989 resultados para 135-835B


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Concentrations of dark-colored, highly vesicular, quench-textured mesostasis occur commonly in volcanic rocks drilled in the Lau Basin during Leg 135. These segregations occur as veins, patches, and vesicle linings in rocks with 49%-54% SiO2. The segregations are depleted in Mg, Ca, Al, Sc, Ni, and Cr and enriched in Ti, Ba, Y, and Zr compared to the groundmass with which they occur. Many of the segregations are unusually enriched in copper. The elemental variations show that the segregations are residual liquids produced by 12%-55% crystallization of plagioclase and clinopyroxene, with minor olivine, opaques, or orthopyroxene from the groundmass melt. The liquids forming the segregations are mobilized and emplaced in earlier formed vesicles during the rapid crystallization of the groundmass. The dominant process in this mobilization and emplacement is volatile exsolution from crystallizing melts constrained by a rigid crystalline framework. This exsolution produces significant overpressures within the late-stage melts; the overpressure drives the residual melts through the walls of the older vesicles, along planes of weakness, and into voids. This mechanism is consistent with the occurrence of bimodal vesicle populations in many of the host lavas.

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This book offers a framework for the influence of context on evaluation practice and is applied to three case studies: environmental context; indigenous context and political context; and finishes with a process for implementation.

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Contenido: El orden divino del hombre / Octavio N. Derisi – El fundamento de la metafísica tomista : el Esse e Intelligere divino, fundamento y causa de todos ser y entender participados / Octavio N. Derisi – Lógica y realidad / Gustavo E. Ponferrada – La lógica actual y la existencia de Dios / Adalberto F. Villecco – Versión subjetivista y realista de los llamados derechos subjetivos de la personalidad o esenciales del hombre / Rodolfo Luis Vigo (H.) – Notas y comentarios -- Bibliografía

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To be able to carry out physical, chemical and biological investigations on a lake, one needs a thorough knowledge of the volume of water and the shape of the lake basin. Little is known about the about the morphology of the lakes in Schleswig-Holstein and its ecological consequences. For this research a 30 KHz echo sounder with sediment transceiver was used to carry out profile determinations (echo soundings). This apparatus continuously records on paper the different reflexions and absorptions of the sediment and water body in the corresponding depth. By this, acoustically noticeable layers and different densities in the sediment and 'scattering layers' in the water body due to physical, chemical and biological reasons (e.g. plans and single fish) are made visible. Result are summarised here regarding the echo soundings in Blunker See.