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2023年6月17—18日,首届“人类世科学大会”在古都西安成功举办,本次会议由中国地质学会主办,中国地质学会人类世研究分会、中国科学院地球环境研究所、黄土科学全国重点实验室(筹)、陕西省基础学科(地球系统科学)研究中心共同承办。 相似文献
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Timothy M Kusky 《中国地质大学学报(英文版)》2011,(2)
The geometry and timing of amalgamation of the North China craton(NCC) have been controversial,with three main models with significantly different interpretations of regional structure,geochronology,and geological relationships.The model of Zhao G C et al.suggests that the eastern and western blocks of the NCC formed separately in the Archean,and an active margin was developed on the eastern block between 2.5 and 1.85 Ga,when the two blocks collided above an east dipping subduc-tion zone.The model of Kusky ... 相似文献
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Samples were continuously collected from aerosol, fresh snow, and snow pits on Glacier No. 1 at Urumqi River source in eastern Tianshan (天山) Mountains. The deposition processes and the characteristics of mineral dust microparticles from aerosol to fresh snow, and then evolution to the snow pit were determined. Total dust microparticle concentration in the surface snow and aerosol showed a similar temporal variation trend, which was strongly associated with regional and local at-mospheric circulation in the ... 相似文献
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The Huimin (惠民) depression is a third-level tectonic element of the Bohai (渤海) Bay basin in eastern China. The central uplift belt is the most important oil and gas accumulation zone in the depression, but the lack of adequate geological studies in the area has greatly hindered exploration and development. In this article, using seismic data, fracture mechanics, and a combination of data on fault growth indices and fault throws, we present an analysis of tectonic activity in the central uplift belt and adja... 相似文献
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High quality marine source rock (HQMSR) is the key prerequisite for medium to large hydrocarbon accumulations. However, the forming mechanism remains unclear. On the basis of the in-vestigation for the geodynamic setting of the Middle-Upper Yangtze during the Early Cambrian in dif-ferent spatial scales and the analysis of trace elements, the main controlling factors of the development of high quality marine source rock are discussed, with specific consideration of the burial rate of the organic matter. The ... 相似文献
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Mixed carbonate-siliciclastic sedimentation is common in the Upper Permian-Lower Tri-assic in the western Sichuan(四川) basin.The extensional movement was strong in the Late Permian,resulting in differential uplifting of fault blocks.During this period,there was an extensive retrogres-sion.The Kangdian(康滇) ancient land progressive uplifted and enlarged,forming the major prove-nance of terrigenous clastics.In Changxingian age,mixed terrigenous-carbonate sedimentation was dis-tributed in the area between Dafeis... 相似文献
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A 1.2 m snow pit was recovered on July 29th, 2009 from the Bogda Glacier, eastern Tianshan (天山). The sample site temperature of -9.6 ℃ indicates that the unique glaciochemical re-cord was well preserved and suitable for the reconstruction of air pollution levels in this previously un-explored region. Samples were analyzed for major ions (Na+, K+, Ca2+, Mg2+, NH4+, Cl-, SO42-, NO3-, HCOO-, and CH3COO-). NO3- and SO42- were characterized by significant high levels of pollution con-centration. Most air masses ... 相似文献