Mineralogy at DSDP Legs 58-60

Sediments recovered by drilling during Legs 58, 59, and 60 in the North and South Philippine Sea have been analyzed by X-ray diffractometry. The CaCO3 content was measured separately. The sites encompass several volcanic ridges and intervening inter-arc basin troughs as well as sites on the Mariana arc fore-arc sediment prism and the Mariana Trench. The sediments at all sites received major volcanogenic input from the various arcs; they tend to be rich in volcanic glass, with associated quartz, feldspar, pyroxenes and amphibole. Carbonate is a major component only at Site 445 at the southern end of the Daito Ridge, and at Site 448 on the Palau-Kyushu Ridge. All other sites were either deep relative to the carbonate compensation depth or had very high non-carbonate sedimentation rates. Clay minerals are mainly smectite and illite with lesser variable proportions of chlorite and kaolinite. Smectite predominates over illite except at sites in the Shikoku Basin and the Daito Ridge, and at one site in the Mariana Trench. At several sites, smectite increases and illite decreases with depth. Principal zeolites are phillipsite and clinoptilolite. Analcime occurs in some samples.

Las "marcas de la historia" en el origen y desarrollo de las ciencias políticas en la Universidad Nacional de Cuyo entre los '60 y los '70

Este artículo es un avance del proyecto de investigación acerca de la historia social de la carrera de Ciencia Política de la Universidad Nacional de Cuyo, en cuya primera etapa se abordó el período que va entre los años '60 hasta el golpe militar de 1976. Este avance consiste en la revisión de ciertos aspectos relevantes como el análisis de los boletines y cuadernos de estudio, reformas de los planes de estudio y sus respectivas ordenanzas, además de entrevistas a docentes e investigadores de la época. Consideramos que estos aspectos son importantes para advertir y comprender las «marcas de la historia» en el origen y desarrollo de esta disciplina científica en la provincia de Mendoza y para avanzar en la elaboración de una historia social de la misma.

(Table 1) Oxygen isotope temperatures from hydrothermally altered breccias at DSDP Hole 60-453

Gabbro-metabasalt polymict breccias cored in Deep Sea Drilling Project Hole 453 are cemented in part by hydrothermal alteration to lower greenschist facies (chlorite-epidote-actinolite) mineral assemblages. Temperature estimates for this alteration, based on oxygen isotope determinations of secondary minerals, are nearly 100°C at the top of the breccias and over 200°C in a zone of intense alteration near the base.