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101.
HE Yue GE Wenchun HE Zhonghu YANG Hao DONG Yu JI Zheng ZHAO Di JING Yan 《《地质学报》英文版》2019,93(Z2):23-24
Mesozoic ophiolites crop out discontinuously in the Indo‐Myanmar Ranges in NE India and Myanmar, and represent the remnants of the Neotethyan oceanic lithosphere. These ophiolites in the Indo‐Myanmar Ranges are the southern continuation of the Neotethyan ophiolites occurring along the Yarlung Zangbo Suture Zone in southern Tibet farther northwes, as indicated by their coeval crystallization ages and geochemical compositions. The Kalaymyo ophiolite is located in the central part of the Indo‐Myanmar Ranges (Myanmar). The Kalaymyo ophiolite are composed of olivine (Fo = 89.8–90.5), orthopyroxene (En86‐91Wo1‐4Fs8‐10; Mg#=89.6–91.9), clinopyroxene (En46‐49Wo47‐50Fs3‐5; Mg# = 90.9–93.6) and spinel (Mg# = 67.1–78.9; Cr# = 13.5–31.5), and have relatively homogeneous whole‐rock compositions with Mg# of 90.1–90.8 and SiO2 (41.5–43.65 wt.%), Al2O3 (1.66–2.66 wt.%) and CaO (1.45–2.67 wt.%) contents. They display Light Rare Earth Element (LREE)‐depleted chondrite‐normalized REE patterns and show a slight enrichment from Pr to La. The Kalaymyo peridotites are characterized by Pd‐enriched chondrite‐normalized PGE patterns with superchondritic (Pd/Ir)CN ratios (1.15–2.36). Their calculated oxygen fugacities range between QFM–0.57 and QFM+0.90. These features collectively suggest that the Kalaymyo peridotites represent residual upper mantle rocks after low to moderate degrees (5–15%) of partial melting at a mid‐ocean‐ridge environment. The observed enrichment in LREE and Pd was a result of their reactions with enriched MORB‐like melts, percolating through these already depleted, residual peridotites. The Kalaymyo and other ophiolites in the Indo‐Myanmar Ranges hence represent mid‐ocean ridge–type Tethyan oceanic lithosphere derived from a downgoing plate and accreted into a westward migrating subduction–accretion system along the eastern margin of India. 相似文献
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淋溶是有害微量元素从煤或煤矸石中析出后污染环境的重要途径。本文在对河南新密-荥巩矿区煤矸石淋溶实验的基础上,研究了有害微量元素从煤矸石中淋溶析出的浓度及淋溶过程中pH值的变化规律,探讨了不同淋溶实验方法对有害微量元素溶出的影响,并对有害微量元素溶出的环境意义进行了讨论。 相似文献
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Coal-bearing strata are widespread in the western Great Khingan Mountains. Abundant coal resources have been found in the Jurassic Alatanheli Groups, the Cretaceous Bayanhua Groups, the Damoguaihe Formation and the Yimin Formation. The organic geochemical characteristics were analyzed in combination with hydrocarbon source rock evaluation and molecular organic geochemistry experiments, and the coal gas potential of coal seams was evaluated. The source rock evaluation results indicated that the Mesozoic coal samples have the characteristics of high organic matter abundance(TOC>30%), low maturity(Ro values of approximately 0.6%), and type Ⅲ composition. The hydrocarbon generation potentials of the Alatanheli Groups and Bayanhua Groups are high, while the generation potentials of the Damoguaihe Formation and the Yimin Formation are low. The results of geochemistry show that the depositional environment of the coal seam was a lacustrine, oxidizing environment with a low salinity, and the source of the organic matter was mainly higher plants. Affected by weak degradation, the coal seams mainly formed low-maturity gas of thermal catalytic origin. The Cretaceous coal seams contain a large amount of phytoplankton groups deposited in a low-stability environment affected by a transgression event, and the potential range varied widely. For the Jurassic coal seams, the depositional environment was more stable, and the coal seams feature a higher coal-forming gas potential. 相似文献
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Peiyuan HU Qingguo ZHAI Guochun ZHAO Peter A.CAWOOD Yue TANG Yiming LIU 《中国科学:地球科学(英文版)》2024,(4):899-918
The composition and geological evolution of pre-Cryogenian material in the Tibetan Plateau and its surrounding areas have played an important role in studying the formation and evolution of early supercontinents on Earth. This paper systematically summarizes the characteristics of pre-Cryogenian sedimentation, paleontology, magmatism, and metamorphism in the Tibetan Plateau and its surrounding areas. Based on existing data, the records of pre-Cryogenian sedimentation and paleontology are mainly ... 相似文献
109.
A New Ichnogenus Kailidiscus Produced by Attachment from the Middle Cambrian Kaili Formation in Taijiang, Guizhou Province, China 总被引:1,自引:0,他引:1
WANG Yue 《《地质学报》英文版》2006,80(1):27-37
Over 190 specimens of an attachment ichnofossil Kailidiscus (n. ichnogen.) have been found in the Kaili Bitoa, a Burgess Shale-type biota, from the middle Kaili Formation (early Middle Cambrian) in Taijiang County, Guizhou Province, southern China. Kailidiscus is an epichnia with a circular to oval attachment platform, on which there is a carbonaceous film probably formed by the body of the living organism. Structures such as a marginal furrow, an inner and outer marginal ride, many convex fold-ridges, and a large caved peripheral furrow on the attachment platform may be the result of basal tissues of a sessile organism that wrinkled to increase the attachment's surface area. The Kailidiscus organism may have been a sessile cnidarian attached to the muddy seafioor. Kailidiscus organisms lived in relatively quiet water, and were buried by a sudden influx of sediment. 相似文献
110.
Jiang Xianghu Wang Yue Han Yanyan Xue Yan Yang Wen Zang Yang Deng Shiguang Ma Yawei Yao Qi Song Jin Shi Haixi Zhang Xiaotao Meng Lingyuan Zhou Longquan 《中国地震研究》2018,32(1):141-149
正1 SURVEY OF GLOBAL SEISMICITY A total of 8 strong earthquakes with M_S≥7.0 occurred in 2017(from January 1 to December31,2017)throughout the world,according to the China Seismic Network,including one with M_S≥8.0,i.e.,the great earthquake with M_S8.2 which occurred on September 8,2017 in 相似文献