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201.
Peng, J., Li, J., Slater, S.M., Li, W., Zhu, H. & Vajda, V. October 2017. Triassic palynostratigraphy and palynofloral provinces: evidence from southern Xizang (Tibet), China. Alcheringa 42, 67–86. ISSN 0311-5518.

Palynological analysis was carried out on Middle to Upper Triassic strata from Tulong, Nyalam County, southern Xizang (Tibet), China. Well-preserved miospore (pollen and spore) assemblages and sparse acritarch occurrences were identified. We recognized four formal and one informal biozones based on stratigraphically important taxa and compositional changes through the succession, in ascending order: the Triplexisporites Interval Zone (Anisian), the Staurosaccites quadrifidus Taxon-range Zone (upper Anisian to lower Norian), the Striatella Interval Zone (lower Norian), the Craterisporites rotundus Taxon-range Zone (middle to upper Norian) and the informal ‘Dictyophyllidites harrisii zone’ (Rhaetian). The zonation was supported by marine fossils (e.g., ammonoids and conodonts), and compositional similarity between the zones was examined using non-metric multidimensional scaling (NMDS). Correlation with other representative palynological sequences across Gondwana was also conducted. The presence of miospore taxa not previously recovered from the Late Triassic North and South China palynofloral provinces (e.g., Ashmoripollis reducta, Craterisporites rotundus, Enzonalasporites vigens, Minutosaccus crenulatus, Samaropollenites speciosus and Staurosaccites quadrifidus) calls for a new province in southwestern China, i.e., the Southern Xizang Province. It is proposed here that the modern expression of the northern boundary runs along the Yarlung Zangbo Suture, the remnant of the Tethys that separated the Indian Plate (southern Xizang) and the Lhasa Block during the Late Triassic. This new palynofloral province comprises typical elements of the Onslow Microflora, indicating the need for an extension of this microflora in southern Xizang, China.

Jungang Peng [], Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China, University of Chinese Academy of Sciences, Beijing 100049, China, Department of Palaeobiology, Swedish Museum of Natural History, Stockholm 104 05, Sweden; Jianguo Li* [], Key Laboratory of Economic Stratigraphy and Palaeogeography, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China; Wenben Li [], Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China; Sam M. Slater [], Vivi Vajda [], Department of Palaeobiology, Swedish Museum of Natural History, Stockholm 104 05, Sweden; Huaicheng Zhu [], State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China.  相似文献   

202.
Focused on the Hunan and Hubei areas during the Ming and Qing dynasties, this paper provides a discussion on the relief services for the aged. With an emphasis on the quota and object of the aged who needs to be relieved, the constructional scale of the relief houses and the operation patterns of the institutions, it reveals the gap between the ideal and the reality, the policies and the implementation, the philosophy of the philanthropy and the limit of the government budget. __________ Translated from Wuhan University Journal (Humanity and Social Science Edition), 2004: 3  相似文献   
203.
利用便携式能量色散型X射线荧光光谱仪和三维数字显微系统,对湖南出土的11颗战国时期典型的蜻蜓眼玻璃珠进行科学分析。基于获取的蜻蜓眼珠化学成分、表面和断面显微形貌等相关信息,确定了这批蜻蜓眼玻璃珠的成分体系、制作工艺和产地来源。研究结果表明:3颗蜻蜓眼玻璃珠属于泡碱型钠钙玻璃,1颗扁平蜻蜓眼玻璃珠为植物灰钠钙玻璃,均可能产自埃及或东地中海地区;3颗蜻蜓眼玻璃珠属于铅钡玻璃,还有4颗为钾钙玻璃,皆为战国时期典型的中国本土玻璃,应为楚国本地制作。这11颗蜻蜓眼玻璃珠均采用层叠镶嵌工艺,先制作珠体,然后再用不同玻璃条或片在未完全凝固的状态下进行镶嵌而成。  相似文献   
204.
出土于湖南衡阳何家皂北宋墓的纺织品上观察发现有灰蓝色固体物质附着,为查明其性质,采用扫描电镜-能谱法、激光拉曼光谱法和X射线衍射法结合能量色散X射线荧光光谱法和光学形貌观察等手段进行科学分析。结果表明,该物质为磷酸亚铁矿物——蓝铁矿[Vivianite:Fe_(3)(PO_(4))_(2)·8H_(2)O],其多形成于富铁、富磷、有机物含量较高且贫硫的缺氧还原沉积环境中,微生物活动亦对其生成有影响。该矿物的发现对墓葬环境特征与保存状态的研究有指示意义,在考古遗存中或可作为判断特殊埋藏条件的标志自生矿物之一。  相似文献   
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