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[en] Rainfall at two stations in the Shephela (Israel Coastal Plain) was analyzed for 210Pb during the winter of 1974-75. The highest concentrations of 210Pb were found in samples collected early in the rainy season. It seemed that there was a small, but significant difference between the two stations. The total activity at the Bet-Dagan station (near Tel-Aviv) and generally also the activities in the individual samples collected at this station were lower than the respective activities at the Gan-Shomron station (60 kms to the north)
[en] Lead-210 dating can be applied over a time-scale of about 100 years. The source of the 210Pb in the 238U radioactive decay series, and the factors affecting its distribution are discussed. The methodology of 210Pb dating is outlined, and those factors that must meet strict requirements for successful results are described. Examples of applications of 210Pb dating are presented, with preliminary results for one Victorian lake
[en] Radioactive particle movement analysis in any environment gives valuable information about the effects of the concerned environment on the particle and the transportation phenomenon. In this study, the spatio-temporal point cumulative semivariogram (STPCSV) approach is proposed for the analysis of the spatio-temporal changes in the radioactive particle movement within a surface water body. This methodology is applied to the 210Pb radioactive isotope measurements at 44 stations, which are determined beforehand in order to characterize the Keban Dam water environment on the Euphrates River in the southeastern part of Turkey. It considers the contributions coming from all the stations and provides information about the spatio-temporal behavior of 210Pb in the water environment. After having identified the radii of influences at each station it is possible to draw maps for further interpretations. In order to see holistically the spatial changes of the radioisotope after 1st, 3rd and 5th hours, the radius of influence maps are prepared and interpreted accordingly.
[en] To illustrate some of the diverse applications of coastal sediment radiochronology with 210Pb, in this chapter we briefly introduce examples coming mostly from Latin America. Though we recommend reading the original sources, we hope this summary helps choose those that seem most appropriate to each investigator. In the literature of the various chapters one can also find other great examples.
[es]Para ilustrar algunas de las muy diversas aplicaciones de la radiocronologia de sedimentos costeros con 210Pb, en este capitulo introducimos brevemente ejemplos que proceden mayoritariamente de Iberoamerica. Aunque recomendamos la lectura de las fuentes originales, esperamos que este resumen ayude a elegir aquellas que parezcan mas adecuadas a cada investigador. En la bibliografia de los diversos capitulos pueden encontrar tambien otros excelentes ejemplos.
[en] This chapter provides a general overview of the occurrence, behaviour and cycling of 210Pb and 210Po in the environment and covers some major concepts and pathways. The data presented give a feeling for the orders of magnitude of activity concentrations which can be expected in environmental media and the relative importance of various pathways. However, the information is not comprehensive, nor does it provide details of the mechanisms involved. Environmental media and pathways are discussed in more detail in Chapters 5-10, including data on activity concentrations, transfer parameters and fluxes.
[en] The use of natural radioactivity in environmental studies is a very powerful tool to determine the dynamics of both natural and anthropogenic processes in our environment. The use of 14C in archaeology and past climate studies has led to many scientific discoveries. Carbon-14 dating is limited to a time scale from about 400 to about 40,000 years before present. The use of the 238U-decay series is of at least equal value to studies in archaeology and past climates. Some of the isotopes in this decay series can be used for dating up to 350,000 years and others can be utilised to date vary young systems in which 14C is of little use. (author). 12 refs., 4 figs.
[en] In this chapter we describe techniques for collecting sediment cores for obtaining geochronologies by 210Pb (100 years) to allow historical reconstruction of environmental changes in the coastal zone. We examine relevant aspects for the sampling design, mainly related to the basic information about the area of interest necessary to choose the perfect place sampling, thereby we can improve the chances of success in meeting the objectives of the study. We also include description of the sampling methods aimed at maximizing the collecting capabilities of undisturbed sedimentary material, emphasizing the recovery of unaltered sediment-water interface. In addition, we describe subsampling procedures and sample handling intended to minimize post-sampling disruption to improve the possibilities of a reconstruction of reliable geochronologies.
[es]En este capitulo describimos tecnicas de recogida de cores sedimentarios para la obtencion de geocronologias por 210Pb (100 anos) que permitan la reconstruccion historica de cambios ambientales en la zona costera. Examinamos los aspectos relevantes para el diseno del muestreo, principalmente relacionados con la informacion basica sobre el area de interes necesaria para escoger el lugar idoneo de muestreo. De ese modo podemos mejorar las posibilidades de exito en el cumplimiento de los objetivos del estudio. Incluimos ademas la descripcion de los metodos de muestreo orientados a maximizar las posibilidades de recogida de material sedimentario no perturbado, poniendo enfasis en la recuperacion inalterada de la interfase agua-sedimento. Asimismo, describimos procedimientos de submuestreo y manipulacion de muestras, con los cuales se pretende minimizar la perturbacion post-muestreo para mejorar las posibilidades de una reconstruccion de geocronologias confiables.