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71.
Petrographic features, C, O, S, and Sr isotopes were determined, and fluid inclusions (FI) were analyzed on various stages of vug‐ and fracture‐fillings from the Cambrian and Lower Ordovician reservoirs in the Tazhong area, Tarim basin, NW China. The aim was to assess the origin of pyrite and anhydrite and the processes affecting sulfur during diagenesis of the carbonates. Pyrite from seven wells has δ34S values from ?22‰ to +31‰. The pyrites with low δ34S values from ?21.8‰ to ?12.3‰ were found close to fracture‐filling calcites with vapor‐liquid double‐phase aqueous fluid inclusions homogenization temperatures (FI‐Th) from 55.7 to 73.2°C, salinities from 1.4wt% to 6.59wt% NaCl equiv and δ13C values from ?2.3‰ to ?14.2‰, indicating an origin from bacterial sulfate reduction by organic matter. Other sulfides with heavier δ34S values may have formed by thermochemical sulfate reduction (TSR) during two episodes. The earlier TSR in the Middle and Lower Cambrian resulted in pyrites and H2S having δ34S values from 30 to 33‰, close to those of bedded anhydrite and oilfield water (approximately 34‰). The later TSR is represented by calcites with δ13C values as light as ?17.7‰ and FI‐Th of about 120–145°C, and pyrite and H2S with δ34S values close to those of the Upper Cambrian burial‐diagenetic anhydrite (between +14.8‰ and +22.6‰). The values of the anhydrite are significantly lighter than contemporary seawater sulfates. This together with 87Sr/86Sr values of anhydrite and TSR calcites from 0.7091 to 0.7125 suggests a source from the underlying Ediacaran seawater sulfate and detrital Sr contribution. 相似文献
72.
本文利用金相显微镜和扫描电镜能谱仪对郑韩故城热电厂墓地出土的l5件青铜器进行了分析,发现15件铜器的材质为铅锡青铜、锡青铜;制作工艺为铸造和热锻。热电厂墓地为东周时期郑韩故城贵族墓地,青铜器的初步分析研究为研究郑韩故城冶铸技术状况提供了参考资料。 相似文献
73.
Qiyao Liang Quanjia Chen Naifan Zhang Wei Zhang Chao Ning Dawei Cai 《International Journal of Osteoarchaeology》2023,33(2):271-284
The Nenjiang River Basin, located in the northern part of Northeast China, is an important cultural region that has attracted much attention from academic communities. Previous studies demonstrated that hunting and gathering always dominate the subsistence for prehistoric populations in this region. Herein, we further investigate the evolution of dietary and economic strategies in the Late Neolithic and Bronze Age occupations at the recently excavated Honghe site of the Nenjiang River Basin by means of a multidisciplinary approach incorporating zooarchaeological and stable isotope analysis. The results of zooarchaeological approaches indicate that the Honghe populations rely extensively on hunting and fishing during the Late Neolithic (4500–4000 cal BP), consistent with the results of previous studies. Interestingly, by the Bronze Age (3100–2400 cal BP), animal husbandry develops as one main economic strategy, corresponding to the probable decline of hunting and fishing, which is different from the previous reports. In addition, based on the results of stable isotopic approaches, C3 plants are always prominent diets for animals and humans from the Late Neolithic to the Bronze Age, which signifies that crop agriculture does not appear to have been of primary importance during either of these eras, in contrast to the C4 agricultural tradition formed in the Neolithic Age of the southern part of Northeast China. The findings of this paper shed some more light on the evolution of human subsistence strategies in the Nenjiang River Basin. 相似文献
74.
1938年底,正当中国抗战进入相持阶段时,国民党第二号人物汪精卫走上了叛国投敌的道路。一度扮演过英姿风发、慷慨悲歌的民主主义革命斗士的汪精卫何以最终堕落为遗臭万年的汉奸?汪氏叛国投敌的心理动机何在?本文拟就此作一探究。 相似文献
75.
蔡宗宪 《中国历史地理论丛》2009,24(1)
客馆为传统中国外交上的重要机构,由地主国设立,以接待归附者、使节、人质、入朝藩王、沙门与留学生等各种不同身分的外国人,试图落实招抚荒远、万国宾服的理想。南北朝时,客馆在数量与规制上有明显的发展,它除了解决外国人的食宿需求,也是重要的外交折冲场所。南北朝的客馆乃是拥有许多馆舍,颇具规模的馆区。客馆的方位受到城市格局变化的影响,南北朝以后,多位于城南。其地理位置也从城郭外向宫城靠近,且通常位于南北中轴线的通衢上。 相似文献
76.
77.
Fan Zhang;Yan Liu;Chao Ning;Jiashuo Zhang;Pengcheng Ma;Ruojing Zhang;Zerong Yun;Chen Duan;Dawei Cai;Haibing Yuan; 《International Journal of Osteoarchaeology》2024,34(1):e3274
The analysis of familial relationships among individuals co-buried in a shared tomb is crucial for understanding burial practices and the underlying social organization of ancient human society. However, archaeological interpretation of these relationships has traditionally relied on conjecture and circumstantial evidence. The development of next-generation sequencing technologies makes it possible to obtain genomic data from ancient individuals and thus can further estimate the genetic relatedness among these individuals in an accurate manner. In this study, we obtained the genomes of four individuals excavated from a single tomb in northern China. We found that three out of the four individuals were from a nuclear family, including the parents and their son, while the remaining female individual was genetically unrelated to the others. Our study not only shows that the burial custom was organized based on both biological relatedness and social kinship ties but also suggests the presence of likely female exogamy in ancient China. Finally, we find the genetic profile of these individuals carried a majority ancestry from the sedentary agriculturalists from the Central Plains of China and subtle ancestry that derived a gene pool associated with nomadic pastoralism, implying a long-standing genetic continuity among ancient populations in northern China, but with genetic and cultural connections with nomadic groups during the 11th to 13th centuries. 相似文献
78.
四世班禅精通佛学和传统文化知识,他担任扎什伦布寺住持,使该寺成为班禅活佛系统执掌的主寺;同时,他对四世达赖倾囊相授,担任拉萨祈愿大法会首座,维修大昭寺和甘丹寺灵塔殿金顶,成为格鲁派的领袖人物。此外,他还是五世达赖的上师,协助五世达赖的政教事业,并首倡与关外的清政权建立联系,参与觉囊派改宗等事。四世班禅为格鲁派的发展做出了重大贡献,由此确立了班禅活佛系统在格鲁派中的崇高地位。 相似文献
79.
Spatial and temporal variety of prehistoric human settlement and its influencing factors in the upper Yellow River valley,Qinghai Province,China 总被引：4，自引：0，他引：4
Guanghui Dong Xin Jia Robert Elston Fahu Chen Shuicheng Li Lin Wang Linhai Cai Chengbang An 《Journal of archaeological science》2013
We report an investigation of forty-two prehistoric sites in the upper Yellow River valley located in Guide, Jianzha, Hualong, Xunha and Minhe, Qinghai Province, China, including forty-four new radiocarbon dates from twenty-four sites, review published archaeological surveys and radiocarbon dates, analyze landform features and discuss the reasons for spatial and temporal variety of regional prehistoric human settlement. Our results suggest that people occupied the upper Yellow River valley during the early Holocene, but a continuous archaeological record begins only after about 5500 Cal yr BP. Thereafter, the intensity of prehistoric human settlement in the area is varied. Neolithic human settlement spread northwestward to high altitude areas of the upper Yellow River valley during early-mid Majiayao and Qijia periods, but moved southeastward to lower locations in the area during late Majiayao period. During the Bronze period, two coeval archaeological cultures, the Kayue and Xindian, occupied the upper Yellow River Region. Kayue archaeological sites are numerous and widely distributed in the high areas of the upper Yellow River, while Xindian sites are restricted to the lowest basin of the region. Variation in site density and location are likely the result of changing paleoclimate and technology. 相似文献
80.
绿色农业视角下青海特色农业发展路径及对策 总被引：4，自引：0，他引：4
绿色农业是二十一世纪农业发展的理想模式。青海独特的地域环境和资源条件形成了丰富的特色农业资源,也为发展绿色农业奠定了基础。文章通过对青海特色农业绿色化发展条件的分析,指出了特色农业的发展目标,并提出了实施路径及相关对策。 相似文献