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Geochemistry and Origin of Layers in Single Manganese Nodule from the Philippine Sea and Manganese Nodules from Offshore Minami-Torishima, Western Pacific 被引量:2
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作者 YAO Yungchang CHEN Juchin +1 位作者 HUH Chihan LEE Yungtan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第6期1835-1845,共11页
Layers from one manganese nodule dredged from the Philippine Sea(16°56'N, 129°48'E; water depth, 5700 m) and 45 bulk nodules from offshore Minami-Torishima Island, Japan(23°3'N, 153°22'E; wa... Layers from one manganese nodule dredged from the Philippine Sea(16°56'N, 129°48'E; water depth, 5700 m) and 45 bulk nodules from offshore Minami-Torishima Island, Japan(23°3'N, 153°22'E; water depth, 1200 m) were analyzed chemically and their origin is discussed based on geochemical constraints. In general, Cu, Ni, Zn and Mo tend to increase with increasing Mn content, while Co, Pb, Ba, V, Sc, Th, and the rare earth elements(REEs) show less variation with increasing Mn content. Nodule 42 H from the Philippine Sea has an average Mn/Fe ratio close to 1 and shows a positive Ce anomaly, suggesting a predominant hydrogenous origin. Profiles of 230Th230 ex and Thex/232 Th ratios in the outer ~0.3 mm of nodule 42 H indicate a steady growth rate of ~1.7 mm/Myr. Nodule E30 from offshore Minami-Torishima is characterized by lower Mn, Fe, Mn/Fe(0.53) and Mo/V(0.2) ratios but higher P and Cu/Ni(0.31) ratio relative to other nodules from that area. The Ce content of E30 is unusually low(82 ppm) when compared with other nodules from the area and it is the only nodule analyzed with a negative Ce anomaly(-0.64). Based on the geochemical data we suggest that most nodules from offshore Minami-Torishima are primarily of hydrogenous origin except E30, which is dominated by hydrothermal input, and E45, which has about a 35% hydrothermal contribution. 展开更多
关键词 manganese nodule geochemistry origin the Philippine Sea Minami-Torishima
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Geochemistry of Heavy Oil in the T Block,Oriente Basin and its Origin Mechanism 被引量:2
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作者 HU Ying YIN Jiquan SU Yongdi XIE Yinfu WANG Xiaoxia XIAO Gaojie YU Zhaohua WANG Li 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2010年第2期406-414,共9页
Exploration and development experience show that there is obvious oil gravity difference between the southern part and northern part of the "M1"reservoir in the Fanny oil field in the slope of the Oriente Basin, Ecu... Exploration and development experience show that there is obvious oil gravity difference between the southern part and northern part of the "M1"reservoir in the Fanny oil field in the slope of the Oriente Basin, Ecuador. The American Petroleum Institute Gravity (API) values of oils in the northern part are higher than the one in the southern part of the Fanny oil field, with the values of 20° and 10.0°-13.0°, respectively. So the primary purpose of this study was to analyze the heavy oil characteristics of biodegradation and the oil-oil correlation according to the biomarker data and the δ^13C signature of oil samples from T block. The results of the hydrocarbon gas chromatography fingermark and the inversion attribute characteristics indicated that there are fluid compartments between the "M1" reservoir of Fanny south. Finally, the models of oil-gas accumulation under the control of multiple-activities of complicated fault systems, as well as the origin of heavy oil, are contended. The early stage oils from the western part of the basin were biodegraded heavily in varying degrees in the whole basin, and the later stage oils were derived from the southern part in a large scale and were mature and lighter. Generally, oil mixing is the primary control of net oil properties, such as API gravity in Oriente Basin. We therefore predicted that the API gravity variation of oil pools radically depends on the injection amount of the later stage oil. Because of the shale barrier in the "M1"reservoir of Fanny south, the later stage hydrocarbon could not pass through and contribute to increase the oil API value. 展开更多
关键词 heavy oil geochemistry BIOMARKER origin mechanism Oriente Basin
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Origin of boron in the Damxung Co Salt Lake(central Tibet):Evidence from boron geochemistry and isotopes
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作者 Lü Yuanyuan ZHENG Mianping +4 位作者 CHEN Wenxi ZHANG Xuefei LIU Xifang WU Qian YU Jiangjiang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期151-152,共2页
The origin of boron in boron-rich salt lakes in the Tibetan Plateau has long been the subject of debate.The Damzung Co Salt Lake in central Tibet has high boron concentrations(B=276–313 mg/L)and is an ideal site for
关键词 Boron geochemistry origin Quaternary deposits Damxung Co Salt Lake TIBET
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Lithological and Si–O–S isotope geochemistry:constraints on the origin and genetic environment of the selenium(Se)-rich siliceous rocks in Enshi,Hubei Province,China
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作者 Caixia Feng Shen Liu Ian M.Coulson 《Acta Geochimica》 EI CAS CSCD 2021年第1期89-105,共17页
Se-rich black rock series of the Middle and Late Permian system is widely distributed in Enshi Prefecture with an exposed area of 850 km~2,among which the unique Yutangba black rock series independent selenium deposit... Se-rich black rock series of the Middle and Late Permian system is widely distributed in Enshi Prefecture with an exposed area of 850 km~2,among which the unique Yutangba black rock series independent selenium deposit with industrial mining significance in the world is produced.However,the source and metallogenic mechanisms of Se are still controversial.In general,terrestrial weathering and submarine hydrothermal processes are the main source end members of Si and Se,and the related siliceous rocks record the deposition process of Si and Se from different sources.The study of lithofacies and paleogeography shows that western Hubei belongs to the near eastwest turn of the Yangzi platform in the Middle and Late Permian and becomes an inter-platform basin with nearly north-south direction.Therefore,the comparative study of the Yutangba deposit and the selenium-rich black rock series in the northern Shadi with high selenium content is expected to reveal the provenance evolution of the two sections in space,and further restrict the Se mineralization mechanism in the Enshi basin.From the element geochemistry study,the black rock series in two study areas may have formed in a transitional position of either the continental margin or continental slope,in the process of sedimentary,more terrigenous clastic materials entered.They are rich in lithophile elements V and Cr.δU>1.0,U/Th and V/(V+Ni)ratio indicate that the Se-rich strata of black rock series in the Enshi areas occurred in an anoxic reducing environment and formed in an environment between the ocean basin and the continental margin.From Si-O isotope geochemistry,the original Si source of the study area is thought to relate to a volcanic eruption,which leads to the enrichment of Si in the seawater.The determined values of S isotope in the black rock series of the two study areas both show the characteristics related to organic reduction/biogenic. 展开更多
关键词 Se-rich siliceous rocks geochemistry Si–O–S isotope origin Sedimentary environment
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Study on Original Ecological Tridimensional Slope Vegetation 被引量:2
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作者 YAN Zhi-xin REN Zhi-hua +2 位作者 YAN Chang-ming JIANG Ping WANG Hou-yu 《Journal of Mountain Science》 SCIE CSCD 2013年第6期932-939,共8页
No matter from the perspective of slope protection, landscape effect and construction cost, or from the perspective of ecological benefit, the development of original ecological tridimensional vegetation has become th... No matter from the perspective of slope protection, landscape effect and construction cost, or from the perspective of ecological benefit, the development of original ecological tridimensional vegetation has become the inevitable trend for slope vegetation in pursuit of protecting ecological condition, decreasing soil erosion, maintaining ecological balance and beautifying environment of slope. The concept of original ecological tridimensional slope vegetation is proposed in this paper, and the original ecological tridimensional slope vegetation is studied through theoretical analysis and experiments. Specifically, the mechanical effect of slope vegetation in reinforcing the cohesion and shear strength of soil mass is firstly discussed, and then experiments are performed to study the water interception and containing function of slope under various vegetation conditions. Moreover, the relation between soil moisture and cohesion, the relation between root distribution density and cohesion, and the relation between root distribution density and soil shear strength are also studied based on experiments.Finally, based on field observation, the soil erosion states of slope under various vegetation conditions are comparatively studied. It is found that the original ecological tridimensional slope, which combines grass,shrub and tree, can generate comprehensive slope protection effects, and hence strengthen the slope protection ability and bring multiple slope protection benefits. Thereby, the theoretical foundation for developing original ecological tridimensional slope vegetation is established. 展开更多
关键词 植被护坡 生态要素 边坡植被 时空 保护生态环境 坡面土壤侵蚀 水土流失 抗剪强度
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Geochemistry and origin of gas pools in the Gaoqing-Pingnan fault zone, Jiyang Depression 被引量:1
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作者 SHEN Baojian HUANG Zhilong +3 位作者 LIU Hongwen XU Cheng YAN Zaifei CHEN Mi 《Chinese Journal Of Geochemistry》 EI CAS 2007年第4期446-454,共9页
In the surroundings of the Gaoqing-Pingnan fault zone are developed quite a number of gas reservoirs. Based on gas compositions, they can be divided into two groups, i.e., CO2 and CH4. Their composition and isotope ge... In the surroundings of the Gaoqing-Pingnan fault zone are developed quite a number of gas reservoirs. Based on gas compositions, they can be divided into two groups, i.e., CO2 and CH4. Their composition and isotope geochemistry were dealt with in this study. The CO2 contents range from 60.72%–99.99%, the δ13CCO2 values from -3.41‰– -9.8‰, and the 3He/4He ratios from 4.35×10-6–6.35×10-6 (i.e. R/Ra=4.45–4.35). Based on the data on composition and isotope geochemistry, deep geological background, deep faults and volcanic rocks, it is shown that CO2 ,distributed in the Gaoqing area, mostly originated from mantle-source inorganic matter which is associated with magmatic rocks. The favorable tectonic environment for the formation of CO2 reservoirs is the rift, which is related to great fault-magmatic activity, the formation of CO2 gas pools and their space-time correlation to the most recent magmatic activities. Hydrocarbon gas pools occur in the Huagou area. The CH4 contents are within the range of 88.83%–99.12%, and the δ13CCH4 values, -44.7‰– -54.39‰. This indicates that the hydrocarbon gas resulted from the decomposition of oil-type gas at high temperatures. Volcanic rocks in the CO2 gas pool-and CH4 gas pool-distributed areas show significant differences in Fe2O3 and FeO contents. This has proven that the hydrocarbon gas may have resulted from various chemical reactions. Magmatic activities are the primary reason for the distribution of CO2 and CH4 gas pools in the Gaoqing-Pingnan fault zone. 展开更多
关键词 气藏 地球化学 岩浆熔蚀 洼地
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Origin and geochemistry of Pan-African granitoid rocks in the Gabal Um Shomer area,Southwestern Sinai,Egypt 被引量:1
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作者 E1-Tokhi M.M. Musallum A. Amin B.M. 《Chinese Journal Of Geochemistry》 EI CAS 2009年第2期125-135,共11页
Geological, petrological and geochemical studies indicated that there are two distinct types of granitoid rocks: older quartz diorites to granodiorite assemblage and younger granitoids, the latter occurring in two pha... Geological, petrological and geochemical studies indicated that there are two distinct types of granitoid rocks: older quartz diorites to granodiorite assemblage and younger granitoids, the latter occurring in two phases. The older granitoids have a meta-aluminous chemistry and a calc-alkaline character, with high MgO, Fe2O3, TiO2, CaO, P2O5, Sr and low SiO2, K2O, and Rb. Their major and trace elements data, together with low 87Sr/ 86Sr ratios (0.7029±0.0008) are indicative of I-type affinities. The second- and third-phase granitoids range from calc-alkaline to alkaline, respectively. The second-phase granitoids have a peraluminous chemistry and high Sr, Ba, CaO, MgO, Al2O3 and Ti2O and low SiO2, K2O, Nb, Y and Rb relative to the third-phase granitoids. The corundum normative nature and field observations suggested that it was formed by partial melting of the lower crust. The third-phase granitoids are alkaline in nature and characterized by higher SiO2, Rb, Y, Nb and lower MgO, Sr and Ba values than the younger granitoids (phase Ⅱ). They are A-type granitoids which were generated from below or within the existing continental crust. 展开更多
关键词 花岗岩类岩石 地球化学 西奈半岛 过铝质花岗岩 起源 西南 埃及 石英闪长岩
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Types and Origin of Dolostones in Tarim Basin, Northwest China: Petrographic and Geochemical Evidence 被引量:12
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作者 CHEN Yongquan ZHOU Xinyuan +1 位作者 JIANG Shaoyong ZHAO Kuidong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第2期467-485,共19页
In the Tarim Basin of northwestern China hydrocarbon deposits have been discovered in parts of the thick strata of Cambrian dolostones. Based on petrographic study, six types of dolostone have been distinguished: Typ... In the Tarim Basin of northwestern China hydrocarbon deposits have been discovered in parts of the thick strata of Cambrian dolostones. Based on petrographic study, six types of dolostone have been distinguished: Type-l, pink mud-bearing silty crystalline dolostone (PMSD); Type-2, gypsum- and salt-bearing fine crystalline dolostone (GSFD); Type-3, fine crystalline dolostone with dolomite crystals with cloudy core and clear rim (CCFD); Type-4, deep gray mud-bearing silty crystalline dolostone (GMSD); Type-5, euhedral coarse crystalline dolostone (ECD); and Type-6, xenotopic coarse crystalline dolostone (XCD). Applying petrographic and geochemical methods, the genesis of the dolostones is studied in this paper. Normally, Type-I dolostone shows U- and Mo- depleted characteristics, reflecting a more oxidized formation environment; High ~80 and the purple color are consistent with formation of Sabkha dolostones on a supratidal flat. Types 2, 3, 4 dolostones show strata formation, similar REE patterns and 87Sr/86Sr ratios with contemporaneous limestones, suggesting a penecontemporaneous origin from seawater. Types 5 and 6 dolostones commonly occur as interbedded rocks, indicating secondary genesis after diagenesis. Type-6 dolostone has the highest order degree (OD) values (average 0.86), the lowest oxygen isotope values and positive Eu anomalies, which are consistent with previously reported hydrothermal dolostones. Differently, Type-5 shows euhedral texture, higher δ80 value, similar REE characteristic and 87Sr/86Sr ratios in comparison with contemporaneous limestones, suggesting that this type might have been dolomitized by down- transferring evaporated seawater during shallow burial stage. Dolostone fluid sources, formation environments and crystallizing dynamics are summarized and possible genetic models for the six types are proposed. 展开更多
关键词 DOLOMITE origin geochemistry PETROLOGY CAMBRIAN
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Origin, Age and Significance of Pseudotachylites from the Eastern Dabieshan Orogenic Belt, China 被引量:4
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作者 LIUJianmin DONGShuwen +2 位作者 ZHANGJiasheng LIUXiaochun CHENBailin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第1期52-60,共9页
Recent field survey in the eastern Dabieshan Mountains has revealed extensive occurrences of pseudotachylite. The pseudotachylite tends to occur as simple veins and injected networks along the NE-SW-trending fracture ... Recent field survey in the eastern Dabieshan Mountains has revealed extensive occurrences of pseudotachylite. The pseudotachylite tends to occur as simple veins and injected networks along the NE-SW-trending fracture zones or shear zones, which are parallel to the Tanlu fault zone and cut all the pre-Cretaceous geological bodies. The characteristics of both the microstructures gained by the optical microscope and SEM imaging and the geochemistry between the pseudotachylites and their host rocks show that the pseudotachylites were formed mainly by ultracataclasis of their wall rocks in which they occur. The bulk K-Ar ages of the pseudotachylites yielded a narrow range of 81 -93 Ma, and moreover the laser-probe 40Ar/39Ar dating of phengite overprinting on the pseudotachylite gave a weighted mean age of 78.9 Ma. These results show that the pseudotachylites from the eastern Dabieshan Mountains formed along the NE-SW-trending fault zone during the uplifting of the orogenic belt at 80-90 Ma, which places important constrains on the cooling and exhumation history of the Dabieshan Mountains during and after the late Cretaceous. 展开更多
关键词 PSEUDOTACHYLITE origin microstructure geochemistry age the eastern Dabieshan Mountains
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Origin of Paleofluids in Dabashan Foreland Thrust Belt:Geochemicai Evidence of ^(13)C,^(18)O and ^(87)Sr/^(86)Sr in Veins and Host Rocks 被引量:2
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作者 ZENG Jianhui XU Tianwu +1 位作者 SUN Zhanqiang ZHANG Yongwang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2010年第5期1239-1255,共17页
In the last ten years, with important discoveries from oil and gas exploration in the Dabashan foreland depression belt in the borderland between Shanxi and Sichuan provinces, the relationship between the formation an... In the last ten years, with important discoveries from oil and gas exploration in the Dabashan foreland depression belt in the borderland between Shanxi and Sichuan provinces, the relationship between the formation and evolution of, and hydrocarbon accumulation in, this foreland thrust belt from the viewpoint of basin and oil and gas exploration has been studied. At the same time, there has been little research on the origin of fluids within the belt. Based on geochemical system analysis including Z values denoting salinity and research on δ13C, δ18O and S7Sr/S6Sr isotopes in the host rocks and veins, the origin of paleofluids in the foreland thrust belt is considered. There are four principal kinds of paleofluid, including deep mantle-derived, sedimentary, mixed and meteoric. For the deep mantle-derived fluid, the δ13C is generally less than -5.0‰PDB, δ18O less than -10.0‰PDB, Z value less than 110 and 87Sr/86Sr less than 0.70600; the sedimentary fluid is mainly marine carbonate- derived, with the δ13C generally more than -2.0‰PDB, 18δO less than -10.0‰PDB, Z value more than 120 and STSr/S6Sr ranging from 0.70800 to 0.71000; the mixed fluid consists mainly of marine carbonate fluid (including possibly a little mantle-derived fluid or meteoric water), with the j13C generally ranging from -2.0‰ to -8.0‰PDB, δ18O from -10.0‰ to -18.0‰ PDB, Z value from 105 to 120 and 87Sr/86Sr from 0.70800 to 0.71000; the atmospheric fluid consists mainly of meteoric water, with the δ13C generally ranging from 0.0‰ to -10.0‰PDB, δ18O less than -8.0%rPDB, Z value less than 110 and 87Sr/86Sr more than 0.71000. The Chengkou fault belt encompasses the most complex origins, including all four types of paleofluid; the Zhenba and Pingba fault belts and stable areas contain a simple paleofluid mainly of sedimentary type; the Jimingsi fault belt contains mainly sedimentary and mixed fluids, both consisting of sedimentary fluid and meteoric water. Jurassic rocks of the foreland depression belt contain mainly meteoric fluid. 展开更多
关键词 paleofluid origin δ13C δ18O and 87Sr/S6Sr isotopic geochemistry Dabashan forelandthrust belt
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Mantle plume:the dynamic setting of the origin of Early Paleozoic mafic dykes in Ziyang,Shaanxi Province,Southern Qinling Block,China
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作者 Xiaoqing Chen Shen Liu +5 位作者 Caixia Feng Ian M.Coulson Yan Fan Kairui Tai Tianjing Gao Siyuan Zhang 《Acta Geochimica》 EI CAS CSCD 2020年第3期307-325,共19页
The mafic dykes(dolerites)during the Early Paleozoic are widely spread in Langao-Ziyang,southern Qiling Block,and the investigation on these dykes are very important.Previous studies have mainly focused on the Siluria... The mafic dykes(dolerites)during the Early Paleozoic are widely spread in Langao-Ziyang,southern Qiling Block,and the investigation on these dykes are very important.Previous studies have mainly focused on the Silurian mafic dykes;however,research on the Earlier Paleozoic mafic dykes is relatively weak at present.Therefore,the overall understanding of the mantle source and genetic dynamic setting during the Early Paleozoic in this area is lacking.To study the accurate age and origin of the Early Paleozoic mafic dykes in Ziyang,southern Shaanxi Province,the mafic dykes from dabacunand Qinmingzhai were selected and the petrology,zircon U-Pb chronology,geochemistry,and Sr-Nd-Hf isotopes were studied.Analysis indicates that the mafic dykes studied are mainly composed of dolerite,and they are the products of the Early Ordovician(475.8-480.7 Ma).Furthermore,the dolerites belong to alkaline rock series,and they are characterized by enrichment in LREE,Rb,Ba,Sr,Nb,(87Sr/86Sr)i=0.7020-0.7050,εNd(t)=3.0-4.0),εHf(t)=4.5-12.1,176Hf/177Hf=0.282681-0.282844.This suggests that the mafic dyke were derived from the partial melting of a depleted lithospheric mantle,and the genetic process is mainly controlled by the mantle plume based on the discussion of the genetic model.Furthermore,the genetic process experienced the separation and crystallization of olivine and clinopyroxene at the same time,with little crustal contamination. 展开更多
关键词 Early Paleozoic DOLERITES geochemistry origin Mantle plume
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Zircon U–Pb dating,geochemical,and Sr–Nd–Pb–Hf isotopic constraints on the age and origin of intermediate to felsic igneous rocks at South Altyn,Xinjiang,China
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作者 Shen Liu Caixia Feng +4 位作者 Yan Fan Xiaoqing Chen Yuhong Yang Huibo Zhao Ian M.Coulson 《Acta Geochimica》 EI CAS CSCD 2020年第5期698-716,共19页
As a part of a giant trending fault system in the Asian continent and one where a strong zone of left strikeslip fault is present,the Altyn Orogenic belt(AOB)has become an important focus for research.Magmatic rocks a... As a part of a giant trending fault system in the Asian continent and one where a strong zone of left strikeslip fault is present,the Altyn Orogenic belt(AOB)has become an important focus for research.Magmatic rocks are widely distributed across the AOB.However,many investigations have focused primarily on Paleozoic igneous rocks;discussion of Mesozoic related igneous activity is often ignored.Here we present the result of studies of representative diorite and granite rocks outcropping in the AOB,within the Xinjiang Uygur Autonomous Region,South Altyn,China.We present new zircon LA-ICP-MS U-Pb age,geochemical,and Sr-Nd-Pb-Hf isotopic data for these sample suites,identifying them as typical igneous rocks formed between 238±1.5 and 238.8±1.1 Ma.The rocks that we studied fall into the alkaline series,also enriched in light rare earth elements(LREE),some large ion lithophile elements(LILE;e.g.,Rb,Ba,Sr,and K),Pb,Th and U,and depleted in heavy rare earth elements(HREE),Nb,Ta,Hf,and Ti.The granite and diorite have high initial 87Sr/86Sr ratios(0.7062-0.7114),negativeεNd(t)values(-8.8 to-11.3),εHf(t)values(-8.7 to-18.7),and relatively constant Pb isotopic ratios((206-Pb/204Pb)i=6.74-17.884,(207Pb/204Pb)i=15.51-15.58,and(208Pb/204Pb)i=35.36-38.04),respectively.This suggests that the magmas parental to these rocks were generated from the partial melting of the ancient crust.The parental magmas to these rocks experienced a degree of fractionation of plagioclase,K-feldspar,and hornblende,possibly during rapid magma ascent.Based on these studies,we propose a reasonable model for the origin of the investigated rocks from the Xinjiang Uygur Autonomous Region of South Altyn,which involves crustal thickening,lithospheric extension,and asthenosphere upwelling,that induced crustal melting. 展开更多
关键词 Altyn orogenic belt Zircon U–Pb dating geochemistry Sr–Nd–Pb–Hf isotope origin
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Molecular Geochemical Evidence for the Origin of Natural Gas from Dissolved Hydrocarbon in Ordovician Formation Waters in Central Ordos Basin 被引量:7
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作者 李贤庆 侯读杰 +2 位作者 唐友军 胡国艺 熊波 《Chinese Journal Of Geochemistry》 EI CAS 2003年第3期193-202,共10页
Having studied the biomarker composition and maturity of dissolved hydrocarbons from Ordovician formation waters, the authors presented molecular geochemical evidence for the controversial origin of natural gases in c... Having studied the biomarker composition and maturity of dissolved hydrocarbons from Ordovician formation waters, the authors presented molecular geochemical evidence for the controversial origin of natural gases in central Ordos Basin.The dissolved hydrocarbons in Well Shan 12 and Well Shan 78 are relatively high in abundance of tricylic terpane, pregnane series and dibenzothiophene series and low in Pr/Ph and hopane/sterane ratios, indicating the source input of marine carbonates. In contrast, the dissolved hydrocarbons in Well Shan 81 are free from tricyclic terpane and pregnane series, with trace dibenzothiophene series and high Pr/Ph and higher hopane/sterane ratios, which are the typical features of terrestrial organic matter. Furthermore, Well Shan 37 and Well Shan 34 are between the two situations, having a mixed source of marine carbonate and terrestrial organic matter. The maturity of biomarkers also supports the above suggestions. These results are consistent with the geological background and source rock distribution in this region. 展开更多
关键词 分子地球化学 天然气 成因 奥陶纪 液化烃 Ordos盆地
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Environmental geochemistry and ecological risk of vanadium pollution in Panzhihua mining and smelting area, Sichuan, China 被引量:9
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作者 滕彦国 倪师军 +3 位作者 张成江 王金生 林学钰 黄艺 《Chinese Journal Of Geochemistry》 EI CAS 2006年第4期378-384,共7页
Vanadium is a trace element widely distributed in the Earth’s crust. Naturally high levels of vanadium are recognized mainly in basic rocks and minerals, particularly in titaniferous magnetite. And the anthropogenic ... Vanadium is a trace element widely distributed in the Earth’s crust. Naturally high levels of vanadium are recognized mainly in basic rocks and minerals, particularly in titaniferous magnetite. And the anthropogenic sources of vanadium include fossil fuel combustion and wastes including steel-industry slags. In the last few years, the authors have made investigations and assessments on the environmental geochemistry and ecological risk of vanadium in the Panzhihua mining and smelting area. In the study area, anthropogenic vanadium resulted from mining, extracting and smelting of V-Ti magnetite; vanadium pollution of topsoil and sediments occurs mainly in the mining and extracting area, smelting area, slag dumping area, tailing dam and coal mining area. In the soil, the chemical speciation of vanadium shows: insoluble residue > organically bound > Fe (amorphous) oxide-bound > Mn oxide-bound > soluble component. Vanadium pollution can cause potential harmful effects on ecological systems, and lead to animal poisoning and human disease. So vanadiam pollution should be monitored on a regular basis in the Panzhihua area. 展开更多
关键词 环境地球化学 生态风险 地壳
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马克思主义生态政治学视域下习近平生态文明思想的原创性贡献
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作者 李全喜 李培鑫 《中国地质大学学报(社会科学版)》 北大核心 2024年第4期1-10,共10页
西方生态政治学是特定西方语境下政治社会变革和学术话语塑造的结果,马克思主义生态政治学破解了西方生态政治学对生态政治现象的意识形态遮蔽,是一种兼具科学性与意识形态性的知识体系。习近平生态文明思想基于新时代中国特色社会主义... 西方生态政治学是特定西方语境下政治社会变革和学术话语塑造的结果,马克思主义生态政治学破解了西方生态政治学对生态政治现象的意识形态遮蔽,是一种兼具科学性与意识形态性的知识体系。习近平生态文明思想基于新时代中国特色社会主义生态文明建设的实践经验提出诸多新思想新观点新论断,以一系列原创性成果促进了马克思主义生态政治学中国化时代化理论创新,充分彰显出构建中国自主生态政治学理论的自信与自觉。其原创性贡献表现为:在社会主义原则下推进生态文明建设,深刻揭示了生态政治的本质规定;坚持党对生态文明建设的全面领导,牢牢把握了生态政治的根本保证;紧紧依靠人民群众的力量推进生态文明建设,准确界定了生态政治的实践主体;始终坚持将生态文明建设作为“国之大者”,科学谋划了生态政治的战略布局;共谋全球生态文明建设,拓宽了生态政治的全球视野。从学术史层面梳理习近平生态文明思想对马克思主义生态政治学的原创性贡献,可以为当下理解和把握习近平生态文明思想的鲜明政治品格提供学理支撑,并推动生态政治学“从西方到东方”的研究转向。 展开更多
关键词 马克思主义生态政治学 习近平生态文明思想 社会主义生态文明 原创性贡献
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原生态色彩在皮革产品创意设计中的应用
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作者 张丽媛 闫维 《中国皮革》 CAS 2024年第2期140-143,共4页
随着社会的不断变化和发展,染色技术达到了很高的水平,各式各样的颜色能够让消费者选择更多。其中,原生态色彩取材自大自然,在色彩稳定方面具有优势,长时间观看也赏心悦目。因此,在皮革产品创意设计中,原生态色彩愈发凸显其重要地位。... 随着社会的不断变化和发展,染色技术达到了很高的水平,各式各样的颜色能够让消费者选择更多。其中,原生态色彩取材自大自然,在色彩稳定方面具有优势,长时间观看也赏心悦目。因此,在皮革产品创意设计中,原生态色彩愈发凸显其重要地位。本文从原生态色彩出发,分析了基于原生态色彩理念的皮革产品设计,并介绍了原生态色彩在皮革产品设计中的应用。原生态色彩在皮革产品创意设计中应用广泛。如果正确应用,必将推动皮革产品的创意设计。 展开更多
关键词 原生态色彩 皮革产品 创意设计
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美育思政语境下高校原创文化精品“生态化”传播探微
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作者 郑萌 《中州大学学报》 2024年第2期93-96,共4页
高校原创文化精品,是创新性美育思政教育的重要载体之一。由于种种原因,文化精品常常传播力度甚微,没有充分发挥应有的价值。在此运用符合自然生态规律的方法,构建科学的“生态化”传播路径,即严控原创文化精品“产出”的遴选标准,确保... 高校原创文化精品,是创新性美育思政教育的重要载体之一。由于种种原因,文化精品常常传播力度甚微,没有充分发挥应有的价值。在此运用符合自然生态规律的方法,构建科学的“生态化”传播路径,即严控原创文化精品“产出”的遴选标准,确保作品“思想精深、艺术精湛、制作精良”;优化原创文化精品的“存活”环境,为文化精品传播提供可循环、可持续发展的绿色通道;完善原创文化精品的“评价”体系,实施原创文化精品的“修复”机制,通过吸收、内化、改造,直至丰富和发展成果内容;开拓原创文化精品的“转化”模式,扩大成果效益,实现最大化的成果价值。 展开更多
关键词 美育思政 原创文化精品 “生态化”
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松辽平原典型黑土区不同土壤结构的古气候背景与黑土成因机制
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作者 刘航 李瑞红 +5 位作者 李胜荣 侯红星 秦天 高远 周业泽 李明军 《地质通报》 CAS CSCD 北大核心 2024年第5期766-778,共13页
黑土成因机制研究是理解黑土形成演化过程的基础,更是加强黑土地保护和可持续利用的关键。以松辽平原典型黑土区吉林梨树县LZK-4钻孔为研究对象,基于粘土矿物学、元素地球化学、^(14)C、光释光测年等手段,重建了梨树县晚更新世中期以来... 黑土成因机制研究是理解黑土形成演化过程的基础,更是加强黑土地保护和可持续利用的关键。以松辽平原典型黑土区吉林梨树县LZK-4钻孔为研究对象,基于粘土矿物学、元素地球化学、^(14)C、光释光测年等手段,重建了梨树县晚更新世中期以来的古气候演化序列,揭示不同土壤类型的古气候背景,解析了典型黑土的气候成因机制。结果表明:①研究区典型黑土形成于晚全新世,底界年龄为2452 cal.a BP;②LZK-4钻孔揭示了黑土层—灰白色粘土层—褐黄色粘土层的垂向结构,气候总体变化趋势由温湿向干冷转化;③研究区典型黑土主要形成于晚全新世寒冷干旱的气候条件。本研究有助于理解松辽平原梨树地区典型黑土的形成演化过程,为黑土资源的开发、利用和保护提供科学依据。 展开更多
关键词 松辽平原 粘土矿物 元素地球化学 古气候 黑土成因 环境地质调查工程
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想象哲学及其对儿童想象生态建构的启示 被引量:1
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作者 苗雪红 《学前教育研究》 北大核心 2024年第2期11-20,共10页
想象作为人类重要的精神活动,长期以来未能受到应有的重视,甚至在很大程度上人们对想象存在贬视和误解。在柏拉图开启的西方理性主义身心二元论传统中,想象被视为最低等级的心灵状态,是感性与知性之间的中介。康德提出了想象力作为“先... 想象作为人类重要的精神活动,长期以来未能受到应有的重视,甚至在很大程度上人们对想象存在贬视和误解。在柏拉图开启的西方理性主义身心二元论传统中,想象被视为最低等级的心灵状态,是感性与知性之间的中介。康德提出了想象力作为“先验”能力的新概念,使想象从逻辑上成为经验建构的潜在基础。在整个20世纪,胡塞尔开启的现象学想象哲学从更广泛的本体论意义上对想象进行了较为彻底的研究,将想象视为一种呈现和创造现实的构成性力量。巴什拉和梅洛-庞蒂突破意识哲学,通过考察儿童时期身体与世界原初接触时的物质(元素)想象开辟了想象本体论的新路径。儿童想象是身体与周围世界建立原初的深层互动关系并不断生成意义的过程,这个过程也是人对世界陷入更深层次的情感关涉的过程,想象因此成为一种与世界相亲的存在方式。这些研究启发我们,儿童教育亟须确立想象的本体论价值取向,守护儿童想象的时空,支持儿童游戏对想象的生动呈现,从而为儿童建构良好的想象生态。 展开更多
关键词 身体 感知 想象 儿童想象 原初经验 想象生态
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海南霸王岭不同起源林分森林群落特征及乔木碳储量研究
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作者 皮志豪 刘宏伟 +2 位作者 王旭 李新建 宋希强 《湖南林业科技》 2024年第3期19-26,35,共9页
热带森林因具有很高的生物多样性和强大的生态服务功能而成为全球生态学研究的热点。然而,针对不同林分起源森林群落特征和碳储量之间的差异的研究报道却比较少见。本研究以海南霸王岭林区人工促进更新次生林(PF)、天然次生林(SF)和原始... 热带森林因具有很高的生物多样性和强大的生态服务功能而成为全球生态学研究的热点。然而,针对不同林分起源森林群落特征和碳储量之间的差异的研究报道却比较少见。本研究以海南霸王岭林区人工促进更新次生林(PF)、天然次生林(SF)和原始林(VF)3种不同起源的林分为研究对象,针对其群落的物种组成、群落结构、生物量和碳储量进行差异性分析,结果表明:(1)物种的丰富度大小为VF>SF>PF,径级分布均呈反“J”字型,表现为更新层>演替层>主林层的稳定的群落结构;(2)3种起源的林分乔木生物量大小排序依次均为:干>根>枝>叶,各生物量在径级分布上存在差异,PF、SF和VF各径级的生物量排序分别为Ⅱ>Ⅲ>Ⅰ>Ⅳ,Ⅳ>Ⅱ>Ⅲ>Ⅰ和Ⅳ>Ⅲ>Ⅱ>Ⅰ;(3)3种林分的乔木碳储量为105.01~199.47 t.hm^(-2),其中原始林碳储量最大,人工促进更新次生林最小,人工促进更新次生林乔木碳储量主要分布在径级Ⅱ的树木中,天然次生林乔木碳储量主要分布在径级Ⅱ和Ⅳ的树木中,原始林乔木碳储量主要分布在径级Ⅳ的树木中。研究结果可为热带林业经营管理、森林碳监测和评估提供理论支撑。 展开更多
关键词 热带森林 生物量 碳转化系数 群落生态 林分起源 碳储量
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