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Impact of changing atmospheric CO_2.concentrations over the Phanerozoic on stomatal parameters of vascular land plants

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chinese Science Bulletin 1999年第7期44卷 577-582页

作者： SUN Qigao, CHEN Liqun and LI Chengseninstitute of Botany, chinese {2. of sciences, beijing 100093, china, institute of Botany Chinese Academy of Sciences Beijiing China

A novel and multi-disciplinary subject involving the relationships between changes in atmospheric CO2.concentration throughout the geological history and features of plant anatomy is reviewed. Particular attention wil... 详细信息

A novel and multi-disciplinary subject involving the relationships between changes in atmospheric CO2./sub> concentration throughout the geological history and features of plant anatomy is reviewed. Particular attention will be given to stomatal parameters （stomatal density and stomatal index） which are recorded at a cellular level in fossil plants and the relationships of these observable parameters to earth life history and global environmental change. Trends of atmospheric CO2./sub> concentrations during the Phanerozoic period are briefly introduced and recent conceptual advances in understanding the causal mechanisms for changes in stomatal parameters of land vascular plants are considered, In addition, some of the inherent problems and limitations of this kind of work are discussed and future research directions are presented.

关键词： Phanerozoic atmospheric CO2 concentrations vascular plants stomatal parameters.

On the Post-Variscan Global Tectonic Stages

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Acta Geologica Sinica(English Edition) 1987年第1期 23-35页

作者： Ren Jishun institute of geology,{2., beijing

After the Variscan Cycle, the global tectonic framework underwent three major adjustments. The first occurred in the Late Triassic-initial Jurassic, the second in the Late Jurassic-early Early Cretaceous and the third in the Late Cretaceous-Eogene. On that basis, the post-Variscan tectonic history is divided into three tectonic cycles——the Indosinian, Yanshanian and Himalayan Cycles. The post-Neocom（k;） andpre-Aptian（k;） tectonic movement marks the end of the Yanshanian orogeny in eastern china and the initiation of the subduction of the Tethyan ocean in western china and represents the boundary between the Yanshanian and Himalayan Tectonic Cycles.

关键词： On the Post-Variscan Global Tectonic Stages

The Existence of the Negative Charge of Gold in Sulphide Minerals and Its Formation Mechanism

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Acta Geologica Sinica(English Edition) 1995年第3期69卷 303-315,341页

作者： Li Jiuling, Feng Daming, Qi Feng and Zhang Guilan institute of Mineral Deposits, chinese academy of geological sciences, {2. {2. U niversity of Science and Engineering, {2. Fei Zhenbi 1 institute of Mineral Deposits Chinese Academy of Geological Sciences Beijing2 Beijing University of Science and Engineering Beijing

Through a study, particularly an X-ray photoelectron spectroscopy (XPS or ESCA) analysis, of gold-bearing arsenopyrite and pyrite in Carlin-type gold deposits of Guangxi, china, and hydrothermally synthesized gold-bearing pyrite and marcasite, the authors have found that these minerals contain 'invisible gold' whose binding energy is lower than that of native gold (Au°). Therefore they suggest that gold occurs in a negative charge state in these sulphide minerals as it replaces some sulphur and is combined with sulphur with the covalent bond. This paper also preliminarily discusses the possibility of its formation from the chemistry and geochemistry of gold, crystal chemistry of arsenopyrite, pyrite and marcasite and geochemical environment.

关键词： Carlin-type gold deposit sulphide invisible gold chemical bound gold negative charge of gold

The Igneous Rock Series and Tin Polymetailic Minerogenetic Series in the Tengchong Area, Yunnan

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Acta Geologica Sinica(English Edition) 1989年第2期63卷 175-187页

作者： Mao Jingwen institute of Mineral Deposits, chinese academy of geological sciences, {2. Fei Zhenbi

This paper discusses the late Yanshanian-Himalayan igneous rock series and minerogenetic series (Cheng et al., 1979, 1982. related to tin polymetallic deposits in the Tengchong area. The multi-stage differentiation and evolution of the igneous rock series led to the concentration of metal and ore-forming elements in a cupola of a granite body formed in the late stage. The minerogenetic series shows a zoning of Nb-Ta-W-Sn, Sn-Fe and Sn around the cupola in space and a multi-stage regularity in time. Finally a minerogenetic model and three key factors of tin minerogenesis are put forward for tin polymetallic deposits in the area.

关键词： The Igneous Rock Series and Tin Polymetailic Minerogenetic Series in the Tengchong Area Yunnan

Phosphatized embryo fossils from the Cambrian explosion

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chinese Science Bulletin 1999年第9期44卷 842-845页

作者： YUE Zhao and Stefan Bengtsoninstitute of geology ,{2. , beijing 10003. , china Department of Palaeozoology , Swedish Museum of Natural History , Box 50007 , S-104 05 , Stockholm , Sweden institute of geology Chinese Academy of Geulogical Sciences Beijing China Department of Palaeozoology Swedish Museun of Natuol History Stockholm Sweden

The earliest Cambrian (Meishucunian) phosphatized metazoan Olivooides from the Yangtze platform is represented by different developmental stages: from blastula through possible gastrula to tissue differentiation and finally to the hatched animals. The fossilization of embryos opens a new field in palaeontology-palaeoembryology. Embryological studies will be of importance for the understanding of ontogeny and phylogeny of metazoans from the Cambrian explosion.

关键词： embryo Early Cambrian Olivooides phosphatization.

Zircon shrimp U-Pb geochronology and petrogenesis of the plagiogranites from the Lagkor Lake ophiolite,Gerze,Tibet,china

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chinese Science Bulletin 2007年第5期52卷 651-659页

作者： ZHANG YuXiu1,2. ZHANG KaiJun1,3, LI Bing1,2. WANG Yang1,2. WEI QingGuo1,2.& TANG XianChun1,2.1 Key Laboratory of Marginal Sea geology, Guangzhou institute of Geochemistry, {2. academy of sciences, Guangzhou 510640, china 2.Graduate University, {2. academy of sciences, beijing 10003., china 3 Department of Earth sciences, Nanjing University, Nanjing 2.0093, china Key Laboratory of Marginal Sea geology Guangzhou Institute of GeochemistryChinese Academy of Sciences Guangzhou 510640 China

地关系与 petrographical 一起， petrological ，和 geochemicalcharacteristics ，和锆石人口，显示从在 Bangong-Nujiang 缝术地区的 Lagkor Lakeophiolite 的 plagiogranites (～ Gerze 县的 2. km 南方，中央西藏，中国)，由在海洋的外壳的运输期间的可锻的砍源于含水的斑粝岩的 anatexis 。因此，这种 plagiogranite 比传播海洋的外壳晚对或很少同时代。锆石虾 166 ±使 2.5 妈变老因为 plagiogranites 显示海洋的盆在中间的侏罗记在 Bangong-Nujiang 地区的西方的部分存在。

关键词：西藏改则县拉果错湖泊蛇绿岩斜长花岗岩锆shrimp U-Pb地质年代岩石成因

Rheological Simulating Study of Mechanical Conditions for Syn-extensional Basin and Mountain Coupling System

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Journal of china University of Geosciences 2003年第4期14卷 330-338页

作者： Wu Hongling Yin Xiulan institute of Geomechanics, chinese academy of geological sciences, {2. 100081 institute of Geomechanics Chinese Academy of Geological Sciences Beijing 100081

This article gives a mechanical model, in which the layers of lithosphere are assumed to be the creep materials, to study the coupling mechanism of a syn-basin-mountain system quantitatively by using the numerical simulating method. A geological dynamic extensional mode given by some geologists is theoretically discussed and verified. The study shows that lithosphere thickening or thinning is closely related to the thermal activity, or in other words, thermal convection beneath the lithosphere. It is one of the important factors affecting the formation of the basin-mountain coupling system. As an essential condition, only the upward buoyant force and the horizontal dragging force caused by the thermal convection jointly act on the bottom of the lithosphere, the stress and strain states in rock's layers are advantageous to forming the tectonic-landforms of the basin-mountain coupling system. A study on the creep features of the lithosphere shows that the stress and strain in the rock's layers vary with time when the lasting forces act on the boundary. They increase rapidly at initial stage and decrease steadily after reaching the peak value. Phenomena of stress relaxation are significant for studying the tectonic evolution.

关键词： lithosphere thinning basin-mountain system dynamic mechanism creep numerical simulating method.

On three-dimensional geological modeling and visualization

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Science china Earth sciences 2004年第8期47卷 739-748页

作者： WU Qiang1 & XU Hua2.1. Department of Resource Exploitation Engineering, china University of Mining and Technology, beijing 100083, china 2. beijing institute of Petrochemical Technology, beijing 102.17, china 1. Department of Resource Exploitation Engineering China University of Mining and Technology 100083 Beijing China 2. beijing institute of Petrochemical Technology 102617 Beijing China

The technology of 3D geological modeling will bring about great changes in the methods of geological data acquiring, storing, processing and displaying. However, no perfect or convenient software systems have been developed up to now since the geologic data which re-flect geological entities bear the feature of diversity, uncertainty and complexity. Some supervoxel models, mathematical models of fault and geometrical models of fold have been contrived so as to show the space geometric configuration of the complicated geologic structures. The application-oriented system architecture for 3D geological modeling is established; and a novel design concept based on spatial data processing is also proposed with the technology of solid modeling as its core and the application of models as its objective. Theories and methods for 3D geological modeling will hopefully be enriched and developed. In the light of these theories and methods, a feature-based navigation visualization technique is also put forward in the paper. By integrating geo-database, graphics libraries and KBS with 3D dynamic simulation systems, geologists will be able to capture the partial characteristics and whole structure embodied in the geological data in a direct-viewing, figurative and accurate manner.

关键词： 3D geological modeling,geometrical model,system architecture,visualization

Neoproterozoic zircon inheritance in eastern North china craton(china) Mesozoic igneous rocks:derivation from the Yangtze craton and tectonic implications

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Neoproterozoic zircon inheritance in eastern North China cra...