful to assessing the self-purifying ability of local water system according to Cr isotopic fractionation.

关键词：铬(VI) 水污染调查稳定同位素应用同位素分析供水系统演变趋势示踪技术