Age determination, planktic foraminifera and stable istopes of sediment core MSM05/5_712-2

A sediment core from the West Spitsbergen continental margin was studied to reconstruct climate and paleoceanographic variability during the last ~9 ka in the eastern Fram Strait. Our multiproxy evidence suggests that the establishment of the modern oceanographic configuration in the eastern Fram Strait occurred stepwise, in response to the postglacial sea-level rise and the related onset of modern sea-ice production on the shallow Siberian shelves. The late Early and Mid Holocene interval (9 to 5 ka) was generally characterized by relatively unstable conditions. High abundance of the subpolar planktic foraminifer species Turborotalita quinqueloba implies strong intensity of Atlantic Water (AW) inflow with high productivity and/or high AW temperatures, resulting in a strong heat flux to the Arctic. A series of short-lived cooling events (8.2, 6.9. and 6.1 ka) occurred superimposed on the warm late Early and Mid Holocene conditions. Our proxy data imply that simultaneous to the complete postglacial flooding of Arctic shallow shelves and the initiation of modern sea-ice production, strong advance of polar waters initiated modern oceanographic conditions in the eastern Fram Strait at ~5.2 ka. The Late Holocene was marked by the dominance of the polar planktic foraminifer species Neogloboquadrina pachyderma, a significant expansion of sea ice/icebergs, and strong stratification of the water column. Although planktic foraminiferal assemblages as well as sea surface and subsurface temperatures suggest a return of slightly strengthened advection of subsurface Atlantic Water after 3 ka, a relatively stable cold-water layer prevailed at the sea surface and the study site was probably located within the seasonally fluctuating marginal ice zone during the Neoglacial period.

Distribution and abundance of calcareous-nannoplankton species in the Cretaceous sediments of DSDP Leg 62 Holes

Cretaceous sediments were recovered at all four sites (Sites 463-466) of the central North Pacific drilled during Leg 62 of the Deep Sea Drilling Project. One of the objectives was to get more information about the development of ocean plankton communities and early evolution of planktonic groups of the Mesozoic. In this article, the Cretaceous calcareous nannofossils from two areas of the central North Pacific (Mid-Pacific Mountains and Hess Rise) are listed and discussed. (The Cenozoic calcareous nannofossils are discussed by R. Schmidt 1981). Coring was continuous at all sites. Mesozoic calcareous nannoplankton assemblages range on the Mid-pacific Mountains from Barremian to Early Maastrichtian, and on Hess Rise from Albian to Late Maastrichtian. (No calcareous nannofossils older than Barremian or Albian respectively were found).

Daniel Cravacuore, Sergio Ilari y Alejandro Villar, La articulación en la gestión municipal. Actores y políticas

Fil: Chain, Leyla Inés. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación; Argentina.

Una materialidad de la exasperación. Acerca de Poesía civil, de Sergio Raimondi

Con la publicación de Poesía civil, Sergio Raimondi (Bahía Blanca, 1968) se ha colocado en un lugar central de la poesía argentina contemporánea. El presente artículo indaga las relaciones complejas entre estética y política, y entre poesía y sociedad configuradas en el texto, a partir de una visión materialista formalizada en su escritura. El fuerte antilirismo del texto pone en cuestión nociones teóricas como las de "límite" y "género", que enfatizan el procesamiento de discursos "extraliterarios" o "extrapoéticos". A su vez, la noción de "paisaje" resulta clave en la disposición de una mirada realista que, al particularizar la representación estética, da lugar a lo histórico y produce formalmente su efectividad política.

La Rédaction. Musée de la Maison d'École à Montceau-les-Mines, Groupe de recherche pédagogique, Cahier numéro 1, 2009, 62 páginas

Fil: Peláez, Agustina. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación; Argentina.

"Cómo intentar atrapar nubes con una red". De las definiciones objetivas a las prácticas de producción cultural de las clases medias : Reseña de Visacovsky, Sergio y Garguin, Enrique, compiladores (2009), Moralidades, economías e identidades de la clase media. Estudios históricos y etnográficos, Buenos Aires, Antropofagia, 366 páginas

Fil: Iuliano, Rodolfo. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación. Instituto de Investigaciones en Humanidades y Ciencias Sociales (UNLP-CONICET); Argentina.

XRF scanning, pollen and spores of ODP Site 108-659

Pliocene vegetation dynamics and climate variability in West Africa have been investigated through pollen and XRF-scanning records obtained from sediment cores of ODP Site 659 (18°N, 21°W). The comparison between total pollen accumulation rates and Ti/Ca ratios, which is strongly correlated with the dust input at the site, showed elevated aeolian transport of pollen during dusty periods. Comparison of the pollen records of ODP Site 659 and the nearby Site 658 resulted in a robust reconstruction of West African vegetation change since the Late Pliocene. Between 3.6 and 3.0 Ma the savannah in West Africa differed in composition from its modern counterpart and was richer in Asteraceae, in particular of the Tribus Cichorieae. Between 3.24 and 3.20 Ma a stable wet period is inferred from the Fe/K ratios, which could stand for a narrower and better specified mid-Pliocene (mid-Piacenzian) warm time slice. The northward extension of woodland and savannah, albeit fluctuating, was generally greater in the Pliocene. NE trade wind vigour increased intermittently around 2.7 and 2.6 Ma, and more or less permanently since 2.5 Ma, as inferred from increased pollen concentrations of trade wind indicators (Ephedra, Artemisia, Pinus). Our findings link the NE trade wind development with the intensification of the Northern Hemisphere glaciations (iNHG). Prior to the iNHG, little or no systematic relation could be found between sea surface temperatures of the North Atlantic with aridity and dust in West Africa.