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Transition from platemargin to intraplate environment: Geochemistry of basalts in Paleogene Liaohe basin, northeastern china

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Science china earth Sciences 2005年第12期48卷 2069-2080页

作者： WU Changzhi1, GU Lianxing1, REN Zuowei1,2. ZHANG Zunzhong1, CHEN Zhenyan2.& ZHAO Ming1 1. State Key Laboratory of Mineral Deposit Research (Nanjing University), Department of earth Sciences, Nanjing University, Nanjing 2.0093, china 2. Exploration and Development Research {2. of Liaohe Oilfield Branch Company, Petrochina, Panjin 12.010, china State Key Laboratory of Mineral Deposit Research (Nanjing University) Department of Earth Sciences Nanjing University Nanjing China Exploration and Development Research institute of Liaohe Oilfield Branch Company PetroChina Panjin China

Paleogene basalts from the Liaohe basin, northeastern china, are dominated by alkaline olivine basalts and olivine basalts. These basalts are generally enriched in high field strength elements (HFSE), depleted in large ion lithophile elements (LILE) and comparable to those of typical ocean island basalts (OIB). Positive anomalies of Ba, Sr and Zr with high Nb/U, U/Pb, Ce/Pb and Zr/Hf ratios imply that materials from an oceanic crust had been added to the mantle sources of the basalts. In addition, the basalts are generally depleted in Sr, Nd and Pb isotopes, indicating that an enriched mantle (EMI) and a depleted mantle (DM) sources were added to the OIB-like resource. Comprehensive research on lithosphere evolution and tectonic setting of the Liaohe basin and surrounding areas suggests that these basalts were derived by variable degrees of partial melt-ing from an upwelling asthenosphere mantle. Materials from an oceanic lithosphere were added to the source in company with Paleogene tectonic transition from platemargin to intraplate envi-ronment. Retreating and steepening of the subducting Pacific oceanic plate could be the main cause for the tectonic environment transition.

关键词： geochemistry, basalt, Paleogene, Liaohe basin, North china Block, eastern china.

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Geomorphologic evidence of phased uplift of the northeastern Qinghai-Tibet Plateau since 14 million years ago

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Science china earth Sciences 2004年第9期47卷 822-833页

作者： LU Huayu1, WANG xiaoyong1, AN Zhisheng1, MIAO xiaodong1, ZHU Rixiang3, MA Haizhou2. LI Zhen4, TAN Hongbing2.& WANG xianyan1 1. State Key Laboratory of Loess and Quaternary Geology, institute of earth {2., Chinese Academy of Sciences, xi’an 710075 china 2. Qinghai institute of Salt Lakes, Chinese Academy of Sciences. xining 810008, china 3. institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 10002., china 4. Department of Geography, Qinghai Normal University, xining 810008, china State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Qinghai institute of Salt Lakes Chinese Academy of Sciences Xining China Department of Geography Qinghai Normal University Xining China

A typical sequence of fluvial terraces and aeolian deposits overlying these ter- races were multidisciplinary investigated. New evidences for uplift process of the northeastern Qinghai-Tibetan Plateau in the past 14 million years were obtained. At least 11 river terraces along Huangshui, the first-class tributary of Yellow River, at the xining-Huzhu region are identi- fied. While the first one (T1) is classified as an accumulation terrace, the others are all basement river terraces, which consist of the Tertiary sandstone and siltstone bedrock, fluvial gravel and pebbles and the overlying aeolian loess-Red Clay deposit. Samples from the aeolian deposits were examined for paleomagnetic stratigraphic reconstruction (1030 samples), luminescence dating (16 samples), magnetic susceptibility and grain-size distribution (more than 4000 sam- ples). The luminescence dating and stratigraphic correlation suggest that terraces of Tll, T10, T8, T7, T3, T2. T1 were formed at 14, 11.3, 1.55, 1.2. 0.15, 0.07 and 0.01 million years ago, re- spectively. Sedimentological analysis and geomorphological observation indicate that formation and evolution of these terraces were mainly driven by tectonic uplift. Therefore, the terrace se- quence provides an ideal geological record, of the uplift process of the northeastern during the past 14 million years, and the timings of the terraces formation are regarded as the timings of tectonic uplift. The significant uplifting events took place at 14, 11.3, 1.2.and 0.15 mil- lion years ago, respectively. The fluvial incision at the xining-Huzhu region is less than 100 m during a period of ~12.million years in the Miocene era (between the Tll and T9), while the Huangshui River had incised 432.m during the past 1.2.million years (from T7 to the present floodplain). The river incision process clearly demonstrates that accelerated rising of the north- eastern Qinghai-Tibet Plateau during the late Cenozoic, and provides new evidence of previous thoughts

关键词： river terrace, tectonic uplift, loess-Red Clay, the past 14 million years, northeastern Qinghai-Tibet Plateau.

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A study on environmental aridity over northern and southern to Qinling Mountains under climate warming

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Journal of Geographical Sciences 2001年第2期11卷 193-201页

作者： YAN Jun-ping~1, LIU Yan-sui~2.(1. College of Tourism and environment, Shaanxi Normal University, xi’an 710062. china 2. {2. of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, china) College of Tourism and environment Shaanxi Normal University institute of Geographic Sciences and Natural Resources Research CAS

Based on the data up to 1999 from hydroclimatological departments, this pape analyzes the climatic divide implications of the Qinling Mountains in regional response to the process of climate warming, due to which the grades of dryness/wetness (GDW) in 100 years show that the northern region has entered a drought period, while the southern is a humid period. In a course of ten years, the D-value of annual average air temperature over southern Shaanxi (the Hanjiang Valley) and the Central Shaanxi Plain (the Guanzhong Plain) has narrowed, i.e., the former with a slight change and the latter with rapid increase in temperature. Both regions were arid with the decrease in precipition D-value, namely the plain became warmer while the south was drier. The Qinling Mountains play a pronounced role in the climatic divide. The runoff coefficient (RC) of the Weihe River decreases synchronously with that of the Hanjiang due to climate warming. The RC of Weihe dropped from 0.2.in the 1950s to less than 0.1 in the 1990s. The Weihe Valley (the Guanzhong Plain) is practically an arid area due to shortage of water. The successive 0.5, 1.0°C temperature anomaly over china marks, perhaps, the improtant transition period in which the environment becomes more vulnerable than before. The study shows the obvious trend of environmental aridity, which is of help to the understanding of regional response to global climate change.

关键词： climate change aridity Qinling Mountains

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Optimum segmentation of simple objects in high-resolution remote sensing imagery in coastal areas

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Science china earth Sciences 2006年第11期49卷 1195-1203页

作者： CHEN Jianyu1,2. PAN Delu1 & MAO Zhihua1 1. State Key Laboratory of Satellite Ocean environment Dynamics, Second institute of Oceanography, State Oceanic Admini- stration, Hangzhou 310012.{2. 2. Shanghai institute of Technical Physics, Chinese Academy of Science, Shanghai 2.0083,{2. State Key Laboratory of Satellite Ocean environment Dynamics Second Institute of Oceanography State Oceanic Administration Hangzhou China Shanghai institute of Technical Physics Chinese Academy of Science Shanghai China

The optimum segmentation of ground objects in a landscape is essential for interpretation of high-resolution remotely sensed imagery and detection of objects; and it is also a technical foundation to efficiently use spatial information in remote sensing imagery. Landscapes are complex system composed of a large number of heterogeneous components. There are many explicit homogeneous image objects that have similar spectral character and yet differ from surrounding objects in high-resolution remote sensing imagery. Thereby, a new concept of Distinctive Feature of fractal is put forward and used in deriving Distinctive Feature curve of fractal evolution in multiscale segmentation. Through distinguishing the extremum condition of Distinctive Feature curve and the inclusion relationship of fractals in multiscale representation the Scalar Order is built. This can help to determinate the optimum scale in image segmentation for simple-objects, and the potential meaningful image-object fitting the intrinsic scale of the dominant landscape object can be obtained. Based on the application in high-resolution remote sensing imagery in coastal areas, a satisfactory result was acquired.

关键词： optimum scale, multiscale segmentation, image interpretation, remote sensing, coastal area.

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Bubble size distribution in surface wave breaking entraining process

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Science china earth Sciences 2007年第11期50卷 1754-1760页

作者： HAN Lei1,2.& YUAN YeLi2.1 Department of Ocean environment, Ocean University of china, Qingdao 2.6003, china 2.The First institute of Oceanography, State Ocean Administration, Qingdao 2.6061, china Department of Ocean environment Ocean University of China Qingdao China The First institute of Oceanography State Ocean Administration Qingdao China

From the similarity theorem, an expression of bubble population is derived as a function of the air en-trainment rate, the turbulent kinetic energy (TKE) spectrum density and the surface tension. The bubble size spectrum that we obtain has a dependence of a?2.5+nd on the bubble radius, in which nd is positive and dependent on the form of TKE spectrum within the viscous dissipation range. To relate the bubble population with wave parameters, an expression about the air entrainment rate is deduced by intro-ducing two statistical relations to wave breaking. The bubble population vertical distribution is also derived, based on two assumptions from two typical observation results.

关键词： wave breaking,bubble cloud,bubble size spectrum

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Petrogenesis and significance of early Yanshanian syenite-granite complex in eastern Nanling Range

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Science china earth Sciences 2005年第7期48卷 912-924页

作者： CHEN Peirong1, ZHOU xinmin1, ZHANG Wenlan1, LI Huimin2. FAN Chunfang1, SUN Tao1, CHEN Weifeng1 & ZHANG Min1 1. State Key Laboratory of Mineral Deposits Research, Department of earth Sciences, Nanjing University, Nanjing 2.0093, china 2. Tianjin {2. of Geology and Mineral Resources, china Geological Survey, Tianjin 300170, china State Key Laboratory of Mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing 210093 China Tianjin institute of Geology and Mineral Resources China Geological Survey Tianjin 300170 China

In the eastern Nanling Range there exists the early Yanshanian syenite-granite assemblage. A representative example is the Pitou-Tabei complex composed of the Tabei syenite pluton and the Pitou syenogranite pluton in southern Jiangxi Province. U-Pb zircon dating yields ages of 188.6±2.2.Ma for the Tabei pluton and 186.3±1.1 Ma for the Pitou pluton. The Tabei syenite is characterized by relatively low SiO2.content (62.40% - 68.75%), high alkalis (K2.+Na2. = 10.56%-11.96%), low percent K2./Na2. ratios (0.56-0.93), metaluminous fea- ture (A/CNK = 0.80-1.00), enrichment in LILE (Rb, Ba, K) and HFSE (Th, U, Nb, Ta, Zr, and so on), weakly negative to positive Eu anomalies (δ Eu = 0.63-1.82., relatively low (87Sr/86Sr)i (0.70412.0.70543), and relatively high ε Nd(t) (3.14-3.52.. The Pitou syenogranite is charac- terized by high silicon content (SiO2.= 71.06%-76.2.%), relatively low alkalis (K2.+Na2. = 8.10%-9.80%), high percent K2./Na2. ratios (1.2.-1.94), metaluminous feature (A/CNK = 0.94-1.07), enrichment in Rb, Th (U), K, depletion in Ba, Nb, Ta, Sr, P , Zr, Ti, high ΣREE (av- eraging 451.03 μg/g), strong negative Eu anomalies (δ Eu = 0.2.-0.33), relatively high (87Sr/86Sr)i (0.70805-0.70912., and relatively low ε Nd( t ) (?5.35-?6.2.). The Tabei syenite and Pitou syenogranite both have the characteristics of A-type granites. The former is considered to be from the asthenosphere mantle, and the latter was the product of the crust-mantle mixture. They both were probably formed in a rifting setting.

关键词： syenite-granite assemblage single zircon U-Pb age rifting environment Nanling Range.

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Nitrogen isotopic composition of plant-soil in the Loess Plateau and its responding to environmental change

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Chinese Science Bulletin 2009年第2期54卷 272-279页

作者： LIU WeiGuo1,2.& WANG Zheng1,3 1 State Key Laboratory of Loess and Quaternary Geology, institute of earth {2., Chinese Academy of Sciences, xi’an 710075, china 2.xi’an Jiaotong University, School of Human Settlement and Civil Engineering, xi’an 710049, china 3 Graduate University of Chinese Academy of Sciences, Beijing 100049, china State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China School of Human Settlement and Civil Engineering Xi’an Jiaotong University Xi’an China Graduate University of Chinese Academy of Sciences Beijing China

The nitrogen isotope of soil is of emerging significance as an indicator of climatic change and biogeochemical cycle of nitrogen in nature systems. In this paper, the nitrogen content and isotopic composition of modern ecosystems from arid and semiarid Loess Plateau in northwestern china, including plant roots and surface soil, were determined to investigate trends in δ15N variation of plant roots and soil along a precipitation and temperature gradient in northwestern china under the East Asian Monsoon climate condition. The δ15N values of surface soil from the study area vary from ?1.2. to 5.8‰, but from -5.1‰ to 1.9‰ in the plant roots. Our results indicate that (1) although the isotopic compositions of both plant roots and surface soil change with a similar trend along the climate gradient, the apparent nitrogen difference between plant roots and soil existed, with -δ15N values ranging from 0.3‰ to 7.2. with average of 4.1‰; and (2. mean annual precipitation (MAP) is the dominant factor for isotopic composition of plant-soil nitrogen in the Loess Plateau, and the δ15N values are less correlated with MAT; we suggest that nitrogen isotopic composition of soil is a potential tracer for {2.al changes.

关键词：氮同位素物理性质化学性质环境论

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Genesis of ultra-deep dolostone and controlling factors of largescale reservoir:A case study of the Sinian Dengying Formation and the Cambrian Longwangmiao Formation in the Sichuan Basin

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Science china earth Sciences 2024年第7期67卷 2352-2382页

作者： xi LI Guangyou ZHU Zhiyao ZHANG Petrochina Research institute of Petroleum Exploration and Development Beijing 100083China School of Geosciences Yangtze UniversityWuhan 430100China School of earth Resoures China University of GeosciencesWuhan 430074China

This paper investigates the origin of ultra-deep dolostone and the factors influencing large-scale dolostone reservoirs,focusing on the Sinian Dengying Formation and the Cambrian Longwangmiao Formation in the Sichuan *** study involves petrology,microscale X-ray diffraction,trace element analysis,and C-O-Sr-Mg isotope experiments to provide a detailed *** research findings indicate that the Dengying and Longwangmiao formations comprise six types of matrix dolostone and four types of *** Dengying Formation,which developed under a sedimentary background of a restricted platform,contains special microbial and microcrystalline *** dolomite grains are small(2.)Mg value is small(Min=-2.31‰).Powder crystal,fine-crystalline,and calcite dolostones with coarser and more ordered crystals exhibit similar δ^(13)C and^(87)Sr/^(86)Sr values to microbial and microcrystalline *** the sedimentary period of the Dengying Formation,ancient marine conditions were favorable for microbial *** induced the direct precipitation of primary dolomite in seawater,forming microbial and microcrystalline dolostones during the seawater diagenesis *** the subsequent diagenesis period,dolostones underwent the effects of dissolution-recrystallization,structures,and hydrothermal *** resulted in the formation of dolostone with coarser crystals,a higher degree of order,and various types of *** Longwangmiao Formation was developed in an interplatform beach characterized by special particle *** particle dolostone has a large grain size(>30μm),high order degree(Min=0.7),small unit cell parameters,high Na content

关键词： Ultra-deep layers Dolostone Supercontinent evolution Microscale geochemistry Dengying Formation Longwangmiao Formation Sichuan Basin

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Glacial atmospheric CO_(2. decline in association with decrease of marine sedimentary phosphorus

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Science china earth Sciences 2006年第3期49卷 322-330页

作者： WENG Huanxin1, ZHANG xingmao1, WU Nengyou2. WANG Ying1, CHEN Lihong1, ZHONG Hexian2.& QIN Yachao1 1. institute of environment & Biogeochemistry, Zhejiang University, Hangzhou 31002.,{2. 2. Guangzhou Marine Geological Survey, CGS, MLR, Guangzhou 510760,{2. institute of environment & Biogeochemistry Zhejiang University Hangzhou China Guangzhou Marine Geological Survey CGS MLR Guangzhou China

The environmental and biogeochemical information extracted from the sediments col- lected from the northern shelf of the South china Sea shows that terrigenous inputs of phosphorus into the sea remained relatively constant, and the variation of phosphorus contents at different depths was caused by climatic and environmental changes. The findings also suggest that the vertical varia- tion of phosphorus content was opposite to those of calcium carbonate and cadmium, and the func- tional correlation between CO2.and PO43? in seawater was given by calculating the chemical equilib- rium, indicating that the accumulation of marine sedimentary phosphorus may have something to do with the variation of atmospheric CO2. The decreased phosphorus accumulation as well as the cor- respondingly-increased calcium carbonate content might be one of key factors causing glacial at- mospheric CO2.decline.

关键词： sedimentary phosphorus, calcium carbonate, atmospheric CO2. northern shelf of the South china Sea, biogeochemistry.

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Lattice-based artificial endocrine system model and its application in robotic swarms

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Science china(Information Sciences) 2011年第4期54卷 795-811页

作者： XU QingZheng 1,2.& WANG Lei 1 1 School of Computer Science and Engineering,xi’an University of Technology,xi’an 710048,china 2.xi’an Communication institute,xi’an 710106,china School of Computer Science and Engineering Xi’an University of Technology Xi’an China xi’an Communication institute Xi’an China

To solve the problem of controlling robot swarms in a distributed manner,we propose a novel latticebased artificial endocrine system (LAES) model,inspired by modern endocrinology *** on a latticed environment,relying on cell intelligentization,connected by cumulative hormones,and directed by target cells,the LAES model can finally adapt to the continuous volatility of the external environment and maintain the relevant stability of the internal dynamics of the system,thus exhibiting the self-organizing and self-repairing features of the biological endocrine *** show that the LAES model enables a robotic swarm to search an unfamiliar space and seize multiple targets automatically without using unique global identifiers or a centralized control strategy for the individual *** demonstrates that the model can reliably be used to simulate large scale swarm behavior through wireless communication.

关键词： artificial endocrine system robotic swarms endocrine cell hormone self organization self repair searching and seizing

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