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Geochemical and isotopic imprints of hydrodynamic environments of fissure waters in crystalline rocks

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Chinese Science Bulletin 1997年第9期42卷 756-761页

作者： WANG Yanxin and Khaustov Alexander P.1. china university of {2., wuhan 43.074, china 2. Russian university of People’s Friendship, Moscow, Russia china university of {2. Wuhan China Russian university of People’s Friendship Moscow Russia

IN recent years,world-wide researches in relation to geologic disposal of nuclear wastes,ore-forming process modelling and ultradeep geologic drilling have been carried out in areas of crys-talline rocks,and,as a resu... 详细信息

关键词： crystalline rocks hydraulic continuity hydrochemistry isotopes.

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 {2., wuhan 43.074, china 2.Key Laboratory of Biogeology and Environmental Geology of Ministry of Education, china university of {2., wuhan 43.074, 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

Electron microscopy study of the sakhaite from endogenous borate deposit in Hunan, china

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Science china Earth Sciences 2004年第3期47卷 232-238页

作者： LIU Xiangwen1,2. YANG Guangming2. ZOU Huamin3, QU Jing1 & ZHAO Wenxia4 1. Graduate School, china university of {2., wuhan 43.074, china 2. Test Center, china university of {2., wuhan 43.074, china 3. Physics and Technology College, wuhan university, wuhan 430072. china 4. Test Center, Zhongshan university, Guangzhou 5102.5, china Graduate School China University of Geosciences Wuhan 430074 China Test Center China University of Geosciences Wuhan 430074 China Physics and Technology College Wuhan University Wuhan 430072 China Test Center Zhongshan University Guangzhou 510275 China

Sakhaite specimens from an endogenous borate deposit in Hunan Province, china have been studied in detail by means of transmission electron microscopy (TEM). The selected area electron diffraction (SAED) patterns obtained with different crystal zone axes show that the crystal system is cubic, with a = 1.463 nm. The convergent beam electron diffraction (CBED) patterns indicate that the point group and space group of sakhaite is m3m and Fd3m, respec-tively. The space group of synthetic sakhaite determined by Chichagov (1974) is F4132. The possible reasons why the space groups of the natural and the synthetic sakhaites are different are discussed.

关键词： sakhaite, space group, convergent beam electron diffraction (CBED).

Permian carbonates of Baoshan block, Western Yunnan and their paleoclimatic implications

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Science china Earth Sciences 2004年第5期47卷 385-392页

作者： YAN Jiaxin1, LIANG Dingyi1 & WU Ming2.1. Faculty of Earth Sciences, china university of {2., wuhan 43.074, china 2. College of Chemistry and Life Sciences, South-Central university for Nationalities, wuhan 43.074, china Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China College of Chemistry/Life Sciences South-Central Univ./Nationalities Wuhan 430074 China

Recently, much attention has been paid to the climatic significance of carbonates originating in shallow water. Permian carbonates of shallow shelf origin are present in the upper part of the Dingjiazhai Formation, the upper part of the Yongde Formation, and the Shazipo Formation on the Baoshan block of Western Yunnan. Their skeleton and non-skeleton grain as-sociations have been investigated in this study. The carbonates of the Dingjiazhai Formation indicate a Bryonoderm (bryozoans-echinoderm) association without non-skeleton grains. The carbonates of Yongde and Shazipo formations show Chloroforam (green algae-foraminifers) association with peloids. Oolites develop in the Shazipo Formation. Based on the comparisons of grain association with coeval carbonates formed in different paleolatitudes (i.e. various paleo-climatic zones), the carbonates of the Dingjiazhai Formation were thought to have been accu-mulated in shelf environments of warm-temperate zone, and those of the Yongde and Shazipo formations in shelf environments of warm-water.

关键词： Early Permian, carbonate, paleoclimate, Western Yunnan.

中国政治经济学年度发展报告（2.2.）（下）

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政治经济学评论 2024年第3期 90+207-208页

作者： Center for Studies of Contemporary Political Economy,Research Institute for 2.st-Century Marxism,Nankai university·university of Chinese Academy of Social Science Center for Teaching and Research on Capital,Renmin university of china National Institute of Socialist Political Economy with Chinese Characteristics,Renmin university of china 南开大学·中国社会科学院大学2.世纪马克思主义研究院当代政治经济学研究中心中国人民大学《资本论》教学与研究中心中国人民大学全国中国特色社会主义政治经济学研究中心

编者按2.2.年，高质量发展扎实推进，新质生产力加快形成，我国经济总体回升向好，圆满实现发展主要预期目标。为针对性地破解经济恢复发展中的难题，聚焦推进中国式现代化进程中的重点、难点问题，中国政治经济学界开展系统深入研究，...

编者按2.2.年，高质量发展扎实推进，新质生产力加快形成，我国经济总体回升向好，圆满实现发展主要预期目标。为针对性地破解经济恢复发展中的难题，聚焦推进中国式现代化进程中的重点、难点问题，中国政治经济学界开展系统深入研究，取得系列代表性成果。为准确刻画学界研究进展和轨迹，推动中国经济学理论体系的构建和完善，本刊精选议题如期奉上《中国政治经济学年度发展报告（2.2.）》。自2.10年起，本刊连续十四年发布《中国政治经济学年度发展报告》，“年度发展报告”专栏已成为本刊标志性特色栏目。2.2.年报告聚焦12.专题，分为（上）（下）两篇，其中专题1—6于报告（上）篇刊登，专题7—12.报告（下）篇刊登。2.2.年报告（下）选题如下：

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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 {2., wuhan, Hubei china university of {2. 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.

关键词： In

Seabed Classification Using BP Neural Network Based on GA

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Acta Oceanologica Sinica 2003年第4期22卷 523-531页

作者： Yang Fanlin1, Liu Jingnan2.1. GPS Engineering Research Center, wuhan university, wuhan 430079, china. 2. Presidential Secretariat, wuhan university, wuhan 430079, china GPS Engineering Research Center Wuhan University Wuhan 430079 China Presidential Secretariat Wuhan University Wuhan 430079 China

Side scan sonar imaging is one of the advanced methods for seabed study. In order to be utilized in other projects, such as ocean engineering, the image needs to be classified according to the distributions of different classes of seabed materials. In this paper, seabed image is classified according to BP neural network, and. Genetic Algorithm is adopted in train network in this paper. The feature vectors are average intensity, six statistics of texture and two dimensions of fractal. It considers not only the spatial correlation between different pixels, but also the terrain coarseness. The texture is denoted by the statistics of the co-occurrence matrix. Double Blanket algorithm is used to calculate dimension. Because a uniform fractal may not be sufficient to describe a seafloor, two dimensions are calculated respectively by the upper blanket and the lower blanket. However, in sonar image, fractal has directivity, i. e. there are different dimensions in different direction. Dimensions are different in acrosstrack and alongtrack, so the average of four directions is used to solve this problem. Finally, the real data verify the algorithm. In this paper, one hidden layer including six nodes is adopted. The BP network is rapidly and accurately convergent through GA. Correct classification rate is 92.5 % in the result.

关键词： BP network co-occurrence matrix fractal classification genetic algorithin

Lithospheric seismic fabrics of Sulu ultrahigh-pressure metamorphic belt

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Science china Earth Sciences 2005年第5期48卷 585-600页

作者： YANG Wencai 1 , YANG Wuyang 1 , JIN Zhenmin 2.& CHENG Zhenyan 1 1. Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, china 2. china university of geosciences,{2., china Chinese Academy of Geological Sciences Institute of Geology Beijing China china university of {2. Wuhan China

Calibration of seismic reflectors appearing in the crust of the Chinese continent sci- entific drilling site can be completed through the correlation studies between direct evidences, such as the drill cores, and geophysical signatures; therefore the interpretation of geophysical data could produce reliable results of crustal structure and composition. On the other hand, there are two Cenozoic volcanoes close to the scientific drilling site; analyzing composition of xenoliths existent in the volcanoes and evaluating their seismic velocities can also offer information about the mantle and lower crust. After the calibration via cores and well-logging data, the seismic re- flectors appearing in the UHP belt can be caused by lithological changes within the UHP rock slice, ductile shearing rock-suites, and later fracture zones. Among these sources, ductile shearing resulted in displacement and detachment of original rock-sheets, producing some rock-interbeds of several hundred meters thick that are named the ductile shearing rock-suites. A suite consists of mylonized gneiss and eclogite slices that underwent shearing, becoming the major mechanism responsible to generate regional strong reflections. The UHP rock-slice is characterized by complicated structures and high density, high seismic velocity and high electri- cal resistivity, its thickness is usually less than 11 km. Velocity and density of the gneiss-layer beneath gradually tend to normal with increasing depth. Based on the xenoliths we can infer that the middle crust contains a lot of gneisses, and the lower crust consists of different granulites. The lithospheric mantle has multi-layer structures and consists mainly of spinal lherzolite and harzburgite, implying late Mesozoic lithospheric thinning. The seismic fabrics with different ori- gins were possible products of different geodynamic processes. For instance, the UHP rock-slice was produced by the UHP metamorphic process and the exhumation of subducted supe

关键词： deep seismic reflection, ultrahigh-pressure belt, Sulu china, calibration of reflectors, lithospheric fabrics.

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 {2., wuhan, Hubei Liu Linqun china university of {2. 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