Polarity chron boundaries and foraminiferal 87Sr/86Sr ratios of ODP Sites 162-986 and 162-987

Cores recovered at Sites 986 and 987 comprise glacial fan sedimentation associated with the Svalbard-Barents Sea and Greenland Ice Sheets, respectively. At Site 986, the top 150 m and the basal 250 m yielded interpretable magnetic stratigraphies. The record from the intervening 550 m is compromised by drilling-related core deformation, poor recovery, and numerous debris flows. The uppermost 150 m appears to record the Brunhes/Matuyama boundary and the Jaramillo Subchron. The base of the drilled section (at ~950 meters below seafloor [mbsf]) is interpreted to lie within the Matuyama Chron (age <2.58 Ma) with an apparent normal polarity interval in the ~730-750 mbsf interval. Dinoflagellate cyst biostratigraphy and Sr isotopic ratios are consistent with a Matuyama age for the base of the drilled section and with the normal polarity interval as the Olduvai Subchron. On the other hand, the last occurrence of Neogloboquadrina atlantica (sinistral) and the last common occurrence of the warm-dwelling Globigerina bulloides at 647-650 mbsf in Hole 986D indicate an age for this level of ~2.3 Ma, inconsistent with the designation of the Olduvai Subchron in the ~730-750 mbsf interval. If the age at 647-650 mbsf in Hole 986D is taken as 2.3 Ma and the base of the hole lies within the Matuyama Chron, then the sedimentation rate in the basal 300 m of the cored section averages 1 m/k.y. At Site 987, the magnetic stratigraphy is fairly unambiguous throughout the section and yields an age of 7.5 Ma (Chron 4n) for the base of the drilled section. The paucity of calcareous and siliceous microfossils precludes biostratigraphic corroboration of the magnetostratigraphic interpretation, although dinoflagellate cysts provide general support, particularly at the base of the section. The age model indicates relatively low sedimentation rates (~5 cm/k.y.) at the base of the section with rates at least four to five times greater during intervals of debris flows at ~5-4.6 and ~2.6 Ma.

(Table 2) Revised stacked record on magnetic susceptibility of ODP Site 162-984 sediments

Magnetic field and susceptibility data were collected using the geological high-resolution magnetometer tool string (GHMT) at three sites during Ocean Drilling Program Leg 162. Postcruise processing of the magnetic field data yielded a polarity stratigraphy for Holes 986C and 987E. A magnetic susceptibility record was measured at Hole 984B. Detailed analysis of the core and log susceptibility records at Hole 984B yielded an empirical tool resolution of the susceptibility measurement tool (SUMT) of 53 cm. At Site 984, where sedimentation rates were typically >10 cm/k.y., this gave a resolution of at least ~5000 yr. This data report summarizes the GHMT postcruise processing, method of interpretation, and analysis of the SUMT resolution.

Polarity chron boundaries and interval sedimentation rates of ODP Leg 162 sites

Magnetic polarity stratigraphies for Sites 980-984 are based on shipboard measurements from the pass-through magnetometer after alternating field (AF) demagnetization at a peak field of 25 mT and shore-based stepwise AF demagnetization of discrete samples. The characteristic magnetization component was determined after AF demagnetization removed the steep downward drill-string-related magnetic overprint. Peak AF fields in the 20-30 mT range were required to resolve the component, carried by magnetite, that was used to produce unambiguous Pliocene-Pleistocene magnetic stratigraphies at all five sites. At Sites 980 and 983, magnetic stratigraphies were resolved to the base of the recovered advanced hydraulic piston corer (APC) section, which lies in the Matuyama Chron (1r.2r) and Olduvai Subchron (2n), respectively. At Sites 981 and 982, magnetization intensities decrease sharply in the normal polarity zone corresponding to the Gauss Chron (2An), and magnetic stratigraphies below this level could not be resolved. At Site 984, the resolution of magnetic stratigraphy was curtailed at ~250 meters below seafloor (Olduvai Subchron) by core deformation at the base of the APC section and in the underlying extended core barrel section. As the magnetic stratigraphies at all four sites are unequivocal, polarity chron interpretations can be made without aid from the biostratigraphy. Mean sedimentation rates within polarity chrons have been calculated and Pliocene-Pleistocene biomagnetostratigraphic correlations tested.

Tarif de quadrature pour le mesurage du sciage des bois, d'après le système métrique, calculé pour toutea les longueurs de madriers, de 1 à 162 décimètres, et les largeurs de 1 à 64 centimètres,

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Tennessee Agricultural and Industrial State University, 1912-1962; fifty years of leadership through excellence, 1912-162.

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El mito de Hylas y la tradición épica en la literatura latina : Una hipótesis de lectura de Juvenal I.162-7

En su primera sátira, Juvenal se encarga de dejar bien claros los motivos por los cuales decidió incluirse dentro de esta tradición. A todas luces programática, la obra adopta la forma de recusatio respecto de varios géneros de los cultivados por sus contemporáneos, pero es principalmente la épica contra la cual parece construirse su futura poética. Hacia el final, antes de que el nuevo ?héroe? Lucilio haga su aparición, son mencionados otros campeones del género, figuras tan representativas como Eneas, Turno y Aquiles. Pero a continuación el satírico sorprende al incluir en el mismo grupo a Hylas, junto a una breve alusión a su rapto. ¿Cómo puede entenderse la introducción de este personaje, tras los típicos héroes griegos y latinos? ¿Qué hay de heroico en él? La historia del rapto de Hylas y la desesperada búsqueda que Heracles comienza es un tema recurrente en la poesía helenística. Particularmente llamativa es la relación entre el tratamiento del mito que hace Apolonio de Rodas en sus Argonáuticas y el de Teócrito en el Idilio XIII. Las tensiones estéticas entre los autores que el tema pone en relieve son heredadas por los poetas latinos, atentos observadores de los modelos alejandrinos. Virgilio hace algunas referencias significativas y desde Propercio hasta la Antigüedad Tardía encontramos obras que desarrollan el mito. Sin embargo, de ninguna de ellas podríamos decir que prime el tono épico. Por lo tanto, este trabajo intenta analizar las diversas plasmaciones del mito en la poesía latina y su relación con las helenísticas. De esta manera, se retomará luego el pasaje de Juvenal conun mejor panorama para comprender qué significa en este contexto la alusión al mito, proponer una lectura posible y conjeturar alguna de sus consecuencias