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Summary. A number of settlements and other traces of occupation have been identified in the mountainous areas near to tin and copper deposits in the Erzgebirge, and some of them excavated. The newly collected evidence seems to suggest that many small sources of metals, both tin and copper, were exploited, the former metal by washing from the river and creek beds. Though these sources were more modest than the British and Spanish tin supply, they seem to have served the Bohemian and Saxon Bronze Age cultures well. 相似文献
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G.H. Packham I.G. Percival R.B. Rickards A.J. Wright 《Alcheringa: An Australasian Journal of Paleontology》2013,37(2):251-261
Precordilleran Late Palaeozoic brachiopod genera considered for this palaeobiogeographical analysis belong to four faunal associations: the low diversity Early Carboniferous (Tournaisian) Protocanites scalabrinii-Azurduya chavelensis Zone; the Late Carboniferous (Bashkirian-Moscovian) Levipustula fauna, which appears in sequences associated with glacial intervals; the latest Carboniferous-earliest Permian (Gzhelian-Asselian) Rhipidomella-Micraphelia and Tuberculatella-Aseptella associations, and the Early Permian (mid to late Asselian) Tivertonia jachalensis-Streptorhynchus inaequiornatus Biozone. The brachiopod affinities of the Precordillera are compared with the biogeographical Late Palaeozoic regions previously suggested by other authors using cluster analysis. During the Bashkirian-Moscovian, the Precordilleran faunas show a high affinity with the Austral Realm because of the presence of the Levipustula faunal elements in Eastern Australia. At the same time the affinity with the central and North American Regions is very low. The Early Permian Precordilleran faunas demonstrate highest affinity with the Gondwanan Realm with several genera also linked to the Tethyan and Boreal Realms. After the Late Carboniferous glacial episodes that affected the southwestern Gondwanan margin, the Precordilleran region underwent climatic amelioration. Subsequently, the Early Permian Precordilleran brachiopod assemblages are characterized by typical cool to cold water genera widely developed in the core Gondwanan Realm, with fewer genera (such as Kochiproductus, Rhynchopora and Neochonetes) suggesting a warmer water influence. The Precordilleran faunas demonstrate an increase in brachiopod diversity from the Carboniferous to the Permian, related to water temperature changes and to the palaeogeographical evolution of the southwestern Gondwanan margin and the movement of Gondwana across the South Pole. 相似文献
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R. KENT NEWMYER 《Journal of Supreme Court History》2006,31(2):126-140
American constitutional history in the early national period seems at times to be a conversation—or an argument—among Virginians. There's James Madison, George Washington, George Mason, John Taylor of Caroline County, Judge Spencer Roane, John Randolph of Roanoke, to mention only some. At the center of this constellation were John Marshall and Thomas Jefferson. 相似文献
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