%0 Journal Article
%T Grain Size Analysis and Clay Mineral Associations in Bottom Sediments From Paran¨¢ River Basin
%A Marcelo Manassero
%A Cecilia Camili¨®n
%A Daniel Poir¨¦
%A Mario Da Silva
%J Latin American Journal of Sedimentology and Basin Analysis
%D 2008
%I Asociaci¨®n Argentina de Sedimentolog¨ªa
%X Three different clay mineral assemblages are detected in mud-sandy bottom sediments of the Paran¨¢ Basin of Argentina. A dominant Kaolinite association, with sources areas in the Upper Amazon, north-east of the study area and within the Brazilian Shield (also with subordinated crystalline Illite); an Illitic- Smectitic and Interlayer I/S association, from the Andean Cordillera and the Chaco Plains in the north-west and mainly represented by the Bermejo and Pilcomayo Rivers; a southern Illitic-Chlorite dominant, but with lower crystallinity index than in the northern area, whose source is in the Pampean Plains to the west of Argentina. Mixed layer clays (Illite/Smectite) were also detected in this southern sector. These clay mineral associations reflect not only the climate but the source rock composition in these three main geographical areas. The tributaries of the lower Paran¨¢ River Basin show a dominant Illitic-Smectitic clay mineral association that has been eroded and transported from the Pampean Plains. In this contribution, three main clay mineral associations (Illite-Chlorite, Smectite-I/S, and Kaolinite) in stream sediments of the Paran¨¢ River and tributaries within a wide area of Argentina are described and their provenance is interpreted on the basis of controlling factors, climate and provenance. Se describen tres asociaciones de argilominerales presentes en sedimentos de fondo limo-arcillosos del r¨ªo Paran¨¢ y algunos de sus tributarios en Argentina. Una asociaci¨®n con Caolinita (con Illita cristalina subordinada) y con ¨¢reas de aporte hacia el noreste de la zona de estudio, en el Alto Amazonas y el Macizo Brasile o, una asociaci¨®n de Illita-Esmectita e interestratificado Esmectita/ Illita, procedente de la Cordillera Andina y las Planicies del Chaco ubicadas hacia el noroeste y representadas por los r¨ªos Bermejo y Pilcomayo y una asociaci¨®n de Illita-Clorita dominante, de menor ¨ªndice de cristalinidad que las del ¨¢rea norte, procedente de las Planicies Pampeanas de Argentina hacia el oeste. Argilominerales interestratificados de tipo Illita/ Esmectita son tambi¨¦n descriptos en este sector sur. Las asociaciones de arcilla reflejan tanto la influencia del clima como a la litolog¨ªa y composici¨®n de estas ¨¢reas de aporte. Los tributarios del r¨ªo Paran¨¢ Inferior muestran una composici¨®n de argilominerales dominante, de tipo Illita-Esmectita con proveniencia de las Planicies Pampeanas. En esta contribuci¨®n tres asociaciones de argilofacies (Illita-Clorita, Illita- Esmectita interestratificado y Caolinita) en los sedimentos de fondo de los tributar
%K Sedimentos de fondo
%K Textura
%K Argilominerales
%K R¨ªo Paran¨¢ y tributarios
%K Bottom sediments
%K Grain size
%K Clay minerals
%K Paran¨¢ River and tributaries
%U http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S1851-49792008000200004