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Quantitative assessment of the complexity of geological structures in terms of seismic propagators

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Science china Earth sciences 2010年第1期53卷 54-63页

作者： FU LiYun Key Laboratory of the Earth’s Deep Interior,institute of geology and Geophysics,{2. academy of sciences,beijing 10002.,china 1. Key Laboratory of the Earth’s Deep Interior Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

How a wave interacts with heterogeneous media has been pursued by many *** complexity of subsurface heterogeneities is seismologically a relative concept to wavelengths of seismic waves.A growing perception is that velocity variations,propagation angles,and computational accuracies are closely related at a variety of scales.A tentative strategy to quantitatively evaluate the complexity of subsurface heterogeneous media is presented in this article to see what scales of geological heterogeneities to be captured by *** express complex subsurface structures as the slowness-and angularheterogeneity spectra to quantify velocity contrasts and dipping-angle distributions of complex geological *** the other hand,the scaling characteristics of a propagator are measured through dispersion analysis by its angular spectra plotted against refractive indexes and propagation angles,respectively.A parameter termed as imaging efficiency is introduced by associating the geological heterogeneity spectra with the propagator's angular spectra to understand the coherent interference between the medium's heterogeneity and the propagator's scaling ***,a complexity coefficient can be defined to evaluate geological complexities in terms of *** application of this strategy is demonstrated to the SEG/EAEG salt model.

关键词： geological heterogeneity spectra seismic imaging propagator’s angular spectra imaging efficiency complexity coefficient

^(14)C measurement of forest soils in Dinghushan Biosphere Reserve

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chinese Science Bulletin 1999年第3期44卷 251-256页

作者： SHEN Chengde , LIU Dongsheng (LIU Tungsheng) , PENG Shaolin, SUN Yanmin , JIANG Mantao , Yl Weixi , XING Changping , GAO Quanzhou , LI Zhi’an and ZHOU Guoyi Guangzhou institute of Geochemisry, chinese {2. of sciences, Guangzhou 510640, china institute of geology, chinese {2. of sciences , beijing 10002., china South china institute of Botany, chinese {2. of sciences, Guangzhou 510650, china Guannzhou institute of Geochemisry Chinese Academy of Sciences Guanazhou China institute of geology Chinese Academy of Sciences Beijing China South china institute of Botany Chinese Academy of Sciences Guangzhou China

Organic carbon in forest soils of Qingyunsi and Wukesong profiles can be divided into fast and slow components. Δ14C values of these profiles decrease with increasing of depth. The Δ14C values in 30—40 cm depth interval of Wukesong profile are decreasing sharply until a very low value,showing that a strong geological environment change occurred about 1 560 years ago. The 14C apparent ages of Wukesong profile show that the coniferous and broad-leaf mixed forests around Wukesong profile have been developing since 42. a BP, which is consistent with historical documents. The penetrating depths of "bomb 14C" in Qingyunsi and Wukesong profiles are 10 and 2. cm, respectively.

关键词： Dinghushan forest soil 14C tracing 14C apparent age.

The crystal structure of (Fe_(4)Cr_(4)Ni)_(9)C_(4)

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Science china Earth sciences 2005年第3期48卷 338-345页

作者： SHI Nicheng1, MA Zhesheng1, XIONG Ming1, DAI Mingquan1, BAI Wenji2. FANG Qingsong2. YAN Binggang2.& YANG Jingsui2.1. X-ray Diffraction Laboratory, china University of Geosciences, {2. 100083, china 2. institute of geology, chinese academy of geological sciences, beijing 1.0037, china 1. X-ray Diffraction Laboratory China University of Geosciences 100083 Beijing China 2. institute of geology Chinese Academy of Geological Sciences 100037 Beijing China

(Fe4Cr4Ni)9C4 is a metal carbide mineral formed by combination of Fe, Cr and Ni with C. It occurs in a chromite deposit in the Luobusha ophiolite, Tibet. Based on the determina- tion of its crystal structure, the empirical formula is (Fe4.12.r3.84Ni0.96)8.92.3.70 and the simplified formula is (Fe4Cr4Ni)4C9. The mineral is hexagonal with a = 1.38392.2. nm, c = 0.44690(9) nm, space group P63 m c, Z=6 and the calculated specific gravity Dx = 7.089 g/cm3. Fe, Cr and Ni occupy different crystallographic sites and their coordination numbers are approximately 12. forming an alternate stacking sequence of flat and puckered layers along the c axis. Some me- tallic atoms have a defect structure. The interatomic distances of Fe, Cr and Ni are 0.2.2.— 0.2.66 nm, and the distances between Fe, Cr, Ni and C are 0.1893—0.2.69 nm. The coordina- tion number of carbon is 6. It occurs in interstices of the metallic atoms Fe, Cr and Ni to form trigonal-prismatically coordinated polyhedra. These coordination polyhedra are linked with each other via shared corners or shared edges into a new type of metal carbide structure.

关键词： Luobusha of Tibet, metal carbide, crystal structure.

Discovery of a pterodactylid pterosaur from the Yixian Formation of western Liaoning,china

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chinese Science Bulletin 2001年第13期46卷 1112-1117页

作者： WANG Xiaolin & LU Junchang1. institute of Vertebrate Paleontology and Paleoanthropology, chinese {2. of sciences, beijing 100044, china 2. College of Earth sciences and Resources, china University of Geo-sciences, beijing 100083, china 3. Department of geological sciences, Southern Methodist University, Dallas, TX 752.5, USA institute of Vertebrate Paleontology Chinese Academy of Sciences Beijing 100044 China

A well-preserved pterosaur with nearly complete skull is described from the Lower Cretaceous Yixian Formation at Sihetun in western Liaoning. It is characterized by a low and long crestless skull, slender and pointed teeth, long metacarpal, nearly equal length of metatarsals I -III and short pedal digit V. It is referred to a new genus and species of the family Pterodactylidae: Haopterus gracilis gen. et sp. nov. This is the first pterosaur with a nearly complete skull from the Jehol Biota; it also represents the first non-controversial fossil record of Pterodactylidae in Asia. Haopterus is more derived than Pterodactylus from the Late Jurassic Solnhofen in Germany. This discovery extends the distribution of the family Pterodactylidae from Europe and Africa to Asia and its latest occurrence from the Late Jurassic to the Early Cretaceous. The discovery of Haopterus gracilis provides further evidence for the study of the originand radiation of the Jehol Biota; it also sheds new light on the evolution and

关键词： western Liaoning Early Cretaceous Yixian Formation Pterodactylidae.

Kaolin Deposits of Weathering-Residual in the Coastal Area of Guangdong Province

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Acta Geologica Sinica(English Edition) 1991年第3期65卷 289-305,340页

作者： Zhou Guoping Lin Yuchuan institute of Mineral Deposits, chinese academy of geological sciences, {2.,Center of geological Analysis of Guangdong Province, Guangzhou institute of Mineral Deposits Chinese Academy of Geological Sciences Beijing China

Kaolin deposits of weathering-residual type make up a large proportion in different types of kaolin depos-its and are widely used in ceramics, electron ceramics, rubber and paper industries. This paper discusses sys-tematically this type of kaolin deposit with respect to their features of occurrence, mineralogical and chemicalcomposition and transformation of minerals during supergene processes, thus providing some basic data forthe rational exploitation and utilization of the kaolin resources.

关键词： Kaolin Deposits of Weathering-Residual in the Coastal Area of Guangdong Province

geological analysis and physical modeling of structural pumping in high effective formation of Kela 2.gas field

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Science china Earth sciences 2006年第10期49卷 1070-1078页

作者： ZHAO Wenzhi1, WANG Hongjun1, SHAN Jiazeng2. WANG Zecheng1 & XU Dafeng1 1. Research institute of Petroleum Exploration and Development, Petrochina, {2. 100083, china 2. institute of geology and Geophysics, chinese academy of sciences, {2. 10002., china 1. Research institute of Petroleum Exploration and Development Petrochina Beijing 100083 China 2. institute of geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

In a 3-D closed geological body, in case “structural expanding” inside is induced by stress, it can produce the pressure difference between the expanding cell and surrounding rock, then generate a pumping force directed toward the cell and accelerate the directional flow of fluid in the strata. The structural style and conditions of gas reservoir-formation in the Kuqa depression are favorable to the structural pumping. According to similarity principle, a physical modeling of structure formation and gas filling process of the Kela 2.gas field has justified the occurrence of structural pumping and its important role in gas-reservoir formation with high efficiency under the compressive and well-sealed circumstance. Therefore, authors propose that structural pumping is an important mechanism of gas reservoir-formation with high efficiency in the Kuqa depression.

关键词： Kela 2 gas field, structural pumping, gas-reservoir formation mechanism, high efficiency,physical modeling.

Underplating in the middle-lower Yangtze Valley and model of geodynamic evolution:Constraints from geophysical data

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Science china Earth sciences 2005年第7期48卷 985-999页

作者： Lü Qingtian, HOU Zengqian, YANG Zhusen & SHI Danian institute of Mineral Resources,chinese {2. of geological sciences,beijing 1.0037,china institute of Mineral Resources Chinese Academy of Geoloqical Sciences Beijina 100037 China

The lower crust and Moho are the most active boundary layers in the process of continental evolution, in which marks left by tectonic and magmatic activities during the process are preserved. The evolutionary process of the continental lithosphere may be reconstructed by exploring the structures of the lower crust and Moho. According to a study of the deep seismic reflection data obtained from the middle-lower Yangtze Valley, the authors find bright layered reflections ubiquitous in the lower crust and think that the bright reflections are caused by un-derplating of basic or ultrabasic magmas, which might be related to delamination of the lithosphere. On the basis of an integrated analysis of the geophysical and geological data of the region, the authors propose a model for geodynamic evolution of the middle-lower Yangtze Valley. This model suggests that the middle-lower Yangtze Valley had undergone such geodynamic processes as collision-compression, delamination-extension and underplating-melting since the end of the Permian, finally forming the gigantic middle-lower Yangtze Valley metallogenic belt.

关键词： lower crust deep seismic reflection underplating tectonic evolution.

DOUBLE　SUBSTITUTE　CALIBRATION　FOR　THE　ISOTOPIC　RATIO　MEASUREMENT　AMONG　RARE　EARTH　ELEMENTS

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chinese Chemical Letters 1996年第5期7卷 499-502页

作者： Teing Lien CHANG (Department of Chemistry, Peking University, beijing 100871)Dun Min ZHAO (institute of {2., academy of geological sciences. beijing 1.0037) Department of Chemistry Peking University Beijing 100871 institute of geology Academy of Geological Sciences Beijing 100037

Abstract: Through the application of the method of double substitute calibration using the true isotopic ratios of cerium and europium of our laboratory standards, the atomic weight of ytterbium has been determined a... 详细信息

关键词： RATIO CALIBRATION DOUBLE EARTH ELEMENTS FOR ISOTOPIC MEASUREMENT RARE AMONG

Outcrop Sequence Stratigraphy of Neoproterozoic in Hunjiang Area, Jilin Province

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Journal of Earth Science 1996年第1期15卷 20-28页

作者： Qiao Xiufu Gao Linzhi (institute of geology,{2., beijing 1.0037)

Three depositional sequences have been recognized in the Neoproterozoic of southern Jilin. In this paper, we focus discussion on the parasequences and their stacking patterns in Wanlong, Badaojiang and Qinggouzi formations and on their diachronism by the theory of sequence stratigraphy, event stratigraphy and chronostratigraphy. The authors advance a new comparison of the Neoproterozoic between Jilin and Liaoning provinces.

关键词： Neoproterozoic sequence stratigraphy parasequence onlap Jilin Province.