An?lise dos microssismos registrados no arquip?lago de S?o Pedro e S?o Paulo (ASPSP) e suas rela??es com vari?veis oceanogr?ficas

• Main Author: Queiroz, Daniel ?vora de
• Other Authors: 90376285400
• Language: Portuguese
• Published: Universidade Federal do Rio Grande do Norte 2016
• Subjects: CNPQ::CIENCIAS EXATAS E DA TERRA::GEOCIENCIAS::GEOFISICA; Microssismos; Ondas oce?nicas de gravidade; Arquip?lago de S?o Pedro e S?o Paulo; Clima de ondas; Oceano Atl?ntico
• Online Access: http://repositorio.ufrn.br/handle/123456789/19604

Submitted by Automa??o e Estat?stica ([e-mail]) on 2016-01-14T19:08:15Z No. of bitstreams: 1 DanielEvoraDeQueiroz_DISSERT.pdf: 1637643 bytes, checksum: 5f07f026aca2b21db16fe4bc9812146a (MD5) === Approved for entry into archive by Arlan Eloi Leite Silva ([e-mail]) on 2016-01-15T21:13:03Z (GMT) No. of bitstreams: 1 DanielEvoraDeQueiroz_DISSERT.pdf: 1637643 bytes, checksum: 5f07f026aca2b21db16fe4bc9812146a (MD5) === Made available in DSpace on 2016-01-15T21:13:03Z (GMT). No. of bitstreams: 1 DanielEvoraDeQueiroz_DISSERT.pdf: 1637643 bytes, checksum: 5f07f026aca2b21db16fe4bc9812146a (MD5) Previous issue date: 2014-06-27 === Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES === Microssismos s?o vibra??es cont?nuas na Terra registradas na faixa de frequ?ncia de mili Hertz para 1 Hz. Estas vibra??es s?o em sua maioria compostas de ondas Rayleigh e s?o mais fortes na faixa de frequ?ncia de 0.04 ? 1 Hz. Seus mecanismos de gera??es ainda s?o quest?es de debates, mas ? consenso que eles est?o relacionados com perturba??es atmosf?ricas e ondas oce?nicas de gravidade. O Arquip?lago de S?o Pedro e S?o Paulo (ASPSP) est? localizado na regi?o equatorial do Oceano Atl?ntico cerca de 1.100 km de dist?ncia da costa do nordeste brasileiro. O ASPSP ? composto por um conjunto de v?rias pequenas forma??es rochosas com uma ?rea total de aproximadamente 17.000 m?. Devido a sua localiza??o distante do continente, isolamento e aus?ncia de ru?dos provocados pela atividade humana, este local ? ideal para a medi??o de ru?do micross?smico e investiga??o de sua rela??o com algumas vari?veis clim?ticas e oceanogr?ficas. No ASPSP registramos microssismos prim?rios (PM) entre 0.04 - 0.12 Hz e microssismos secund?rios (SM) entre 0.12 - 0.4 Hz durante 10 meses em 2012 e 2013. As an?lises indicam uma boa correla??o entre o ru?do micross?smico na regi?o e uma depend?ncia do clima de ondas. Em particular, com inverno no hemisf?rio norte. Tamb?m ? mostrado que a maior parte do PM ? gerado no pr?prio ASPSP. O local de gera??o do SM depende do comportamento das vari?veis clim?ticas e oceanogr?ficas no hemisf?rio norte. === Microseisms are continuous vibrations pervasively recorded in the mili Hertz to 1 Hz frequency range. These vibrations are mostly composed of Rayleigh waves and are strongest in the 0.04 to 1 Hz frequency band. Their precise source mechanisms are still a matter of debate but it is agreed that they are related to atmospheric perturbations and ocean gravity waves. The Saint Peter Saint Paul Archipelago (SPSPA) is located in the equatorial region of the Atlantic Ocean about 1,100 km distant from the Brazilian northeastern coast. The SPSPA is composed by a set of several small rocky formations with a total area of approximately 17,000 m?. Due to its remote distance from the continent and the lack of cultural noise, this location is a unique location for measuring microseismic noise and to investigate its relation with some climate and oceanographic variables. In the SPSPA we have recorded both primary microseisms (PM) at 0.04 ? 0.12 Hz and the secondary microseisms (SM) at 0.12 ? 0.4 Hz during 10 months in 2012 and 2013. Our analysis indicates a good correlation between the microseismic noise in the region and a seasonal dependency. In particular, the winter in the northern hemisphere. We have also shown that most of the PM is generated in the SPSPA itself. The SM source location depends with the seasonal climatic and oceanographic variables in the northern hemisphere