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181.
M.R. Walter I.N. Krylov W.V. Preiss 《Alcheringa: An Australasian Journal of Paleontology》2013,37(4):287-305
New forms of late Precambrian stromatolites are described from the Amadeus and Georgian Basins and additional information is given on Minjaria pontifera Walter from the Bitter Springs Formation. Tesca stewartii gr. et f. nov. is described from the Boord Formation, Elleria minuta gr. et f. nov. from the Pioneer Sandstone, and Tungussia julia f. nov. from the Julie Formation. The latter is compared with Tungussia cf. T. julia from the Wonoka Formation, South Australia. Acaciella australica Walter has been recognised in the Yackah Beds of the Georgina Basin, supporting a correlation with the Bitter Springs Formation. The stromatolites described were selected because of their potential regional and global stratigraphic significance. 相似文献
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Donata Magrini Donato Attanasio Susanna Bracci Emma Cantisani Walter Prochaska 《Archaeological and Anthropological Sciences》2018,10(5):1141-1152
An efficient and non-destructive method to classify white marble artifacts by using a hand-held, portable XRF analyzer (pXRF) is here reported. The identification is based on the uniquely high strontium content of this marble and has been verified by testing 32 artifacts, most of which had already been provenanced, using conventional micro-destructive analyses. Besides strontium, other potential provenance indicators, such as manganese and iron, were analyzed and their concentration values obtained after empirical calibration of the instrument by using 17 quarry samples of known composition. The results show that Göktepe/non-Göktepe discrimination is almost always possible (30 artifacts) and that additional analyses are required only when the Sr value is at the lower edge of the Göktepe field (2 artifacts). The success of the method, however, resides in the particular composition relative to trace elements of Göktepe and is not easily extended to other marble varieties. Main reasons are related to insufficient accuracy at low concentration values, intrinsic trace variability of marble artifacts, surface effects that may produce not representative results. Interest in the method therefore is tightly linked to the exceptional importance of Göktepe as a sculptural marble, in which case, detailed data, obtained with a fast and totally non-destructive method, may provide relevant information concerning chronology, workshops, and places of production of the artifacts. 相似文献
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正Intertwined Institutions:Slavery as an Example While Global History and Entangled History are nowadays very much focused on modern times,there is a central area in which ancient history has set the pace for research since the 18th century:slavery.Slavery was common in many parts of the world up to the 19th century,it connected regions that were far apart,and it had drastic repercussions on both the"delivering"and the"receiving"areas.The 相似文献
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Walter N. Niven 《Scottish Geographical Journal》2013,129(1):24-29
An attempt is made to identify the main trends in the development of physical geography as a distinctive discipline. In particular the relationship between physical and human geography is examined with a view to identifying possible paths for the future development of physical geography as an integrated discipline. 相似文献
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