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Carson, Brooke E.; Francis, Jason M.; Leckie, R. Mark; Droxler, Andre W.; Dickens, Gerald R.; Jorry, Stephan J.; Bentley, Sam J.; Peterson, Larry C.; Opdyke, Bradley N.. |
Ashmore Trough in the western Gulf of Papua (GoP) represents an outstanding modern example of a tropical mixed siliciclastic-carbonate depositional system where significant masses of both river-borne silicates and bank-derived neritic carbonates accumulate. In this study, we examine how benthic foraminiferal populations within Ashmore Trough vary in response to sea level-driven paleoenvironmental changes, particularly organic matter and sediment supply. Two 11.3-m-long piston cores and a trigger core were collected from the slope of Ashmore Trough and dated using radiocarbon and oxygen isotope measurements of planktic foraminifera. Relative abundances, principal component analyses, and cluster analyses of benthic foraminiferal assemblages in sediment... |
Tipo: Text |
Palavras-chave: Papua New Guinea; Margins; Foraminifera. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/00087/19837/17482.pdf |
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Francis, Jason M.; Daniell, James J.; Droxler, Andre W.; Dickens, Gerald R.; Bentley, Samuel J.; Peterson, Larry C.; Opdyke, Bradley N.; Beaufort, Luc. |
The Gulf of Papua (GoP) has become a focal point for understanding the deposition and accumulation of siliciclastic and carbonate material along and across a low-latitude continental margin. Although studies have addressed submarine geomorphological features on the inner and middle shelves, as well as processes that may have led to their formation, the seafloor of adjacent slope regions remains poorly documented. This study presents and interprets results from approximately 13,000 line-km of multibeam bathymetry, 9500 line-km of 3.5 kHz seismic, and 122 sediment cores that were collected from the GoP shelf edge and slope, primarily on two cruises (PANASH and PECTEN). Bathymetric maps, in conjunction with the seismic profiles and cores, were used to make... |
Tipo: Text |
Palavras-chave: Great barrier reef; New Guinea; Platform margin; Foreland basin; OF Papua; Sedimentation; Shelf; Bank; Circulation; Australia. |
Ano: 2008 |
URL: https://archimer.ifremer.fr/doc/00208/31938/30356.pdf |
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Jorry, Stephan; Droxler, Andre W.; Francis, Jason M.. |
The late Quaternary has experienced large glacial/interglacial climatic variations and related 10's to 100 meters high-amplitude sea level fluctuations at Milankovich frequencies from 10's to 100 kyr during which carbonate platform tops have been exposed and re-flooded in many occasions. This study focuses on the accumulation of calci-turbidites, the aragonite onset/sharp increase in fine sediments and their timing in deep basins adjacent to carbonate platforms. A particular emphasis is developed on the occurrence of the first gravity flow event and aragonite onset/sharp increase and their linkage to the initial re-flooding of the platform tops during deglaciations. Three basins adjacent to isolated platforms in the Bahamas, the Northern Nicaragua Rise,... |
Tipo: Text |
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Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00012/12298/9095.pdf |
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Aslanian, Daniel; Moulin, Maryline; Schnurle, Philippe; Klingelhoefer, Fraucke; Leroux, Estelle; Rabineau, Marina; Gailler, Audrey; Bache, Francois; Gorini, Christian; Kuroda, J.; Eguchi, N.; Droxler, Andre W.; Alain, Karine; Roure, François; Haq, B.. |
Tipo: Text |
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Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00149/26055/24160.pdf |
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Regoli, Fabienne; De Garidel-thoron, Thibault; Tachikawa, Kazuyo; Jian, Zhiming; Ye, Liming; Droxler, Andre W.; Lenoir, Guillaume; Crucifix, Michel; Barbarin, Nicolas; Beaufort, Luc. |
The depth of equatorial Pacific thermocline is diagnostic of the main modes of tropical climates. Past estimates of Pacific thermocline dynamics have been reconstructed either for the Last Glacial Maximum or on longer timescales at low resolution. Here we document a new high-resolution set of reconstructed past sea surface and subsurface waters temperatures from the southwestern subequatorial Pacific, core MD05-2930, in the Gulf of Papua, over the last 800 ka. We used two morphotypes of Globigerinoides ruber known to live at different water depths to reconstruct past stratification. We estimated calcification temperature of each morphotypes by Mg/Ca paleothermometry. Our subequatorial Pacific thermocline paleotemperature record indicates a response of the... |
Tipo: Text |
Palavras-chave: Equatorial Pacific; Thermocline; Pleistocene. |
Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00295/40572/39477.pdf |
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Jorry, Stephan J.; Droxler, Andre W.; Mallarino, Gianni; Dickens, Gerald R.; Bentley, Sam J.; Beaufort, Luc; Peterson, Larry C.; Opdyke, Bradley N.. |
Since Last Glacial Maximum (23-19 ka), Earth climate warming and deglaciation occurred in two major steps (Bolling-Allerod and Preboreal), interrupted by a short cooling interval referred to as the Younger Dryas (12.5-11.5 ka B. P.). In this study, three cores (MV-33, MV-66, and MD-40) collected in the central part of Pandora Trough (Gulf of Papua) have been analyzed, and they reveal a detailed sedimentary pattern at millennial timescale. Siliciclastic turbidites disappeared during the Bolling-Allerod and Preboreal intervals to systematically reoccur during the Younger Dryas interval. Subsequent to the final disappearance of the siliciclastic turbidites a calciturbidite occurred during meltwater pulse 1B. The Holocene interval was characterized by a lack... |
Tipo: Text |
Palavras-chave: Younger dryas event; Oxygen isotope records; Meltwater pulse 1a; Great barrier reef; Pacific warm pool; Carbonate platforms; Tropical atlantic; Surface salinity; Nicaragua rise; Caribbean sea. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/00079/19014/16592.pdf |
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Tcherepanov, Evgueni N.; Droxler, Andre W.; Lapointe, Philippe; Dickens, Gerald R.; Bentley, Sam J.; Beaufort, Luc; Peterson, Larry C.; Daniell, James; Opdyke, Bradley N.. |
This paper outlines the evolution of the late Cenozoic mixed carbonate-siliciclastic depositional system in the Gulf of Papua (GoP), using seismic, gravity, multibeam bathymetry, well data sets, and Landsat imagery. The deposition of the mixed sedimentary sequences was influenced by dynamic interplay of tectonics, eustasy, in situ carbonate production, and siliciclastic sediment supply. The roles of these major factors are estimated during different periods of the GoP margin evolution. The Cenozoic mixed system in the GoP formed in distinct phases. The first phase ( Late Cretaceous-Paleocene) was mostly driven by tectonics. Rifting created grabens and uplifted structural blocks which served later as pedestals for carbonate edifices. Active neritic... |
Tipo: Text |
Palavras-chave: Great barrier reef; Sea level; Tectonic controls; Ice volume; Platforms; Sedimentation; Fluctuations; Deposition; Australia; Foreland basin. |
Ano: 2008 |
URL: https://archimer.ifremer.fr/doc/00208/31939/30357.pdf |
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