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| Deville, Eric; Mascle, A.; Callec, Y.; Huyghe, P.; Lallemant, S.; Lerat, O.; Mathieu, X.; De Carillo, C. Padron; Patriat, Martin; Pichot, Thibaud; Loubrieux, B.; Granjeon, D.. |
| Several marine geophysical data and piston-coring surveys acquired during the last decade allow one to better understand the close dynamic interactions between the sand-rich Orinoco turbidite system and the compressional structures of the Barbados prism. These interactions have been active since Eocene time as illustrated by the study of outcrops onshore Barbados Island. Because of strong morphologic and tectonic control in the east-Caribbean active margin, the present-day Orinoco turbiditic pattern system does not exhibit a classic fan geometry. The sea-floor geometry between the slope of the front of the Barbados prism and the slope of the South-American margin induces the convergence of the turbidite channels toward the abyssal plain, at the front of... |
| Tipo: Text |
Palavras-chave: Turbidite system; Active margin; Orinoco; Barbados. |
| Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00252/36373/34913.pdf |
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| Chen, Ju-chin; Lo, C. Y.; Lee, Y.t.; Huang, S. W.; Chou, P. C.; Yu, H. S.; Yang, T.f.; Wang, Y. S.; Chung, S. H.. |
| The cored sediments sampled by R/V Marion Dufrense are mostly muds consisting mainly of quartz, feldspar, illite, chlorite + kaolinite and calcite. Authigenic carbonates mainly composed of aragonite, calcite, dolomite and associated with Fe-montmorillonite and pyrite occur in core samples collected from station MD-052911 (22 degrees 15.6' N, 119 degrees 51.0' E) at 2137-2140 cm and 2237-2240 cm depth which may be formed via sulfate reduction by CH4. In general Illite/Quartz intensity ratios of the sediments show little variation with core depth indicating the relatively constant abundance of illite in the source rock on Taiwan. The cored sediments have higher average Al2O3, Sigma FeO and MgO but lower SiO2, Na2O, and CaO contents when compared with upper... |
| Tipo: Text |
Palavras-chave: Cored sediments; Mineralogy and chemistry; Active margin; Off SW Taiwan. |
| Ano: 2007 |
URL: https://archimer.ifremer.fr/doc/00235/34618/32942.pdf |
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| Villar-muñoz, Lucía; Vargas-cordero, Iván; Bento, Joaquim; Tinivella, Umberta; Fernandoy, Francisco; Giustiniani, Michela; Behrmann, Jan; Calderón-díaz, Sergio. |
| Large amounts of gas hydrate are present in marine sediments offshore Taitao Peninsula, near the Chile Triple Junction. Here, marine sediments on the forearc contain carbon that is converted to methane in a regime of very high heat flow and intense rock deformation above the downgoing oceanic spreading ridge separating the Nazca and Antarctic plates. This regime enables vigorous fluid migration. Here, we present an analysis of the spatial distribution, concentration, estimate of gas-phases (gas hydrate and free gas) and geothermal gradients in the accretionary prism, and forearc sediments offshore Taitao (45.5°–47° S). Velocity analysis of Seismic Profile RC2901-751 indicates gas hydrate concentration values <10% of the total rock volume and extremely... |
| Tipo: Text |
Palavras-chave: BSR; Gas hydrate; Methane; Seepage; Active margin; Chile Triple Junction. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00475/58678/61173.pdf |
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