Presencia de radionucleidos en arcillas del sistema hidrotermal del Volcán Turrialba, Costa Rica
Date
Authors
García Vindas, José Ralph
Gazel Dondi, Esteban
Journal Title
Journal ISSN
Volume Title
Publisher
Universidad de Costa Rica
Abstract
Description
Los primeros resultados de un estudio sobre la presencia de algunos radionucleidos de origen terrígeno, son presentados para el sistema hidrotermal del volcán Turrialba. Se tomaron muestras de arcillas en variospuntos de los cráteres central y suroeste y se analizaron mediante espectrometría gamma de bajo nivel, usando undetector de germanio hiperpuro. Se reportan los valores de las actividades en Bq/kg, de los isótopos radiactivos naturales detectados. Se encontró un desequilibrio en la serie del U-238, el cual es explicado por dos mecanismos diferentes: uno de índole convectivo y el otro por enriquecimiento de Rn-222. Se observa un aumento en la actividad de todos los isótopos entre setiembre del 2001 y mayo del 2002. Dada la poca probabilidad de que este aumento se deba a la escorrentía superficial, se propone que el aumento de la concentración de estos elementos puede serocasionado por su llegada en la fase gaseosa, suspendidos en el vapor de agua y otros gases volcánicos.
The first results obtained about the presence of radionucleids of terrigenous origin in the hydrothermal system of Turrialba Volcano are shown in this paper. Several samples were taken in the central and southwest craters, and analyzed by gammaray spectrometry, with a Hyperpure Germanium detector. The values ofthe activities of the natural radioactive isotopes are shown in Bq/kg. A disequilibrium in the series of U-238 wasfound, which is explained by two different mechanisms: one convective and the other by Rn222 enrichment. An increase of the activity of all isotopes is observed between September 2001 and May 2002. Because the lowpossibilities that this can be produced by the water runoff, it it proposed that such rise in the concentration ofthe elements can be explained by their presence in the water vapour and other volcanic gases.
The first results obtained about the presence of radionucleids of terrigenous origin in the hydrothermal system of Turrialba Volcano are shown in this paper. Several samples were taken in the central and southwest craters, and analyzed by gammaray spectrometry, with a Hyperpure Germanium detector. The values ofthe activities of the natural radioactive isotopes are shown in Bq/kg. A disequilibrium in the series of U-238 wasfound, which is explained by two different mechanisms: one convective and the other by Rn222 enrichment. An increase of the activity of all isotopes is observed between September 2001 and May 2002. Because the lowpossibilities that this can be produced by the water runoff, it it proposed that such rise in the concentration ofthe elements can be explained by their presence in the water vapour and other volcanic gases.
Keywords
radionucleidos, arcillas, sistema hidrotermal, volcán Turrialba, gases volcánicos, radionucleids, clays, hydrothermal system, turrialba volcano, volcanic gases