Investigation of Quaternary foraminifera in sediment core CRP-1 from the Ross Sea, Antarctica

Foraminifera are examined in twenty-six samples from a 44 metre succession of Quaternary glacial sediments recovered from the CRP-1 drillhole on Roberts Ridge, southwestern Ross Sea, Antarctica. In situ marine assemblages were documented in at least three of the six lithostratigraphic units, and it is likely that the remaining three interbedded diamicton units are also marine in origin. Peak foraminiferal diversities are documented in Unit 3.1 (73 species) and Unit 2.2 (32 species). Calcareous benthics dominate the assemblages, but may be accompanied by abundant occurrences of the planktonic Neogloboquadrina pachyderma. Low diversity agglutinated faunas appear in the uppermost strata of Units 4.1 and 2.2. A close relationship between lithofacics and foraminiferal biofacies points to marine environments that alternated between proximity to and distance from active glaciers and iceshelf fronts, with associated variations in salinity, sea-surface ice cover and the levels of rainout from debris-laden ice.

Contents of organic compounds in sediments from DSDP Legs 1 and 4

Fifteen sediment samples were studied from five drill sites recovered by the Glomar Challenger on Legs I and IV in the Gulf of Mexico and western Atlantic. This study concentrated on compounds derived from biogenic precursors, namely: (1) hydrocarbons, (2) fatty acids, (3) pigments and (4) amino acids. Carbon isotope (dC13) data [values <(-26)?, relative to PDB], long-chain n-alkyl hydrocarbons (>>C27) with odd carbon numbered molecules dominating even carbon numbered species, and presence of perylene proved useful as possible indicators for terrigenous contributions to the organic matter in some samples. Apparently land-derived organic matter can be transported for distances over 1000 km into the ocean and their source still recognized. The study was primarily designed to investigate: (i) the sources of the organic matter present in the sediment, (ii) their stability with time of accumulation and (iii) the conditions necessary for in situ formation of new compounds.

(Appendix 1) Age, Ge/Si ratio, aluminium and opal contents in ODP Sites 175-1081 and 175-1084

As a result of both culture and sediment core studies, the ratio of germanium (Ge) to silicon (Si) in diatom shells has been proposed as a proxy for monitoring whole-ocean changes in seawater Ge/Si, a ratio affected by changes in continental weathering. However, because of the difficulties of extracting and cleaning diatom frustules from deep-sea sediments, only samples from highly pure diatom oozes in the Antarctic region have been previously analyzed. Here we present data on diatom Ge/Si ratios, (Ge/Si)opal, for the time interval between 3.1 and 1.9 Ma from a mid-latitude, coastal upwelling area where significant terrigenous sediment input complicated the sample processing and analyses. In general, our (Ge/Si)opal values show the same decreasing trend after 2.6 Ma than previously measured in Antarctic sediments (Shemesh et al., 1989. Paleoceanography 4, 221-231), but with a noisier background that may reflect the local imprint of proximal continental input superimposed upon global changes in the ocean reservoir. The time of initiation of large-scale North Hemisphere glaciation at ~2.6 Ma is characterized by a declining pattern of diatom Ge/Si ratios, which could have resulted from a global increase in the input of riverine Si due to enhanced silica weathering and/or equatorward (northward) intrusions of subantarctic waters enriched in silica. High (Ge/Si)opal ratios are associated with high opal contents from the same sediment samples and with warm climate as indicated by depleted benthic foraminiferal d18O values from the North and Equatorial Atlantic. Cold periods signified by enriched benthic d18O values, on the contrary, are associated with lower (Ge/Si)opal ratios. We interpret diatom Ge/Si values to reflect the prevailing weathering state on the continents, with greater chemical weathering during warm and wet periods of the Pliocene and less during cooler and drier intervals.

Representaciones de la vejez y formas del discurso ejemplar romano durante el S. I d.C.

Examinaremos cómo la vejez en el corpus fedriano se configura a partir de los diálogos que este establece con sus contextos literarios y culturales. Así, la construcción de la ancianidad femenina incorpora estereotipos cómicosatíricos que evidencian la perspectiva romanocéntrica desde la que el género se reformula (Phaed.2.2 y 3.1). Por su parte, la debilidad atribuida a los ancianos (Phaed.1.15 y 1.21) -leída en contraposición con la fortaleza que su contemporáneo, Valerio Máximo, adjudica a la ancianidad modélica en sus exempla (V. Max. 8.13)- contribuye a la construcción de la máscara del fabulista como sujeto marginal (3. 9 y 3. epil.).

Petonii Curiosa Felicitas : La función de las citas en el discurso de Eumolpo (Sat. 118)

Este trabajo analiza el fenómeno intertextual de la ?cita? en Petronio, Sat. 118, donde el poeta de la obra, Eumolpo, expone su particular ?ars poetica?. En este discurso, Eumolpo cita los nombres de Homero, Virgilio y Horacio, al tiempo que cita el primer verso de la Oda 3.1 del Venusino, lo que evidencia que el poetastro tiene muy en cuenta la figura horaciana. El análisis de las citas en este pasaje se relaciona con que Petronio es un autor que alude constantemente, pero que cita muy rara vez, por lo que, cuando lo hace, se debe prestar mucha atención

Petonii Curiosa Felicitas : La función de las citas en el discurso de Eumolpo (Sat. 118)

Este trabajo analiza el fenómeno intertextual de la ?cita? en Petronio, Sat. 118, donde el poeta de la obra, Eumolpo, expone su particular ?ars poetica?. En este discurso, Eumolpo cita los nombres de Homero, Virgilio y Horacio, al tiempo que cita el primer verso de la Oda 3.1 del Venusino, lo que evidencia que el poetastro tiene muy en cuenta la figura horaciana. El análisis de las citas en este pasaje se relaciona con que Petronio es un autor que alude constantemente, pero que cita muy rara vez, por lo que, cuando lo hace, se debe prestar mucha atención