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Distributions of fatty acids in a stalagmite related to paleoclimate change at Qingjiang in Hubei,southern china

Science china earth {2. 2005年第9期48卷 1463-1469页

作者： XIE Shucheng1,HUANG Junhua1,WANG Hongmei2.YI Yi1,HU Chaoyong1, CAI Yanjun3 & CHENG Hai4 1. Faculty of earth Science,china {2. of geosciences,Wuhan 430074,china 2. school of Environmental Studies,china {2. of geosciences,Wuhan 430074,china 3. SKLLQG,Institute of earth Environment,Chinese Academy of sciences,Xi’an 710075,china 4. Department of Geology and Geophysics,{2. of Minnesota,MN55455,USA 1. Faculty of earth Science China University of Geosciences 430074 Wuhan China 2. school of Environmental Studies China University of Geosciences 430074 Wuhan China 3. SKLLQG Institute of Earth Environment Chinese Academy of Sciences 710075 Xi’an China 4. Department of Geology and Geophysics University of Minnesota 55455 MN USA

Fatty acids extracted from a subtropical stalagmite at Qingjiang in Southern china’s Hubei Province were analysed using gas chromatography-mass spectrometry. These n-alkanoic acids range from C14 to C2. in carbon number, maximizing at C16, with a second dominance at C2.. In contrast to the stalagmite analysed, the overlying soils are characterized by the dominance of heavy-molecular-weight homologues (>C2.). The n-fatty acids in the stalagmite were proposed to be contributed by both the soil ecosystems and the microbes harboring in the percolating water and the cave. The ratios of unsaturated to saturated n-fatty acids (C16:1i/C16:0, C18:1/C18:0) appear to show trends comparable with the oxygen isotope records of the stalagmite carbonate, with enhanced values associated with the cold episode such as Heinrich event 1. This paleoclimate-dependent record of the n-fatty acids might reflect microbial changes in physiology and activity in response to the temperature. This record shows somewhat difference from the previous paleoclimate signal extracted from n-alkanols and n-alkan-2.ones of the same stalagmite. The acid record fails to document the well-known Younger Dryas event which was effectively shown by the latter two biomarkers derived from soil ecosystems. This discrepancy might result from the changing biogeochemical impact on different lipid fractions as well as the varied organism populations in different ecosystems.

关键词： biomarker, ecosystem, microbe, speleothem, paleoclimate, Quaternary.

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Multi-isotopic system geochronology of low temperature eclogite from Huangzhen,Southern Dabie Terrain

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Science china earth {2. 2004年第10期47卷 931-942页

作者： CHEN Daogong1, E. Deloule2. CHENG Hao1, XIA Qunke1 & WU Yuanbao1 1. school of earth and Space {2., university of Science and Technology of china, Hefei 2.002., china 2. CRPG-CNRS Nancy, 54501, France 1. school of earth and Space {2. University of Science and Technology of China 230026 Hefei China 2. CRPG-CNRS 54501 Nancy France

Zircon U-Pb thermal ionization mass-spectrometer (TIMS) and secondary ion mass-spectrometer (SIMS) dating, mica and amphibole 40Ar-39Ar dating and mineral Sm-Nd isotopic compositions of Huangzhen low temperature eclogite and country granitic gneiss are carried out. The zircon U-Pb weighted average SIMS age is (2.1.6?9.7) Ma for one eclogite. The mica 40Ar-39Ar isochron age is (2.2.6?2.1) Ma and the lowest plateau age is (2.1.7?2.4) Ma from same sample. U-Pb TIMS concordant ages from other eclogite zircons are from (2.1.3?1.4) Ma to (2.2.5?2.3) Ma. U-Pb SIMS low intercept age from country granitic gneiss is (2.1?35) Ma. The retrograde amphibole 40Ar-39Ar isochron age is (2.5.9?1.0) Ma. Except for mica, which may contain excess 40Ar, all the ages represent peak and retrograde metamorphism of low temperature eclogites. It is indicated that the Huangzhen low temperature eclogites differ from Xiongdian low temperature eclogites of north of the Northern Dabie Terrain in metamorphic ages. Huangzhen low temperature eclogites share one coherent HP-UHP terrain with high temperature eclogites from Southern Dabie Terrain and they may have differences in subduction depth and cooling rates during exhumation.

关键词： low temperature eclogite, multi-isotopic dating, HP-UHP metamorphism, Dabieshan.

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Affinities and functional morphology of the Middle Cambrian ornamented tubules from West Hunan,china

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Progress in Natural Science:Materials International 2004年第10期14卷 67-71页

作者： ZHU Caifa 1,2. and DONG Xiping 1 (1.school of earth and Space {2.,Peking university,Beijing100871,china 2.university of Petroleum,Beijing102.49,china) Peking Univ Sch Earth & Space Sci Beijing 100871 Peoples R China Univ Petr Beijing 102249 Peoples R China

Problematic phosphatic tubular microfossils with ornamented sculptures are documented to exist in limestones of the up-per Middle Cambrian Huaqiao Formation at the Paibi section and the Wangcun section in West Hunan,*** morphological pat-terns,including Ornamented Tube Form I and Ornamented Tube Form II are *** on the analysis of the preservation,wall structure and composition of the fossils,it is deduced that these ornamented tubes may represent carapace spines of some Cambrian arthro-pods with phosphatic carapaces,such as bradoriid *** of functional morphology indicates that the sclerites may rather be considered of a defensive than grasping function on the original organism body.

关键词： Middle Cambrian ornamented tubes affinities functional morphology West Hunan

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Effective solutions to a global 3D visual system in networking environments

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Science china earth {2. 2005年第11期48卷 2032-2039页

作者： ZHANG Liqiang1,2. ZHANG Yan3, YANG Chongjun2. LIU Suhong1, REN Yingchao2. RUI Xiaoping2.& LIU Donglin2.1. State Key Laboratory of Remote Sensing sciences, school of Geography and Remote Sensing, Beijing Normal {2., Beijing 100875, china 2. State Key Laboratory of Remote Sensing sciences, Institute of Remote Sensing Applications, Chinese Academy of sciences, Beijing 101001, china 3. Institute of Geographical sciences and Natural resources Research, Chinese Academy of sciences, Beijing 101001, china 1. State Key Laboratory of Remote Sensing sciences School of Geography and Remote Sensing Beijing Normal University 100875 Beijing China 2. Chinese Academy of sciences State Key Laboratory of Remote Sensing SciencesInstitute of Remote Sensing Applications 101001 Beijing China 3. Institute of Geographical sciences and Natural resources Research Chinese Academy of Sciences 101001 Beijing China

The development of Web-based global 3D visual system has made progresses. However, there exist few mature and effective ways for managing, transmitting and visualizing massive spatial data. Based on the related work, the paper illustrates the ellipsoidal quadtree technique for rapid access multi-scale and multiple level geographical data, integrates the streaming with level-of-detail rendering method for transmitting the data on the network, and im-plements large-scale terrain surface simplification using M-band wavelet transforms and mul-tiresolution triangulations. We fulfil a web-based global terrain visual system using COM com-ponents on the basis of the above techniques. The system has a good prospect in the military simulation and city plans.

关键词： massive spatial data, streaming transmission, system architecture, M-band wavelet

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The developmental trend of labrum and median eyes of Orsten-type preserved Phosphatocopina (Crustacea)

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Science china earth {2. 2010年第1期53卷 18-26页

作者： LIU Zheng 1,2.& DONG XiPing 1,2.1 school of earth and Space {2.,Peking university,Beijing 100871,china 2.State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing Institute of Geology and Palaeontology,Chinese Academy of {2.,Nanjing 2.0008,china 1. school of earth and Space {2. Peking University Beijing 100871 China2. State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China

The Phosphatocopina (Crustacea,Arthropoda) is an important group of 'Orsten-type' preserved *** is resolved as the sister-group of *** we study the labrum,the median eyes,and the inner lamella of Phosphatocopina based on the selected specimens respectively from western Hunan,South china,and *** labrum characters of different species exhibit interspecific *** ratio of labrum length/shield length is significant to the reconstruction of the ontogeny of *** labrum characters should be introduced to the diagnosis of *** the earliest growth stage,the median eyes were inconspicuous,almost as flat as the other area of the ***,with the growth of the individuals they became *** were two obviously concave structures on the ventral side of the hypostome in later stages,which were the positions where the median eyes should have been *** addition,the two modes of preservation of the inner lamella,i.e.,that of shrinking and that of bulging up,are interpreted as the preservational artifact herein.

关键词： Phosphatocopina Crustacea Orsten-type preservation morphology ontogeny Cambrian South china Sweden

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Mechanism for calcite dissolution and its contribution to development of reservoir porosity and permeability in the Kela 2.gas field,Tarim Basin,china

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Science china earth {2. 2008年第4期51卷 567-578页

作者： YU BingSong1,3, DONG HailLiang2.3 & RUAN Zhuang1,3 1 State Key Laboratory of Geological Processes and mineral resources,{2., Beijing 100083, china 2.Department of Geology, Miami university,Oxford, OH 45056, USA 3 Geomicrobiology Laboratory,{2., Beijing, 100083, china State Key Laboratory of Geological Processes and mineral resources China University of Geosciences Beijing 100083 China Department of Geology Miami University Oxford OH 45056 USA Geomicrobiology Laboratory China University of Geoscien

This study is undertaken to understand how calcite precipitation and dissolution contributes to depth-related changes in porosity and permeability of gas-bearing sandstone reservoirs in the Kela 2.gas field of the Tarim Basin, Northwestern china. Sandstone samples and pore water samples are col-lected from well KL2.1 in the Tarim Basin. Vertical profiles of porosity, permeability, pore water chem-istry, and the relative volume abundance of calcite/dolomite are constructed from 3600 to 4000 m below the ground surface within major oil and gas reservoir rocks. Porosity and permeability values are in-versely correlated with the calcite abundance, indicating that calcite dissolution and precipitation may be controlling porosity and permeability of the reservoir rocks. Pore water chemistry exhibits a sys-tematic variation from the Na2.O4 type at the shallow depth (3600-3630 m), to the NaHCO3 type at the intermediate depth (3630―3695 m),and to the CaCl2.type at the greater depth (372.―3938 m). The geochemical factors that control the calcite solubility include pH, temperature, pressure, Ca2. concen-tration, the total inorganic carbon concentration (ΣCO2., and the type of pore water. Thermodynamic phase equilibrium and mass conservation laws are applied to calculate the calcite saturation state as a function of a few key parameters. The model calculation illustrates that the calcite solubility is strongly dependent on the chemical composition of pore water, mainly the concentration difference between the total dissolved inorganic carbon and dissolved calcium concentration (i.e., [ΣCO2. -[Ca2.]). In the Na2.O4 water at the shallow depth, this index is close to 0, pore water is near the calcite solubility. Calcite does not dissolve or precipitate in significant quantities. In the NaHCO3 water at the intermedi-ate depth, this index is greater than 0, and pore water is supersaturated with respect to calcite. Massive calcite precipitation was observed at this depth interval and

关键词： calcite dissolution porosity thermodynamic Tarim Basin

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SHRIMP U-Pb dating and Hf isotopic analyses of Middle Ordovician meta-cumulate gabbro in central Qiangtang, northern Tibetan Plateau

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Science china earth {2. 2010年第5期53卷 657-664页

作者： ZHAI QingGuo1 WANG Jun1, LI Cai2.& SU Li3 1 Institute of Geology, Chinese Academy of Geological sciences, Beijing 100037, china 2.College of {2. sciences, Jilin university, Changchun 130061, china 3 The Geological Laboratory Center and State Key Laboratory of Geological Processes and mineral resources, china university of Geo- sciences, Beijing 100083, china 1. Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China2. College of Earth Sciences Jilin University Changchun 130061 China3. The Geological Laboratory Center and State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China

Metabasites consisting of metamorphic ultra-mafic rocks, cumulate gabbro, gabbro (diabase), basalt, and plagiogranite are exposed at the Taoxinghu area in central Qiangtang, northern Tibetan Plateau. Zircon SHRIMP U-Pb dating for the cumulate gabbro yields a weighted mean age of 467±4 Ma, which is the oldest and most reliable magmatic age in this area. Zircon 176Hf/177Hf ratios range from 0.2.2.15 to 0.2.2.57, with εHf(t) values of 5.02.0.2., indicating that the cumulate gabbro was mainly derived from the depleted mantle. In addition, geochemical data of metabasites suggest that they have similar characteristics to those in the mid-ocean ridge basalts (MORB). The Taoxinghu metabasites may represent the fragment of Early Paleozoic ophiolite in the "Central Uplift" of the Qiangtang, northern Tibetan Plateau.

关键词： Qiangtang cumulate gabbro SHRIMP dating Hf isotope

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Water in peridotite xenoliths from South china

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Science china earth {2. 2011年第10期54卷 1511-1522页

作者： WANG Rong 1,2.3 & ZHANG BaoMin 3 1 Faculty of Land Resource Engineering, Kunming university of Science and Technology, Kunming 650093, china 2.State Key Laboratory for {2. Deposits Research, Nanjing university, Nanjing 2.0093, china 3 Faculty of earth Science, china university of geosciences, Wuhan 430074, china 1. Faculty of Land Resource Engineering Kunming University of Science and Technology Kunming 650093 China2. State Key Laboratory for Mineral Deposits Research Nanjing University Nanjing 210093 China3. Faculty of Earth Science China University of Geosciences Wuhan 430074 China

The water contents of nominally anhydrous clinopyroxene （cpx）, orthopyroxene （opx） and olivine （ol） in peridotite xenoliths hosted by Cenozoic basalts from Yingfengling, Zhangchouchun, Fujitian and Lindi, South china, were measured by Micro- FTIR. All cpx and opx grains contained a certain amount of water, which was indicated by the presence of hydroxyls in the crystal structure. The water contents （H2., ppm） of cpx and opx from peridotite xenoliths of the study areas were 2.3-981, 183-752. 73-586 and 51-42. ppm, and 82.471, 74-571, 53-170 and 9-135 ppm, respectively. No prominent OH absorption bands were detected for any ol grains, indicating that the water contents were below the detection limit （approximately 2.ppm）. The entire rock contents recalculated according to mineral volume proportions were 49-163, 48-168, 2.-111 and 8-40 ppm, respectively. Combined with previously reported data describing the water contents of peridotite xenoliths worldwide, the results presented here suggest that water distribution in the continental lithospheric mantle is spatially heterogeneous at a global scale. The lithospheric mantle of South china is much richer in water than that of the North china Craton, and is close to that typical of off-craton localities, such as the Basin and Range Province, and Massif Central.

关键词： FTIR water peridotite xenoliths South china

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Metallogenic geochemistry of Sb-mineralization in southern margin of North china platform

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Chinese Science Bulletin 1999年第S2期44卷 17-18页

作者： YANG Xiaoyong~1, YANG Xueming~1, ZHANG Jianjun~2. CAO Gaoshe~2.and ZHANG Zhengwei~2.1. Department of earth and Space sciences, {2. of Science and Technlogy of china, Hefei 2.002., china 2. Institute of Geology, Henan Bureau of Geology and mineral resources, Zhengzhou 450053, china Department of earth and Space sciences University of Science and Technology of China Hefei 230026 China Institute of Geology Henan Bureau of Geology and Mineral Resources Zhengzhou 450053 China

1 Geological setting THE Sb mineralization zone in the south margin of North china platform is located in the transitional edgeof North china plate and Yangtze plate, belonging to Qinling fold system, whose tectonic line is inNWW-SEE direction regionally. Because of the huge compression caused by the collision of the twoplates, the rocks undergone strong deformation and metamorphism have very complicated structures. Theregional deep fault-Shuanghuaishu fault-controls Sb-mineralization zone belt, and all the Sb-oredeposits or mineralized spots appear alone at the very southern margin of the fault. The lithostragraphirunits in the mineralized zone are relatively simple, mainly composed of Jiebei Group （Pt2./sub>J2./sup>） of QinglingFormation （with middle-high metamorphsim） and the upper Triassic system （with little metamorphism）.

关键词： Sb-mineralization metallognic geochemistry North china plateform.

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An experimental study of dehydration melting of phengite-bearing eclogite at 1.5―3.0 GPa

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Chinese Science Bulletin 2009年第10期54卷 2090-2100页

作者： LIU Qiang1,2. JIN ZhenMin1,2.& ZHANG JunFeng1,2.1 State Key Laboratory of Geological Processes and mineral resources,{2., Wuhan 430074, china 2.Faculty of earth sciences,{2., Wuhan 430074, china State Key Laboratory of Geological Processes and mineral resources China University of Geosciences Wuhan 430074 China Faculty of earth sciences China University of Geosciences Wuhan 430074 China

Dehydration melting experiments were performed on ultrahigh-pressure eclogite from Bixiling in the Dabie orogen at 1.5―3.0 GPa and 800―950℃ using piston cylinder apparatus. The results show that (1) eclogite with ~5% phengite started to melt at T≤800―850℃ and P = 1.5―2.0 GPa and produced about 3% granitic melt; (2. the products of dehydration melting of phengite-bearing eclogite vary with temperature and pressure. Fluid released from dehydration of phengite and zoisite leads to partial melting of eclogite and formation of plagioclase reaction rim around kyanite at pressures of 1.5―2.0 GPa and temperatures of 800―850℃; (3) phengite reacted with omphacite and quartz and produced oligoclase, kyanite and melt at elevated temperatures. Oligoclase is the primary reaction product produced by partial melting of phengite in the eclogite; and (4) the dehydration melting of phengite-bearing eclogite at pressures of 1.5―3.0 GPa and temperatures ≥900 ℃ results in formation of garnets with higher molar fraction of pyrope (37.67 wt.%―45.94 wt.%). Potassium feldspar and jadeite occur at P = 2.4―3.0 GPa and T≥900 ℃ , indicating higher pressure and fluid-absent conditions. Our results constrain the solidus for dehydration melting of phengite-bearing eclogite at pressures of 1.5―3.0 GPa. Combining experi- mental results with field observations of partial melting in natural eclogites, we concluded that phengite-bearing eclogites from the Dabie-Sulu orogen were able to partially molten at P = 1.5―2.0 GPa and T = 800―850℃ during exhumation. The ultrahigh-high pressure eclogites would have experienced partial melting in association with metamorphic phase transformation under different fluid conditions.

关键词：超高压榴辉岩脱水熔融实验水白云母反应压力部分熔融大别造山带苏鲁造山带反应产物

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