Stable carbon and oxygen isotope compositions of benthic foraminifera N. truempyi samples and coarse fraction analyses from ODP Site 198-1209

We have compiled the first stratigraphically continuous high-resolution benthic foraminiferal stable isotope record for the Paleocene from a single site utilizing cores recovered at Pacific ODP Site 1209. The long-term trend in the benthic isotope record suggests a close coupling of volcanic CO2 input and deep sea warming. Over the short-term the record is characterized by slow excursions with a pronounced periodic beat related to the short (100-kyr) and long (405-kyr) eccentricity cycle. The phase relationship between the benthic isotope record and eccentricity is similar to patterns documented for the Oligocene and Miocene confirming the role of orbital forcing as the pace maker for paleoclimatic variability on Milankovitch time scales. In addition, the record documents an unusual transient warming of 2°C coeval with a 0.6 per mil carbon isotope excursion and a decrease in carbonate content at 61.75 Ma. This event, which bears some resemblance to Eocene hyperthermals, marks the onset of a long-term decline in d13C. The timing indicates it might be related to the initiation of volcanism along Greenland margin.

Anthony Giddens. La tercera vía. La renovación de la socialdemocracia. Taurus, Madrid, 1999, 198 páginas. (edición original en inglés de 1998)

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

Dupuy, Andrea. 2004. El fin de una sociedad de frontera en la primera mitad del siglo XIX. Hacendados y estancieros en Pergamino. Mar del Plata: Universidad Nacional de Mar del Plata. 198 p.

Fil: Huarte, Germán A.. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación; Argentina.

Revised composite depth scales for ODP sites 198-1209, 198-1210 and 198-1211, Shatsky Rise

We present new revised composite depth scales for Ocean Drilling Program Leg 198 Sites 1209, 1210, and 1211, drilled at Shatsky Rise in the western Pacific Ocean. Reinterpretation of high-resolution physical property data, with the main focus on magnetic susceptibility as the primary parameter for hole-to-hole correlation, revealed that the shipboard composite records had to be revised below 124.87 meters composite depth (mcd) for Site 1209, below 142.45 mcd for Site 1210, and below 88.64 mcd for Site 1211. The revised composite records comprise Paleogene and Cretaceous sediments at all three sites. As a result of the additional adjustments, the revised mcd records of Sites 1209 and 1210 are 13.48 and 2.69 m longer than the original spliced records, respectively. The original splice of Site 1211 has undergone minor adjustments only to match those of Sites 1209 and 1210. Moreover, detailed correlation of sections outside the new spliced records enable samples already taken to be placed into the new revised composite depth scale.

Anthony Giddens. La tercera vía. La renovación de la socialdemocracia. Taurus, Madrid, 1999, 198 páginas. (edición original en inglés de 1998)

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

Dupuy, Andrea. 2004. El fin de una sociedad de frontera en la primera mitad del siglo XIX. Hacendados y estancieros en Pergamino. Mar del Plata: Universidad Nacional de Mar del Plata. 198 p.

Fil: Huarte, Germán A.. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación; Argentina.

Age and petrographic characterization of volcanic ash from ODP Leg 198 and Leg 126 sites

In this study of volcanic ash retrieved from Shatsky Rise during Ocean Drilling Program Leg 198, the texture and composition of the volcanic components (glass and crystals) were used to fingerprint ash layers for detailed correlation. Correlations among ash layers in holes drilled at the same site as well as between sites, including sites on different parts (highs) of the rise, were tested. Although high-to-high correlations failed, intrahigh correlations were more successful. Our data suggest a significantly different source for some pyroclastic debris, especially at Site 1208, possibly associated with pumice rafts carried northward from the Izu-Bonin arc by the Kuroshio Current. Other ashes are consistent with rhyolitic to dacitic air fall ash from Asian arc volcanoes. We were not able to texturally distinguish between air fall ash and pumice-raft fallout but suspect that the latter is associated with higher percentages of vesiculated ash components, as we demonstrate occur in more proximal Izu-Bonin pyroclastic deposits.