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Previous issue date: 2014-02-21 / This work presents the results of the first imaging of continental slope adjacent to Potiguar Basin, in the equatorial Brazilian margin (NE Brazil). Swath bathymetry provided a complete coverage of seafloor between the upper and middle slope (100-1,300 m). Fifteen submarine canyons were mapped. The shape of the slope reflects in distinct spatial distribution of the canyons. The western area displays convex profiles which implied a greater amount of incisions by canyons. Some of them have gradient walls higher than 35?. They were classified according to location and morphology. The canyons with heads indenting shelf edge, association with a incised valley and a large fluvial system, high sinuosities, V shape, terraces along margins, further erosive features such as landslide and gullies allow to deduce a sandy-gravelly sedimentation. These canyons are associated with deposition of submarine fan systems that have been considered permeable hydrocarbon reservoirs. The presence of gullies, furrows and dunes demonstrates the role of bottom currents in the shaping of the slope. The enlargement of canyons and the change in the course when they cross the border fault imply that tectonic has also influenced in the morphology of deep waters environments of Potiguar Basin. The current sedimentation of continental slope is considered mixed because the sediments are composed of siliciclastics and bioclasts. Predominant siliciclastics are calcite, dolomite, quartz, and clay minerals. The presence of stable minerals (zircon, tourmaline and rutile), and fragmented bioclasts implies the contributions of Rivers A?u and Apodi / Esta disserta??o apresenta os resultados do primeiro imageamento realizado no talude continental, em ?rea adjacente ? Bacia Potiguar, na margem equatorial brasileira (NE Brasil). Dados de batimetria multifeixe forneceram uma cobertura completa do fundo oce?nico entre o talude superior e o talude intermedi?rio (100-1300 m). Quinze canyons submarinos foram mapeados. A forma do talude reflete na distinta distribui??o espacial dos canyons. A parte oeste apresenta perfis convexos o que implicou numa maior quantidade de incis?es pelos canyons. Alguns deles possuem paredes com declividades maiores que 35?. Os canyons foram classificados de acordo com sua localiza??o e morfologia. Os canyons com cabeceiras entalhadas na plataforma, conex?o com sistemas fluviais, altas sinuosidades, formas em V , terra?os ao longo das margens e com fei??es erosivas como ravinas permitem deduzir uma sedimenta??o areno-cascalhosa. Estes canyons s?o associados ? deposi??o de sistemas de leques submarinos que t?m sido considerados reservat?rios de hidrocarbonetos. A presen?a de ravinas, ranhuras e dunas demonstram o papel das correntes de fundo na forma do talude. Os alargamentos dos canyons e a mudan?a na dire??o do curso onde cruzam a falha de borda da bacia implicam que a tect?nica tamb?m influencia na morfologia dos ambientes profundos da Bacia Potiguar. A sedimenta??o atual do talude continental ? considerada mista, pois os sedimentos possuem componentes silicicl?sticos e biocl?sticos. Dentre os silicicl?sticos destacam-se calcita, dolomita, quartzo e os argilominerais. A presen?a de alguns minerais pesados tais como zirc?o, turmalina e rutilo, bem como biocl?sticos fragmentados, indicam a maturidade dos sedimentos e a contribui??o dos Rios A?u e Apodi para os sedimentos da ?rea de estudo
Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/18841 |
Date | 21 February 2014 |
Creators | Almeida, Narelle Maia de |
Contributors | CPF:31481981404, http://lattes.cnpq.br/3595069999049968, Bezerra, Francisco Hilario Rego, CPF:37923579415, http://lattes.cnpq.br/6050302316049061, Silva, Cleverson Guizan, CPF:60890223734, http://lattes.cnpq.br/2192755725741120, Vital, Helenice |
Publisher | Universidade Federal do Rio Grande do Norte, Programa de P?s-Gradua??o em Geodin?mica e Geof?sica, UFRN, BR, Geodin?mica; Geof?sica |
Source Sets | IBICT Brazilian ETDs |
Language | Portuguese |
Detected Language | English |
Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis |
Format | application/pdf |
Source | reponame:Repositório Institucional da UFRN, instname:Universidade Federal do Rio Grande do Norte, instacron:UFRN |
Rights | info:eu-repo/semantics/openAccess |
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