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鄂尔多斯盆地东缘上古生界致密储层含气系统压力演化 被引量:2
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作者 李勇 朱治同 +2 位作者 吴鹏 申陈州 高计县 《石油与天然气地质》 EI CAS CSCD 北大核心 2023年第6期1568-1581,共14页
鄂尔多斯盆地东缘上古生界多层系致密气发育,准确认识气藏压力演化过程对深化致密气成藏认识和实现气井高产稳产具有指导意义。综合应用钻测井资料和岩心流体包裹体测试,结合盆地埋藏史和热演化史模拟,揭示了鄂尔多斯盆地东缘上古生界... 鄂尔多斯盆地东缘上古生界多层系致密气发育,准确认识气藏压力演化过程对深化致密气成藏认识和实现气井高产稳产具有指导意义。综合应用钻测井资料和岩心流体包裹体测试,结合盆地埋藏史和热演化史模拟,揭示了鄂尔多斯盆地东缘上古生界含气系统压力演化。结果显示,研究区自下而上发育欠压、略微欠压和常压系统。均一温度和盐度总体上连续分布,反映了油气连续充注过程。太原组、山西组和下石盒子组均一温度和盐度正相关,反映近源生烃后快速充注;上石盒子组和石千峰组均一温度和盐度负相关,受流体远距离运移充注和紫金山构造热事件作用下的气藏再平衡影响。研究区在白垩纪中期大量生烃,形成了异常高压,储层压力在34.89~38.26 MPa。后期地层抬升造成储层压力降低,其中地层降温贡献了50.31%~57.85%;天然气膨胀引起的气体运移贡献了28.25%~41.95%,且以上部地层降低为主;孔隙反弹贡献了0.37%~0.79%。相关成果系统揭示了上古生界致密气藏压力系统演化及现今气藏压力成因,对于认识鄂尔多斯盆地和类似盆地致密气富集成藏规律具有借鉴意义。 展开更多
关键词 流体包裹体 压力系统 致密气 上古生界 临兴地区 鄂尔多斯盆地
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Population Density and Habitat Utilization of Ibex(Capra ibex)in Tomur National Nature Reserve,Xinjiang,China 被引量:9
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作者 徐峰 马鸣 吴逸群 《Zoological Research》 CAS CSCD 北大核心 2007年第1期53-55,共3页
Surveys was conducted to study the population density and habitat utilization of the ibex (Capra ibex) in Tomur National Nature Reserve during October- December 2005. The results are as follows: ① The mean group s... Surveys was conducted to study the population density and habitat utilization of the ibex (Capra ibex) in Tomur National Nature Reserve during October- December 2005. The results are as follows: ① The mean group size of the ibex in Tomur Nature Reserve is 8.43 and the population density is 269.76/100 km^2; ② The ibex prefer areas with steep slope (between 30° -45°), broken substrates and cliffs nearby ( 〈 100 m). They avoid grasslands and fiat hillsides; ③The probable reason for this habitat selection is serf-protection. 展开更多
关键词 IBEX POPULATION Habitat utilization Tomur National Nature Reserve
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Determination of Naftopidil in Dog Plasma by High Performance Liquid Chromatography and Study on Its Pharmacokinetics
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作者 丁劲松 蒋学华 朱浩 《Journal of Chinese Pharmaceutical Sciences》 CAS 2000年第4期200-203,共4页
建立HPLC方法测定犬血浆中的萘哌地尔浓度,研究萘哌地尔胶囊在犬体内的药物动力学。单剂量给予5只健康犬萘哌地尔胶囊200mg,血浆样品碱化后,经乙醚提取以乙腈:磷酸盐缓冲液(0.05mol·L^-1的磷酸二氢钾溶液,以0.1mol·L^-... 建立HPLC方法测定犬血浆中的萘哌地尔浓度,研究萘哌地尔胶囊在犬体内的药物动力学。单剂量给予5只健康犬萘哌地尔胶囊200mg,血浆样品碱化后,经乙醚提取以乙腈:磷酸盐缓冲液(0.05mol·L^-1的磷酸二氢钾溶液,以0.1mol·L^-1的NaOH调节pH至6.5)=60:40(v/v)为流动相,由ODS C18分析柱分离测定,紫外230nm为检测波长,维拉帕米为内标。线性范围为10ng·L^-1;方法回收率为:100.23±3.00%;检测限:8ng·mL^-1;日间RSD≤5.56%,日内RSD≤3.30%。本法简便,回收率和灵敏度高,可用于萘哌地尔制剂的药动学研究。单剂量给予犬萘哌地尔胶囊200mg后血药浓度随时间变化规律符合一级吸收一室模型,T1/2Ke为3.19±1.27h,Tmax为1.15±0.59h,Cmax为697.48±94.22ng·mL^-1. 展开更多
关键词 NAFTOPIDIL HPLC PHARMACOKINETICS
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Preview of the No.1148 Ramsar Site on the Ordos upland of western Inner Mongolia
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作者 何芬奇 任永奇 白秀芳 《Chinese Birds》 2010年第1期80-81,共2页
The Taolimiao-Alashan Nur (T-A Nur), of about 10 km2 a brackish lake located on the Ordos upland of western Inner Mongolia, northern China, used to
关键词 No.1148 Ramsar Site the Ordos upland western Inner Mongolia
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Dynamic Change and Simulation and Prediction of the Karst Rocky Desertification Sensitivity in Guizhou Province
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作者 安宏锋 安裕伦 +1 位作者 袁士聪 张跃红 《Agricultural Science & Technology》 CAS 2010年第11期155-161,共7页
Sensitivity evaluation of rocky desertification is to recognize the areas prone to be rock-deserted,so as to assess the sensitivity degree of rocky desertification to human activities.To perform the sensitivity evalua... Sensitivity evaluation of rocky desertification is to recognize the areas prone to be rock-deserted,so as to assess the sensitivity degree of rocky desertification to human activities.To perform the sensitivity evaluation of rocky desertification,we should be on the basis of the mechanism of rocky desertification formation for analyzing its regional distribution difference in the sensitivity and further for finding out the rocky desertification-susceptive areas and their possible degrees.Employing remote sensing and geological information system techniques,we regarded the 1∶ 50 000 topographic map and the TM image in 2000 of Guizhou Province,together with the hydrologic map,soil map,geologic map,rock formation map,administrative map and other geological information as data sources to generate the degree data of rocky desertification sensitivity of Guizhou Province in 1962 and 2000,based on which we determined the corresponding degree transfer matrix and adopted Markov model to simulate the dynamic change process of rocky desertification sensitivity and its future evolution trend.In various sensitivity types of rocky desertification in Guizhou Province,only the insensitive type showed a declined acreage,from the proportion of total land acreage of 61.35% in 1962 to 55.55% in 2000.Various sensitivity types inter-conversed,resultantly the acreage of mildly sensitive type increased most.The prediction results showed that the acreage of insensitive type of rocky desertification in Guizhou Province will assume a remarkable decline trend,of mildly sensitive type will present a remarkably increasing trend and of slightly sensitive type basically will maintain a stable level in the future tens of years.Acreages of both highly sensitive and extremely sensitive type of rocky desertification expanded to some extent,suggesting that the rocky desertification risk in Guizhou Province is in an aggravating process. 展开更多
关键词 KARST Sensitivity of rocky desertification Rock assemblages SLOPE Land use Markov model Guizhou Province
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Seismic dip estimation based on the twodimensional Hilbert transform and its application in random noise attenuation 被引量:6
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作者 刘财 陈常乐 +3 位作者 王典 刘洋 王世煜 张亮 《Applied Geophysics》 SCIE CSCD 2015年第1期55-63,121,共10页
In seismic data processing, random noise seriously affects the seismic data quality and subsequently the interpretation. This study aims to increase the signal-to-noise ratio by suppressing random noise and improve th... In seismic data processing, random noise seriously affects the seismic data quality and subsequently the interpretation. This study aims to increase the signal-to-noise ratio by suppressing random noise and improve the accuracy of seismic data interpretation without losing useful information. Hence, we propose a structure-oriented polynomial fitting filter. At the core of structure-oriented filtering is the characterization of the structural trend and the realization of nonstationary filtering. First, we analyze the relation of the frequency response between two-dimensional(2D) derivatives and the 2D Hilbert transform. Then, we derive the noniterative seismic local dip operator using the 2D Hilbert transform to obtain the structural trend. Second, we select polynomial fitting as the nonstationary filtering method and expand the application range of the nonstationary polynomial fitting. Finally, we apply variableamplitude polynomial fitting along the direction of the dip to improve the adaptive structureoriented filtering. Model and field seismic data show that the proposed method suppresses the seismic noise while protecting structural information. 展开更多
关键词 Two-dimensional Hilbert transform random noise attenuation structure protection nonstationary polynomial fitting local seismic d
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Application of unscented Kalman filter to novel terrain passive integrated navigation system 被引量:2
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作者 王其 徐晓苏 《Journal of Southeast University(English Edition)》 EI CAS 2007年第4期545-549,共5页
To improve the navigation accuracy of an autonomous underwater vehicle (AUV), a novel terrain passive integrated navigation system (TPINS) is presented. According to the characteristics of the underwater environme... To improve the navigation accuracy of an autonomous underwater vehicle (AUV), a novel terrain passive integrated navigation system (TPINS) is presented. According to the characteristics of the underwater environment and AUV navigation requirements of low cost and high accuracy, a novel TPINS is designed with a configuration of the strapdown inertial navigation system (SINS), the terrain reference navigation system (TRNS), the Doppler velocity sonar (DVS), the magnetic compass and the navigation computer utilizing the unscented Kalman filter (UKF) to fuse the navigation information from various navigation sensors. Linear filter equations for the extended Kalman filter (EKF), nonlinear filter equations for the UKF and measurement equations of navigation sensors are addressed. It is indicated from the comparable simulation experiments of the EKF and the UKF that AUV navigation precision is improved substantially with the proposed sensors and the UKF when compared to the EKF. The TPINS designed with the proposed sensors and the UKF is effective in reducing AUV navigation position errors and improving the stability and precision of the AUV underwater integrated navigation. 展开更多
关键词 autonomous underwater vehicle strapdown inertial navigation system unscented Kalman filter extended Kalman filter terrain passive integrated navigation system
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The Effects of Ethanolamine Nitrate Ester Ferulate (ENF)on Isolated Working Guinea Pig Heart and Rat AorticRing
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作者 史道华 张翼 郭兆贵 《Journal of Chinese Pharmaceutical Sciences》 CAS 1996年第1期1-6,共6页
The cardiac and vascular effect of ethanolamine nitrate ester ferulate (ENF) wasinvestigated on isolated working guinea pig heart (IWH) and rat aortic ring. The coronary blood flowwas remarkably increased while the c... The cardiac and vascular effect of ethanolamine nitrate ester ferulate (ENF) wasinvestigated on isolated working guinea pig heart (IWH) and rat aortic ring. The coronary blood flowwas remarkably increased while the cardiac functions of IWH were not significantly altered by ENFranging from 10-8 to 10-4 mol/L. The percentages of vasorelaxation of ENF t 10 μmol/L) and nicoran-dil (NIC, 10 μmol/L) on K+ (80 mmol/L)-induced contraction in aortic rings were 72 ± 8% and17±8%, respectively. The relaxation effects of ENF and NIC on phenylephrine (PE, 5 μmol/L) in-duced contraction were in a dose-dependent manner. When vessel segments were exposed to PE withmethylene blue (MB, 10 μmol/L) or with glibenclamide (GLI, 10 pmol/L), the percentages of relaxa-tion of ENF (10 μmol/L) and NIC ( 1 0 μmol/L) were 4 1 ±11 % and 49±7% or 76± 14% and the 33±9%,respectively. The results suggested that ENF improved coronary circulation and the vasodilation of ENF was mediated bv nitrate-like action. 展开更多
关键词 Ethanolamine nitrate ester ferulate. Nicorandil. Cardiac function Vasodila-tion lsolated working heart
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Analysis of tunnel face stability with advanced pipes support 被引量:12
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作者 AN Yong-lin ZHOU Jin +1 位作者 OUYANG Peng-bo LI Jia-hao 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第2期604-617,共14页
To keep the tunnel face stable is very important for tunnel construction.In this paper,the tunnel face stability under the advanced pipe was analyzed using the Winkler foundation model and rigid limit equilibrium.The ... To keep the tunnel face stable is very important for tunnel construction.In this paper,the tunnel face stability under the advanced pipe was analyzed using the Winkler foundation model and rigid limit equilibrium.The tunnel face deformation characteristics were also analyzed using the numerical simulation.The influence of parameters on the deflection of the pipe roof and the stability of the tunnel face were discussed.The results show that the tunnel face stability can be improved through increasing the pipe diameter,decreasing the initial displacement at the beginning of the pipe seat,and adopting the short round length and small excavation height.With the increase of tunnel burial depth,the safety factor of tunnel face stability first decreases,then increases,and then remains unchanged.The deformation at the center of the tunnel face is larger than the deformation at the surround sides and at the corner.The horizontal displacement varies little with the increasing of the pipe length.The horizontal displacement at the center of the tunnel face increases with the increase of the pipe ring spacing and the pipe longitudinal spacing.There is an optimum external angle. 展开更多
关键词 tunnel face stability advanced pipe Winkler foundation model numerical simulation
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Morphotectonic and Lithostratigraphic Analysis of Intermontane Karewa Basin of Kashmir Himalayas,India 被引量:4
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作者 Reyaz Ahmad DAR Rakesh CHANDRA Shakil Ahmad ROMSHOO 《Journal of Mountain Science》 SCIE CSCD 2013年第1期1-15,共15页
Morpho-tectonic study plays an important role in deciphering the effects of tectonic activity in the geomorphic evolution of the drainage basins.Romushi watershed forms one of the major watersheds of the intermontane ... Morpho-tectonic study plays an important role in deciphering the effects of tectonic activity in the geomorphic evolution of the drainage basins.Romushi watershed forms one of the major watersheds of the intermontane Karewa Basin of Kashmir Valley.The Karewa sediments are characterized by glacio-fluvio-lacustrine deposits capped by the aeolian loess.The geomorphic,morphometric and lithostratigraphic studies of these cap deposits have been carried out to elucidate the effect of tectonics on the geomorphic evolution of Romushi Watershed.Geomorphic mapping was carried out using GPS measurements,DEM at 30m resolution,Topographic Position Index(TPI) model,topographic maps,LANDSAT TM Imagery and field data.Morphometric and morphotectonic analyses in GIS environment were used to calculate various geomorphic indices(Mountain Front Sinuosity Index,Bifurcation Ratio,Asymmetry Factor,River Profile,etc).These indices reveal that the tectonic uplift observed in the region due to Himalayan orogeny coupled with mass movement and aeolian deposition have dominated the landscape evolution of intermontane Karewa Basin of Kashmir throughout the Late Quaternary Period.Additional data from lithostratigraphic measurements were analyzed to understand the geomorphic evolution of intermontane Karewa Basin.The data revealed that the basin has experienced differential uplift and erosion rates from time to time in the geological past.This was corroborated by the results from the morphometric and morphotectonic analysis. 展开更多
关键词 Himalayas Morphometry Watershed Morphotectonics Intermontane basin Remote Sensing Drainage basin Digital elevation model
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Higher Species Diversity Occurs in More Fertile Habitats Without Fertilizer Disturbance in an Alpine Natural Grassland Community 被引量:3
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作者 WANG Dong WU Gao-Lin +3 位作者 CHANG Xiao-Feng SHI Zhi-Hua SUN Lei WEI Xue-Hong 《Journal of Mountain Science》 SCIE CSCD 2014年第3期755-761,共7页
Are there some relationships among species diversity and soil chemical properties of high altitude natural grasslands? Plant community composition and chemical properties of soil samples were compared to investigate t... Are there some relationships among species diversity and soil chemical properties of high altitude natural grasslands? Plant community composition and chemical properties of soil samples were compared to investigate the relationship between soil and species diversity, and the richness in Tibetan alpine grasslands. Results showed that species diversity was significantly positively related to soil organic matter(SOM), total nitrogen(TN),available nitrogen(AN), total phosphorus(TP),available phosphorus(AP), and available potassium(AK) in the high alpine grasslands. Margalef's species richness index was also significantly positively related to SOM, TN, AN, and TP. Most soil chemical properties showed significantly positive correlation with species diversity and Margalef's richness index.Our results suggested that higher plant species richness index and diversity occurred in more fertile soil habitats in high altitude natural grassland community. In practice, fertilization management for the restoration of degraded grassland should be conducted with reference to the nutrient levels ofnatural grassland without the additional artificial fertilizer and with higher species-diversity and richness index. 展开更多
关键词 Species richness Soil properties Species diversity Biomass
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Depositional conditions and modeling of Triassic Oil shale in southern Ordos Basin using geochemical records 被引量:3
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作者 LI De-lu LI Rong-xi +3 位作者 TAN Cheng-qian ZHAO Di) LIU Fu-tian ZHAO Bang-sheng 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第12期3436-3456,共21页
Based on the element geochemistry and biomarkers of the oil shale from the Chang 7 sub-unit in the southern Ordos Basin,the depositional conditions and organic source of the oil shale are discussed.Biomarkers analyses... Based on the element geochemistry and biomarkers of the oil shale from the Chang 7 sub-unit in the southern Ordos Basin,the depositional conditions and organic source of the oil shale are discussed.Biomarkers analyses show that the oil shale has a homologous organic matter source,with a mix of plankton and advanced plants.U/Th and V/Ni ratios suggest that the redox condition is dominated by a reducing condition,and the degree of anoxia in the Tongchuan area is higher than that of the Xunyi area.Sr/Ba ratios illustrate that the oil shale is deposited in fresh water and the paleosalinity in the Tongchuan area is slightly higher.Fe/Ti ratios imply that the Tongchuan area underwent obvious hydrothermal fluid activities.Sr/Cu ratios show warm and humid paleoclimate in both areas.As assessed by(La/Yb)NASC,the deposition rate in the Tongchuan area is relatively lower.Fe/Co and Th/U ratios suggest that the paleo-water-depth in the Tongchuan area is deeper.The source rock could have the advance plants source,which must have close relationship with the Qinling orogeny.Comparing the paleoenvironment,the Tongchuan area has better depositional conditions,and is the key oil shale exploration area in the southern Ordos Basin. 展开更多
关键词 oil shale geochemistry depositional model Chang 7 Ordos Basin
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Bayesian prestack seismic inversion with a self-adaptive Huber-Markov random-field edge protection scheme 被引量:2
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作者 田玉昆 周辉 +2 位作者 陈汉明 邹雅铭 关守军 《Applied Geophysics》 SCIE CSCD 2013年第4期453-460,512,共9页
Seismic inversion is a highly ill-posed problem, due to many factors such as the limited seismic frequency bandwidth and inappropriate forward modeling. To obtain a unique solution, some smoothing constraints, e.g., t... Seismic inversion is a highly ill-posed problem, due to many factors such as the limited seismic frequency bandwidth and inappropriate forward modeling. To obtain a unique solution, some smoothing constraints, e.g., the Tikhonov regularization are usually applied. The Tikhonov method can maintain a global smooth solution, but cause a fuzzy structure edge. In this paper we use Huber-Markov random-field edge protection method in the procedure of inverting three parameters, P-velocity, S-velocity and density. The method can avoid blurring the structure edge and resist noise. For the parameter to be inverted, the Huber- Markov random-field constructs a neighborhood system, which further acts as the vertical and lateral constraints. We use a quadratic Huber edge penalty function within the layer to suppress noise and a linear one on the edges to avoid a fuzzy result. The effectiveness of our method is proved by inverting the synthetic data without and with noises. The relationship between the adopted constraints and the inversion results is analyzed as well. 展开更多
关键词 Huber edge punishment function markov random-field bayesian framework prestack inversion
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The Application of a Grey Markov Model to Forecasting Annual Maximum Water Levels at Hydrological Stations 被引量:12
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作者 DONG Sheng CHI Kun +1 位作者 ZHANG Qiyi ZHANG Xiangdong 《Journal of Ocean University of China》 SCIE CAS 2012年第1期13-17,共5页
Compared with traditional real-time forecasting,this paper proposes a Grey Markov Model(GMM) to forecast the maximum water levels at hydrological stations in the estuary area.The GMM combines the Grey System and Marko... Compared with traditional real-time forecasting,this paper proposes a Grey Markov Model(GMM) to forecast the maximum water levels at hydrological stations in the estuary area.The GMM combines the Grey System and Markov theory into a higher precision model.The GMM takes advantage of the Grey System to predict the trend values and uses the Markov theory to forecast fluctuation values,and thus gives forecast results involving two aspects of information.The procedure for forecasting annul maximum water levels with the GMM contains five main steps:1) establish the GM(1,1) model based on the data series;2) estimate the trend values;3) establish a Markov Model based on relative error series;4) modify the relative errors caused in step 2,and then obtain the relative errors of the second order estimation;5) compare the results with measured data and estimate the accuracy.The historical water level records(from 1960 to 1992) at Yuqiao Hydrological Station in the estuary area of the Haihe River near Tianjin,China are utilized to calibrate and verify the proposed model according to the above steps.Every 25 years' data are regarded as a hydro-sequence.Eight groups of simulated results show reasonable agreement between the predicted values and the measured data.The GMM is also applied to the 10 other hydrological stations in the same estuary.The forecast results for all of the hydrological stations are good or acceptable.The feasibility and effectiveness of this new forecasting model have been proved in this paper. 展开更多
关键词 Grey Markov Model forecasting estuary disaster prevention maximum water level
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Petrology, geochemistry and geodynamics of basic granulite from the Altay area, North Xinjiang, China 被引量:3
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作者 厉子龙 陈汉林 +2 位作者 杨树锋 董传万 肖文交 《Journal of Zhejiang University Science》 EI CSCD 2004年第8期979-984,共6页
The basic granulite of the Altay orogenic belt occurs as tectonic lens in the Devonian medium- to lower-grade metamorphic beds through fault contact. The Altay granulite (AG) is an amphibole plagioclase two-pyroxene ... The basic granulite of the Altay orogenic belt occurs as tectonic lens in the Devonian medium- to lower-grade metamorphic beds through fault contact. The Altay granulite (AG) is an amphibole plagioclase two-pyroxene granulite and is mainly composed of two pyroxenes, plagioclase, amphibole and biotite. Its melano-minerals are rich in Mg/(Mg+Fe2+), and its amphibole and biotite are rich in TiO2. The AG is rich in Mg/(Mg+Fe2+), Al2O3 and depletion of U, Th and Rb contents. The AG has moderate ∑REE and LREE-enriched with weak positive Eu anomaly. The AG shows island-arc pattern with negative Nb, P and Ti anomalies, reflecting that formation of the AG may be associated with subduction. Geochemical and mineral composition data reflect that the protolith of the AG is calc-alkaline basalt and formed by granulite facies metamorphism having peak P-T conditions of 750 °C?780 °C and 0.6?0.7 Gpa. The AG formation underwent two stages was suggested. In the early stage of oceanic crustal subduction, calc-alkaline basalt with island-arc environment underwent granulite facies metamorphism to form the AG in deep crust, and in the late stage, the AG was thrust into the upper crust. 展开更多
关键词 Basic granulite Petrology and geochemistry GEODYNAMICS Altay orogenic belt North Xinjiang
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Distribution and diversity of microbial communities in meromictic soda Lake Doroninskoe(Transbaikalia,Russia) during winter 被引量:3
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作者 Evgeniya MATYUGINA Natalia BELKOVA 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第6期1378-1390,共13页
Meromictic soda and saline lakes are unique ecosystems characterized by the stability of physical,chemical and biological parameters,and they are distributed all over the world.Lakes located in regions with average an... Meromictic soda and saline lakes are unique ecosystems characterized by the stability of physical,chemical and biological parameters,and they are distributed all over the world.Lakes located in regions with average annual negative air temperature are of particular interest because of the presence of two periods with intensive and dynamic processes:the so-called biological summer and the long ice season with the biological spring.Soda Lake Doroninskoe is located in Eastern Transbaikalia(51°14′N,112°14′E) in the permafrost zone in an extreme continental climate,and is covered by ice for seven months per year.The structure and diversity of the microbial communities throughout the water column of the lake was studied by 16 S r RNA gene amplicon metasequencing.Different species with specific functions were found to dominate at different depths.Metabolically flexible bacteria with a capacity to switch between anoxygenic photosynthesis and aerobic chemotrophic metabolism dominate in soda Lake Doroninskoe. 展开更多
关键词 bacterial diversity soda lake MEROMIXIS Lake Doroninskoe 16S rRNA genes high-throughput amplicon sequencing
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Review of studies on land use and land cover change in Nepal 被引量:9
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作者 Basanta PAUDEL ZHANG Yi-li +3 位作者 LI Shi-cheng LIU Lin-shan WU Xue Narendra Raj KHANAL 《Journal of Mountain Science》 SCIE CSCD 2016年第4期643-660,共18页
Land use and land cover(LULC) in Nepal has undergone constant change over the past few decades due to major changes caused by anthropogenic and natural factors and their impacts on the national and regional environmen... Land use and land cover(LULC) in Nepal has undergone constant change over the past few decades due to major changes caused by anthropogenic and natural factors and their impacts on the national and regional environment and climate.This comprehensive review of past and present studies of land use and land cover change(LUCC) in Nepal concentrates on cropland, grassland, forest, snow/glacier cover and urban areas. While most small area studies have gathered data from different sources and research over a short period, across large areas most historical studies have been based on aerial photographs such as the Land Resource Mapping Project in 1986. The recent trend in studies in Nepal is to focus on new concepts and techniques to analyze LULC status on the basis of satellite imagery, with the help of geographic information system and remote sensing tools. Studies based on historical documents, and historical and recent spatial data on LULC, have clearly shown an increase in cropland areas in Nepal,and present results indicating different rates and magnitudes. A decrease in forest and snow/glacier coverage is reported in most studies. Little information is available on grassland and urban areas from past research. The unprecedented rate of urbanization in Nepal has led to significant urban land changes over the past 30 years. Meanwhile, long term historical LUCC research in Nepal is required for extensive work on spatially explicit reconstructions on the basis of historical and primary data collection, including LULC archives and drivers for future change. 展开更多
关键词 Land use Land cover Geographic information system Remote sensing Nepal
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Prediction of Subtle Thin Gas Reservoir in the Loess Desert Area in the North of Ordos Basin 被引量:2
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作者 YangHua FuJinhua WangDaxing 《Applied Geophysics》 SCIE CSCD 2004年第2期122-128,共7页
For thin gas reservoir of low-porosity and low-permeability in the loess desert area, a suite of lateral reservoir prediction techniques has been developed by Changqing Oil Company and the excellent effects achieved i... For thin gas reservoir of low-porosity and low-permeability in the loess desert area, a suite of lateral reservoir prediction techniques has been developed by Changqing Oil Company and the excellent effects achieved in exploration and exploitation in the areas such as Yulin, Wushenqi,Suligemiao, Shenmu etc., so that the Upper Paleozoic gas reserve has been stably increasing for eight years in Changqing Oilfield. The paper analyzed the effects and experience of the application of these techniques in detail. 展开更多
关键词 DESERT nutralgas reservoir prediction seismic data processing AVO INVERSION MULTI-WAVE
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A review of the geomechanics aspects of a double fatality coal burst at Austar Colliery in NSW,Australia in April 2014 被引量:11
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作者 Hebblewhite Bruce Calvin Jim 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第1期3-7,共5页
A coal burst occurred on 15 April, 2014 at the Austar Coal Mine, located west of Newcastle, NSW,Australia. The burst resulted in fatal injuries to two men working as part of the mining crew at the development face. At... A coal burst occurred on 15 April, 2014 at the Austar Coal Mine, located west of Newcastle, NSW,Australia. The burst resulted in fatal injuries to two men working as part of the mining crew at the development face. At the time, a continuous miner was being used to mine a longwall development gate road through heavily structured coal, at a depth of approximately 550 m. A number of pre-cursor bumps had occurred on previous shifts, emanating from the coal ribs of the roadway, in proximity to the coal face.This paper reviews the geological, geotechnical and mining conditions and circumstances leading up to the coal burst event; and presents and discusses the available evidence and possible interpretations relating to the geomechanical behaviour mechanisms that may have been critical factors in this incident. The paper also discusses some key technical and operational considerations of ground support systems and mining practices and strategies needed for operating in such conditions in the future. 展开更多
关键词 Underground coal mining Roadway development Strata controlCoal burst Coal geology Mine safety
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Analyzing and Forecasting Climate Change in Harbin City,Northeast China 被引量:4
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作者 ZHANG Lijuan LIU Dong +3 位作者 YAN Xiaodong ZHOU Dongying ZHENG Hong SU Lianling 《Chinese Geographical Science》 SCIE CSCD 2011年第1期65-73,共9页
Based on sounding data from 1975 to 2005 and TM/ETM+ remote sensing images in 1989, 2001 and 2007, the climate changes in Harbin City, Northeast China in recent 30 years were analyzed and forecasted. Results show that... Based on sounding data from 1975 to 2005 and TM/ETM+ remote sensing images in 1989, 2001 and 2007, the climate changes in Harbin City, Northeast China in recent 30 years were analyzed and forecasted. Results show that in the lower troposphere the meridional wind speed and mean annual wind speed decrease, and in the lower stratosphere the temperature decreases while the meridional wind speed increases significantly. In the study area, the climate is becoming warmer and wetter in the middle lower troposphere. The expansion of urban area has great effects on the surface air temperature and the wind speed, leading to the increase of the surface air temperature, the decrease of the surface wind speed, and the increase of the area of urban high temperature zone. The quantitative equations have been established among the surface air temperature, the carbon dioxide (CO2) concentration and the specific humidity (the water vapor content). It is predicted that the future increasing rate of the surface air temperature is 0.85℃/10yr if emission concentration of CO2 remains unchanged; if emission concentration of CO2 decreases to 75%, 50% and 25%, respectively, the surface air temperature will increase 0.65℃/10yr, 0.46℃/10yr and 0.27℃/10yr, respectively. The rise of the surface air temperature in the study area is higher than that of the global mean temperature forecasted by IPCC. 展开更多
关键词 climate change climate forecast cause analysis Northeast China
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