Entre puertos, campos y acopios : Trabajo y transporte de granos en torno al Sudeste bonaerense

En este artículo, se analiza el proceso de trabajo en el transporte automotor de granos en torno al sudeste bonaerense. Desde un abordaje cualitativo, se describen y analizan las prácticas durante la cosecha y pos-cosecha, y los trayectos campo-acopio, acopio-puerto. También se analizan las relaciones laborales a partir de una perspectiva ampliada de las relaciones laborales clásicas (asalariadas, estables, protegidas).Los rasgos que asume el trabajo en el transporte de granos están asociados a los cambios técnicos y tecnológicos de la producción de granos, así como a procesos de flexibilización laboral, vinculados a la disponibilidad permanente para fletar, la extensión de la jornada laboral y la intensidad del trabajo camionero

Mineralogical and grain size analysis of ODP Hole 119-745B from the Southern Ocean

The upper Miocene to Pleistocene sediments recovered at ODP Sites 745 and 746 in the Australian-Antarctic Basin are characterized by cyclic facies changes. Sedimentological investigations of a detailed Quaternary section reveal that facies A is dominated by a high content of siliceous microfossils, a relatively low terrigenous sediment content, an ice-rafted component, low concentrations of fine sediment particles, and a relatively high smectite content. This facies corresponds to interglacial sedimentary conditions. Facies B, in contrast, is characteristic of glacial conditions and is dominated by a large amount of terrigenous material and a smaller opaline component. There is also a prominent ice-rafted component. The microfossils commonly are reworked and broken. The clay mineral assemblages show higher proportions of glacially derived illite and chlorite. A combination of four different processes, attributed to glacial-interglacial cycles, was responsible for the cyclic facies changes during Quaternary time: transport by gravity, ice, and current and changes in primary productivity. Of great importance was the movement of the grounding line of the ice shelves, which directly influenced the intensity of ice rafting and of gravitational sediment transport to the deep sea. The extension of the ice shelves was also responsible for the generation of cold and erosive Antarctic Bottom Water, which controlled the grain-size distribution, particularly of the fine fraction, in the investigated area.

Entre puertos, campos y acopios : Trabajo y transporte de granos en torno al Sudeste bonaerense

En este artículo, se analiza el proceso de trabajo en el transporte automotor de granos en torno al sudeste bonaerense. Desde un abordaje cualitativo, se describen y analizan las prácticas durante la cosecha y pos-cosecha, y los trayectos campo-acopio, acopio-puerto. También se analizan las relaciones laborales a partir de una perspectiva ampliada de las relaciones laborales clásicas (asalariadas, estables, protegidas).Los rasgos que asume el trabajo en el transporte de granos están asociados a los cambios técnicos y tecnológicos de la producción de granos, así como a procesos de flexibilización laboral, vinculados a la disponibilidad permanente para fletar, la extensión de la jornada laboral y la intensidad del trabajo camionero

Clay mineraology and grain size composition of surface sediments from South Pacific Ocean

The reconstruction of low-latitude ocean-atmosphere interactions is one of the major issues of (paleo-)environmental studies. The trade winds, extending over 20° to 30° of latitude in both hemispheres, between the subtropical highs and the intertropical convergence zone, are major components of the atmospheric circulation and little is known about their long-term variability on geological time-scales, in particular in the Pacific sector. We present the modern spatial pattern of eolian-derived marine sediments in the eastern equatorial and subtropical Pacific (10°N to 25°S) as a reference data set for the interpretation of SE Pacific paleo-dust records. The terrigenous silt and clay fractions of 75 surface sediment samples have been investigated for their grain-size distribution and clay-mineral compositions, respectively, to identify their provenances and transport agents. Dust delivered to the southeast Pacific from the semi- to hyper-arid areas of Peru and Chile is rather fine-grained (4-8 µm) due to low-level transport within the southeast trade winds. Nevertheless, wind is the dominant transport agent and eolian material is the dominant terrigenous component west of the Peru-Chile Trench south of ~ 5°S. Grain-size distributions alone are insufficient to identify the eolian signal in marine sediments due to authigenic particle formation on the sub-oceanic ridges and abundant volcanic glass around the Galapagos Islands. Together with the clay-mineral compositions of the clay fraction, we have identified the dust lobe extending from the coasts of Peru and Chile onto Galapagos Rise as well as across the equator into the doldrums. Illite is a very useful parameter to identify source areas of dust in this smectite-dominated study area.

Carbonate and bulk grain-size record for ODP Leg 130 holes

A major goal of Ocean Drilling Program (ODP) Leg 130 was to drill four sites down the northeastern flank of the Ontong Java Plateau to collect a series of continuous sedimentary sequences that would provide a depth transect of Neogene sediments. In particular, the study of the sediments recovered along the depth transect is expected to yield high-resolution stratigraphic, geochemical, and physical properties records across intervals of major paleoceanographic changes by evaluating variations of primary sedimentological and paleoceanographic indicators (e.g., carbonates, isotopes, grain size, microfossil assemblages, etc.). This data report presents the results of highresolution (3-5 Ka sample intervals) analyses of carbonate concentration and bulk sediment grain size at Sites 803-806 for the time interval from 2 Ma to the present.

Entre puertos, campos y acopios : Trabajo y transporte de granos en torno al Sudeste bonaerense

En este artículo, se analiza el proceso de trabajo en el transporte automotor de granos en torno al sudeste bonaerense. Desde un abordaje cualitativo, se describen y analizan las prácticas durante la cosecha y pos-cosecha, y los trayectos campo-acopio, acopio-puerto. También se analizan las relaciones laborales a partir de una perspectiva ampliada de las relaciones laborales clásicas (asalariadas, estables, protegidas).Los rasgos que asume el trabajo en el transporte de granos están asociados a los cambios técnicos y tecnológicos de la producción de granos, así como a procesos de flexibilización laboral, vinculados a la disponibilidad permanente para fletar, la extensión de la jornada laboral y la intensidad del trabajo camionero

Grain size analyses of ODP Leg 178 sites

Sites 1095, 1096, and 1101 were drilled on the continental rise west of the Antarctic Peninsula (Fig. F1) to recover a continuous high-resolution record of Antarctic glaciation. Site 1095 is the subject of a short paper in this volume (Pudsey, 2001, doi:10.2973/odp.proc.sr.178.214.2001), whereas mass accumulation rates at the three sites are described by Wolf-Welling (2001, doi:10.2973/odp.proc.sr.178.223.2001) and ice-rafted debris at Site 1101 is discussed by Cowan (2001, doi:10.2973/odp.proc.sr.178.206.2001) This report documents grain-size data (sand and fine fraction) and the proportion of biogenic silica for the upper 300 m at Site 1095, the upper 250 m at Site 1096, and the whole 220 m at Site 1101.

Grain size composition of marine and river bottom sediments

According to average grain size parameters (Kd, Kd1) recent sediments from the northern Caspian Sea and the Barents Sea shelf are similar, while sediments from the Norwegian Sea are closer to their counterparts of the World Ocean. Seaward content of subcolloidal (<0.001 mm) size fraction increases against the background of decreasing proportions of coarse- and medium-grained pelite (<0.01 mm) material.

Grain size analyses of ODP Leg 116 holes

Ocean Drilling Program (ODP) Leg 116 cored the distal part of the Bengal Fan at three closely spaced sites (717-719). The recovered sediments consisted dominantly of turbidites that varied in thickness between a few centimeters and 2 m or more. A number of different facies have been identified in the sequence and are described by Stow et al. (1990, doi:10.2973/odp.proc.sr.116.110.1990). Representative examples of these facies types were selected and sampled for grain-size analysis. The results of these analyses are tabulated in this data report.

Entre puertos, campos y acopios : Trabajo y transporte de granos en torno al Sudeste bonaerense

En este artículo, se analiza el proceso de trabajo en el transporte automotor de granos en torno al sudeste bonaerense. Desde un abordaje cualitativo, se describen y analizan las prácticas durante la cosecha y pos-cosecha, y los trayectos campo-acopio, acopio-puerto. También se analizan las relaciones laborales a partir de una perspectiva ampliada de las relaciones laborales clásicas (asalariadas, estables, protegidas).Los rasgos que asume el trabajo en el transporte de granos están asociados a los cambios técnicos y tecnológicos de la producción de granos, así como a procesos de flexibilización laboral, vinculados a la disponibilidad permanente para fletar, la extensión de la jornada laboral y la intensidad del trabajo camionero