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This paper reports the first fossil (Tertiary) occurrence of freshwater sponges of the genus Ephydatia in the southern hemisphere. The sponges appear in diatomite lacustrine sediments of Late Miocene Quillagua Formation (Chile, Atacama region). The investigated specimens represent a new species, Ephydatia chileana sp. nov., which is close to the Recent cosmopolitan E. fluviatilis. On the basis of sedimentological and diatom assemblage data, sponge-bearing diatomites have been interpreted as deposited in open offshore shallow lacustrine conditions with slightly alkaline waters. The sponges show malformations, similar to some diatoms and probably caused by high heavy metal concentrations in a lake water. These concentrations are related to hydrothermal activity, which favored the leaching of volcanic rocks that outcrop extensively in the catchment.  相似文献   
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During the Mw=6.9 January 1, 1980 earthquake in the Azores, the damage distribution in the town of Angra do Heroísmo, in Terceira Island, had a non-homogeneous spatial character. In order to understand the observed pattern of damage a microtremor survey was carried out, using ambient vibrations, and the data were analysed with the J-Sesame software, following the H/V Nakamura methodology. The results are in good agreement with the surface geology and they show a good correlation with the observed damages. Two building surveys were performed, in 1980 on damage evaluation and in 2000 on characterization of few building parameters. With all these elements (surface geology type, soil peak frequency, building type, number of stories and damage level) for 2111 buildings it was possible to perform several interparameter analysis, which enabled the identification of indicators that could be used to improve the damage estimation for future events.  相似文献   
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