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Regulation mechanism of EM parameters in natural ferrite and its application in microwave absorbing materials

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Science China(Technological Sciences) 2006年第1期49卷 38-49页

作者： ZHENG Yongchun1,2. WANG Shijie2. FENG Junming2. LI Chunlai1, OUYANG Ziyuan1,2. LIU Jianzhong1 & LI Xiaobiao2.1. National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012. China 2. State key laboratory of Environmental {2., Institute of {2., Chinese Academy of Sciences, Guiyang 550002. China 1. National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China 2. State key laboratory of Environmental {2. Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

Electromagnetic (EM) parameters (ε ′, ε ″, μ ′, μ″ ) of several M2.Fe2.4 and Fe2.3 type natural ferrites with different geological occurrences are measured in this pa-per. The measurement results show that EM parameters of a magmatic-occurring natural ferrite is very different from other types occurring from sedimentary-metamorphic iron deposit, hydrothermal vein iron deposit, outer contact of magmatic iron deposit. It has potential to be used as magnetic absorbent in microwave absorbing materials. After min-eral separation and concentration, this magmatic-occurring natural ferrite was processed into type A ferrite absorbent. Type A natural ferrite absorbent is a kind of magnetic material with low dielectric constants, high magnetic conductivity and high EM loss. Its EM pa-rameters are ε ′ = 58.60, ε ″ = 10.0, μ ′ = 1.2.1.5, μ ″ = 1.0-1.2. respectively. In order to illuminate the regulation mechanism of EM parameters, we studied the chemical and mineral composition of type A ferrite absorbent. There is high concentration of natural impurities, which regulate the EM parameters of type A ferrite greatly. For comparison, the other types of natural ferrite, single-phase magnetite and two-phase iron minerals (ilmen-ite and magnetite), have few impurity. Thus regulation mechanism of EM parameters was absent in these ferrites. As a result, the regulation of EM parameters is advantageous to develop type A natural ferrite as excellent absorbent, lowers the reflectivity coefficients and enhances the absorbing efficiency of MAM made from it. Furthermore, the impurities in type A natural ferrite and its effects on EM parameters are very difficult to simulate in the synthesize ferrite. The carbonyl-iron powder is another kind of absorbent that is used ex-tensively in MAM. To compare the absorbing properties of these two absorbent, type A natural ferrite and carbonyl-iron powder were mixed with rubber and processed into mi-crowave absorbing sheets with the same procedures and tec

关键词： natural impure ferrite, complex permittivity, complex permeability, microwave absorbing materials.

Geochronology and geochemistry of Ore-related Granitoids in the Giant Gariatong Rb Deposit,Tibet and Implications for Rb Metallogeny in China

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 83-103页

作者： LIN Bin TANG Juxing TANG Pan SUN Yan QI Jing MSANTOSH XIE Jinling DENG Shilin LI Faqiao XIE Fuwei ZHOU Aorigele MNR key laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China SinoProbe laboratory Chinese Academy of Geological SciencesBeijing 100094China The key laboratory of the Ministry of Education on Solid Waste Treatment and Recycling School of Environment and ResourceSouthwest University of Science and TechnologyMianyangSichuan 621010China School of Earth Sciences and Resources China University of Geosciences(Beijing)Beijing 100083China Department of Earth Sciences University of AdelaideAdelaide SA-5005Australia Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengdu 610031China Regional Geological Survey Team of the Tibetan Bureau of Geology and Mineral Exploration and Development Lhasa 851400China College of Earth Science and key laboratory of Tectonic Controlled Mineralization and Oil Reservoirs Chengdu University of TechnologyChengdu 610059China

Rubidium(Rb)deposits mostly occur in the South China and Central Asia orogenic belts and are often closely associated with highly differentiated *** study investigates a newly-discovered giant Rb deposit at Gariatong in the Central Lhasa terrane in *** field studies and logging data revealed that the Rb mineralization mainly occurs in monzogranite and is related to ***-ICP-MS U-Pb dating of zircon yielded ages of 19.1±0.2.Ma and 19.0±0.2.Ma for greisenized monzogranite and fresh monzogranite,*** monzogranites are characterized as strongly peraluminous,with high contents of SiO2.Al2.3,K2. and Na2. as well as a high differentiation *** are enriched in light rare earth and large ion lithophile elements with significant negative Eu anomalies and depleted high fieldstrength *** and geochemical features of these ore-related monzogranites suggest that they are highly fractionated S-type granites,derived from remelting of crustal materials in a post-collisional *** geochemistry of zircon and apatite points to a low oxygen fugacity of the ore-related monzogranite during the magma’s *** discovery of the Gariatong Rb deposit suggests that the Central Lhasa terrane may be an important region for rare metal mineralization.

关键词： LA-ICP-MS U-Pb dating geochemistry Rb metallogeny Gariatong Tibet

Distribution of Helium Isotopes in Western Pacific Upper Layer

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Science China Chemistry 1994年第3期37卷 344-352页

作者：任建国王先彬 State key laboratory of {2. geochemistry Lanzhou Institute of Geology Academia SinicaLanzhou 730000 PRC

3He/4He ratios in samples of sea water obtained at depths from surface to 300 m in the upper layer of the Western Pacific Ocean were measured by a mass spectrometer VG5400. The lateral and vertical distribution of He isotopes in the studied area was discussed in detail on the basis of 3He/4He ratios. Excess and depleted 3He. in relation to δ3He value of surface water in equilibrium with air has been discussed in the area, which may be mainly attributed to the incorporation of the North Pacific Intermediate Water with the Equatorial Upwelling and the exchange of water masses between the South China Sea and the Western Pacific, respectively. The present work in Western Pacific has also indicated that He isotopes may be used as a tracer for mixing processes of water masses and oceanic circulation.

关键词： Western Pacific upper layer water distribution of He isotopes mixing of water masses.

Mineral Chemistry,Trace Elements,Isotopic Analysis and Zircon U-Pb Dating in the Hesar Pluton,Northern UDMA,Iran:Implications for Pre-Collisional Magma Mixing

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 657-678页

作者： Kazem KAZEMI Soroush MODABBERI Parisa GHARIBNEJAD XIAO Yilin Fatemeh SARJOUGHIAN Ali KANANIAN School of Geology College of ScienceUniversity of TehranTehranIran Research Centre for Mineral Resources Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China National key laboratory of Ecological Security and Resource Utilization in Arid Areas Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Department of geochemistry and Environmental Sciences School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China Department of Earth and Sciences Faculty of SciencesUniversity of KurdistanSanandajIran Department of Science Education Farhangian UniversityTehranIran

The Hesar pluton in the northern Urumieh-Dokhtar magmatic arc hosts numerous mafic-microgranular enclaves(MMEs).Whole rock geochemistry,mineral chemistry,zircon U-Pb and Sr-Nd isotopes were *** is suggested that the rocks are metaluminous(A/CNK=1.32.1.45),subduction-related I-type calc-alkaline gabbro to diorite with similar mineral assemblages and geochemical *** host rocks yielded an U-Pb crystallization age of 37.3±0.4 Ma for *** have relatively low SiO_(2. contents(52.9-56.6 wt%)and high Mg^(#)(49.8-58.7),probably reflecting a mantle-derived ***-and mantle-normalized trace element patterns are characterized by LREE and LILE enrichment,HREE and HFSE depletion with slight negative Eu anomalies(Eu/Eu^(*)=0.86-1.03).The host rocks yield(^(87)Sr/^(86)Sr)_(i) ratios of 0.70492.0.70510,positive ε_(Nd)(t)values of+1.55-+2.06 and T_(DM2.of 707-736 Ma,which is consistent with the associated mafic microgranular enclaves((^(87)Sr/^(86)Sr)_(i)=0.705014,ε_(Nd)(t)=+1.75,T_(DM2.=72. Ma).All data suggest magma-mixing for enclave and host rock formation,showing a complete equilibration between mixed-mafic and felsic magmas,followed by rapid *** T_(DM1)(Nd)and T_(DM2.(Nd)model ages and U-Pb dating indicate that the host pluton was produced by partial melting of the lower continental crust and subsequent mixing with injected lithospheric mantlederived magmas in a pre-collisional setting of Arabian-Eurasian *** composition indicates a crystallization temperature of~1000℃ and a depth of~9 km.

关键词： enclave magma mixing zircon U-Pb dating Urumieh-Dokhtar magmatic arc

Magmatic-tectonic response of the South China Craton to the Paleo-Pacific subduction during the Triassic:a new viewpoint based on Well NK-1

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Journal of Oceanology and Limnology 2024年第1期42卷 58-89页

作者： Chan WANG Hao LIU Gang LI Zhen SUN Tingting GONG Li MIAO Xiaowei ZHU Yunying ZHANG Weihai XU Wen YAN key laboratory of Ocean and Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Southern Marine Science and Engineering Guangdong laboratory(Guangzhou) Guangzhou 511458China key laboratory of Tectonic Controlled Mineralization and Oil Reservoir of Ministry of Natural Resources Chengdu University of TechnologyChengdu 610059China School of Earth Sciences and Resources China University of Geosciences(Beijing)Beijing 100083China College of Earth Science Chengdu University of TechnologyChengdu 610059China University of Chinese Academy of Sciences Beijing 100049China

The Nansha Block(NB)is one of the blocks separated from the southern margin of the South China Craton(SCC)by the western Pacific subduction,which contains rich information of geodynamic and tectonic *** reveal the essence of western Paleo-Pacific subduction during the Triassic period,Well NK-1 in this block was selected for petrographic study,and published research data from other cooperative teams were compared.A double-cycle pattern of basic to neutral magmatic volcanism was established,and 36 lithological rhythmic layers and representative cryptoexplosive breccia facies and welded tuff bands were *** with a reanalysis of published geochronological data,geochemical elements,and isotope geochemistry,we found that the rock assemblages could be divided into an intermediate-acid dacite(DA)series(SiO_(2.>65%)and basaltic(BA)series(Co2.8.6±3.2.–(2.7.9±3.5)Ma).BA exhibits obvious calc-alkaline island-arc magmatic properties:(^(87)Sr/^(86)Sr)_i ratio ranging 0.70377–0.71118(average:0.70645),^(147)Sm/^(144)Nd ratio ranging 0.119–0.193(average:0.168),and chondrite-normalized rare earth element(REE)curves being flat,while DA exhibits remarkable characteristics of subducted island-arc andesitic magma:(^(87)Sr/^(86)Sr)_i ratio(0.70939–0.7112.;average:0.71035),εNd(t)value(-6.2.-4.8;average:-5.6)andε_(Hf)(t)value(-2.9–-1.7,average:-2.2.show obvious crust-mantle mixing *** and DA reveal typical characteristics of island-arc magma systems and typeⅡenriched mantle(EM-Ⅱ)*** magma was likely resulted from the process whereby the continental crust frontal accretionary wedge was driven by the Paleo-Pacific slab subduction into the deep and began to melt,resulting in a large amount of melt(fluid)joined the asthenosphere on the side of the continental *** contrast,DA magma was likely resulted from the process whereby the plate front was forced to bend with increasing subducti

关键词： Paleo-Pacific tectonic domain tectonic evolution rift volcanic rock Nansha Block South China Craton

Sources, enrichment mechanisms, and resource effects of rare metal elements-enriched geothermal springs in Xizang, China

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Science China Earth Sciences 2024年第11期67卷 3476-3499页

作者： Fei XUE Hongbing TAN Xiying ZHANG Jinbao SU School of Earth Sciences and Engineering Hohai University Qinghai Provincial key laboratory of Geology and Environment of Salt Lakes Qinghai Institute of Salt Lakes Chinese Academy of Sciences School of Oceanology Hohai University

Rare metals such as lithium(Li), rubidium(Rb), and cesium(Cs) are strategically crucial mineral resources for the development of emerging industries in China. Ensuring a stable long-term supply of these resources is essential. The geothermal systems in Xizang, China are well-developed, with a wide distribution of various types. Most high-temperature geothermal systems in Xizang are exceptionally enriched in rare metal elements(RMEs) and have the potential to become a new source of rare metals to secure China's strategic mineral resource supply in the future. A close relationship also exists between the geothermal system and the special salt lake resources on the Tibetan Plateau. Geothermal springs thus play a key role in the migration and enrichment of RMEs from deep to shallow parts of the crust, in the transition between endogenous and exogenous mineralization, and source-to-sink processes. However, the mechanisms of element enrichment and evolution in these springs have not been systematically discussed, and many theoretical issues remain to be investigated. Based on summarizing and analyzing previous research, this study employs hydrochemical and isotopic geochemistry methods to investigate typical geothermal springs across Xizang and explore the anomalous enrichment mechanism of RMEs, and the resource effects of geothermal springs. Comprehensive analysis shows that the total dissolved solids(TDS) and hydrochemical types of geothermal springs are similar to those of major geothermal fields worldwide, but the Tibetan springs are abnormally rich in Li(averaging5.48 mg/L), Rb(averaging 0.75 mg/L), and Cs(averaging 3.58 mg/L), which are hundreds to thousands of times more concentrated than natural waters. The distribution of these enriched geothermal springs is controlled by the Yarlung Zangbo suture zone and the extended N-S trending rifts, especially in the intersection zone of the two, where the geothermal springs are the most enriched. Based on the spatial distr

关键词： Geothermal springs Rare metal elements Enrichment mechanisms Salt lakes Tibetan Plateau

Hydrocarbon Generation Potential and Organic Matter Enrichment Mechanism of the Cambrian Marine Shale in the Tadong Low Uplift, Tarim Basin

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ACTA GEOLOGICA SINICA-ENGLISH EDITION 2024年第5期98卷 1301-1321页

作者： Miao, Huan Wang, Yanbin Jiang, Zhenxue Zhao, Shihu Shang, Peng Gong, Xun Tao, Chuanqi Zhang, Yu China Univ Petr Natl Key Lab Petr Resources & Engn Beijing 102249 Peoples R China China Univ Petr Unconvent Oil & Gas Sci & Technol Res Inst Beijing 102249 Peoples R China China Univ Min & Technol Coll Geosci & Surveying Engn Beijing 100083 Peoples R China SINOPEC Petr Explorat & Prod Res Inst Beijing 102206 Peoples R China PetroChina Changqing Oilfield Co Gas Prod Plant 2 Yulin 719000 Shaanxi Peoples R China Peking Univ Sch Earth & Space Sci Beijing 100871 Peoples R China Liaoning Petrochem Univ Sch Civil Engn Fushun 113001 Liaoning Peoples R China

Cambrian shales in China and elsewhere contain abundant oil and gas resources. However, due to its deep burial and limited outcrop, there has been relatively little research conducted on it. The Cambrian shale of the Tadong low uplift in the Tarim Basin of western China, specifically the Xidashan-Xishanbulake Formation (Fm.) and overlying Moheershan Fm. provide a case study through the use of organic petrology, mineralogy, organic and elemental geochemistry, with the aim of analyzing and exploring the hydrocarbon generation potential (PG) and organic matter (OM) enrichment mechanisms within these shale formations. The results indicate that: (1) the Cambrian shale of the Tadong low uplift exhibits relatively dispersed OM that consists of vitrinite-like macerals and solid bitumen. These formations have a higher content of quartz and are primarily composed of silica-based lithology; (2. shale samples from the Xidashan-Xishanbulake and Moheershan formations demonstrate high total organic carbon (TOC) and low S-2.content. The OM is predominantly type I and type II kerogens, indicating a high level of maturation in the wet gas period. These shales have undergone extensive hydrocarbon generation, showing characteristics of relatively poor PG; (3) the sedimentary environments of the Xidashan-Xishanbulake and Moheershan formations in the Tadong low uplift are similar. They were deposited in warm and humid climatic conditions, in oxygen-deficient environments, with stable terrigenous inputs, high paleoproductivity, high paleosalinity, weak water-holding capacity, and no significant hydrothermal activity; and (4) the relationship between TOC and the paleoproductivity parameter (P/Ti) is most significant in the Lower Cambrian Xidashan-Xishanbulake Fm., whereas correlation with other indicators is not evident. This suggests a productivity-driven OM enrichment model, where input of land-derived material was relatively small during the Middle Cambrian, and the ancient water exhibi

关键词： Conventional resources hydrocarbon generation potential geochemistry sedimentary environment enrichment mechanism organic matter Cambrian Tadong low uplift SOUTH CHINA CONSTRAINTS SOURCE-ROCK EVALUATION TURPAN-HAMI BASIN GEOCHEMICAL CHARACTERISTICS BLACK SHALES RARE-EARTH NW CHINA LOWER ORDOVICIAN SILICEOUS ROCKS TRACE-ELEMENTS

The Influence of CO on the Carbon Isotopic Composition of CH_4 in Closed Pyrolysis Experiment With Coal

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Chinese Journal Of geochemistry 2004年第4期23卷 359-365页

作者：刘全有刘文汇 State key laboratory of {2. geochemistry Lanzhou Institute of Geology Chinese Academy of Sciences

A low-mature coal (R o=0.4%, from the Manjia’er depression, Tarim Basin, China) was subjected to closed system pyrolysis, in sealed gold tubes, under isothermal temperature conditions. The carbon isotopic compositions of the pyrolyst fractions (hydrocarbon, CO 2. CO, etc.) at two temperature points (350°C and 550°C) were measured. The results showed that δ 13C CH 4 value is generally heavier at 350°C than that at 550°C, because the high abundance of CO generated at low temperature would greatly influence δ 13C CH 4 value, and the retention time of CO in gas chromatograph is close to that of CH 4. But CO is formed through chemical reaction of the oxygen-containing functional group -C=O, e.g. lactones, ketones, ether, etc. at low temperature, while CO 2.comes mainly from decarboxylization. The carbon isotopic composition of coal gas from Lanzhou Coal gas Works was definitely different from that of thermally pyrolysed products from coal. The δ 13C CH 4 value of coal gas was abnormally heavier than δ 13C CO. At the same time, the reversed sequence ( δ 13C 1> δ 13C 2. of δ 13C 1 and δ 13C 2.happened. The bond energy of free ions generally decides the sequence of generation of hydrocarbon fractions according to the chemical structure, whereas the stability of pyrolysate fractions and their carbon isotope fractionation are affected by the C-C bond energy.

关键词：低级无烟煤铅热仿真试验煤气碳同位素地球化学

Typical end-member oil derived from Cambrian-Lower Ordovician source rocks in the Tarim Basin, NW China

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Petroleum Exploration and Development 2018年第6期45卷 1177-1188页

作者： BAO Jianping ZHU Cuishan WANG Zhifeng key laboratory of Oil & {2. Resource and Exploration Technology Geochemistry Department Yangtze University

Based on GC-MS data of saturate and aromatic hydrocarbon fractions in crude oils from Well TD 2.and the Yingmaili and Tazhong area in the Tarim Basin, the end-member oil derived from Cambrian-Lower Ordovician source rocks was determined. The analytical results show that the crude oil from Well TD2.is rich in 3-6 ring polycyclic aromatic hydrocarbons without alkyl group, suggesting that this oil was altered by an abnormally thermal event. It contains a complete series of normal alkanes and 2.-norhopanes,

关键词： biomarkers triaromatic steroids polycyclic aromatic hydrocarbons end-member oil Tarim Basin