Utilizac¸ ˜ao de m´etodos geof´isicos para mapeamento de lama fluida

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Revista Brasileira de Geof´sica (2011) 29(3): 487-496 ı © 2011 Sociedade Brasileira de Geof´sica ı ISSN 0102-261X www.scielo.br/rbg ´
UTILIZACAO DE METODOS GEOF´SICOS PARA MAPEAMENTO DE LAMA FLUIDA
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NO PORTO DE TUBARAO, VITORIA (ES-BRASIL) a Val´ria da S. Quaresma1 , Alex C. Bastos1 , Diego V. Loureiro1,2 e Sandro Paix˜o2 e Recebido em 15 fevereiro, 2011 / Aceito em 2 agosto, 2011
Received on February 15, 2011 / Accepted on August 2, 2011

ABSTRACT. Fluid mud are frequently observed in navigational channels and their characterization and mapping are very important for safety reasons. This study investigates the response of different acoustic equipments on the identification and mapping of fluid mud. Sonographic, bathymetric and sub-bottom profile surveys were carried out in order to acoustically map the seabed. Short sediment cores were collected to determine the seabed bulk density. The survey was undertaken along
Porto de Tubar˜o (Esp´rito Santo State) as part of a dredging project. The occurrence of fluid mud was confirmed by the indirect acoustic methods and direct sediment a ı bulk density data. Acoustic signals behave differently in the presence of fluid mud in all frequency cases, which correlates with sediment bulk densities. The method applied herein proved to be efficient and applicable for these areas.
Keywords: fluid mud, high resolution geophysics, dual frequency bathymetry.
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e o ¸˜ a ¸˜ o RESUMO. A ocorrˆncia de dep´ sitos de lama fluida e muito comum em canais de navegacao e, por esta raz˜o o mapeamento e a caracterizacao destes dep´ sitos se
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tornam cada vez mais importantes para a manutencao da navegabilidade destas areas. Dessa forma, o objetivo deste trabalho foi de demonstrar a aplicac ao de m´todos
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¸˜ e ac´ sticos de investigacao geof´sica na identificacao da ocorrˆncia de lamas fluidas e seu mapeamento. Para tanto, foram realizados levantamentos s´smicos, batim´tricos, u ¸˜ ı ¸˜ e ı e ´