Consulta: subjectFacets:"Clay mineralogy"
Registros recuperados: 3
Data/hora: 12/06/2024 17:09:13

Constraints on Black Sea outflow to the Sea of Marmara during the last glacial-interglacial transition
Provedor de dados: 5
Autores: Major, Candace; Ryan, William; Lericolais, Gilles; Hajdas, Irka.
New cores from the upper continental slope off Romania in the western Black Sea provide a continuous, high-resolution record of sedimentation rates, clay mineralogy, calcium carbonate content, and stable isotopes of oxygen and carbon over the last 20000 yr in the western Black Sea. These records all indicate major changes occurring at 15 000, 12 800, 8400, and 7 100 yr before present. These results are interpreted to reflect an evolving balance between water supplied by melting glacial ice and other river runoff and water removed by evaporation and outflow. The marked retreat of the Fennoscandian and Alpine ice between 15 000 and 14 000 yr is recorded by an increase in clays indicative of northern provenance in Black Sea sediments. A short return toward...
Tipo: Text
Palavras-chave: Clay mineralogy; Stable isotopes; Sapropel; Younger Dryas; Deglaciation.
Ano: 2002
URL: http://archimer.ifremer.fr/doc/2002/publication-473.pdf

Link between Indian monsoon rainfall and physical erosion in the Himalayan system during the Holocene
Provedor de dados: 5
Autores: Joussain, Ronan; Liu, Zhifei; Colin, Christophe; Duchamp-alphonse, Stephanie; Yu, Zhaojie; Moreno, Eva; Fournier, Lea; Zaragosi, Sebastien; Dapoigny, Arnaud; Meynadier, Laure; Bassinot, Franck.
Mineralogical and geochemical analyses conducted on cores located on the active channel-levee system of the northern Bengal Fan are used to establish changes in the weathering pattern and the sediment transport of the Himalayan system, and evaluate the effect of Indian summer monsoon rainfall during the Holocene. Our data indicate that during the Holocene, sediments from the northern Bengal Fan originate mainly from the G-B river system without any significant changes in the relative contribution of these rivers. From 9.8 to around 6 ka, relatively low smectite/(illite+chlorite) ratios and relatively high K/Si* ratios indicate high physical denudation rates of the Himalayan highlands together with a rapid transfer of the detrital material to the Bengal...
Tipo: Text
Palavras-chave: Bengal Fan; Chemical weathering; Sr and Nd isotopic compositions; Physical erosion; Clay mineralogy.
Ano: 2017
URL: https://archimer.ifremer.fr/doc/00393/50416/51143.pdf

Mineralogy of the Clay Fraction and Chemical Properties of Soils Developed from Sedimentary Lithologies of Pirambóia, Sanga-the-Cabral and Guará Geological Formations in Southern Brazil
Provedor de dados: 90
Autores: Santos,Pablo Grahl dos; Almeida,Jaime Antonio de; Sequinatto,Letícia.
ABSTRACT Quali-quantitative and crystallographic characterizations of the different minerals of a soil are essential for the best evaluation of its genesis, degree of weathering, active pedogenetic processes, physical and chemical properties, and its potential reserve of mineral nutrients. This study presents the results of mineralogical investigations carried out to verify the influence of the different lithologies of three geological formations of a sedimentary nature on the mineralogical composition of the soils and the relation of this mineralogical composition to soil chemical properties. The study area is located in the physiographic region of the Santa Maria River basin in the municipality of Rosário do Sul, RS, Brazil, at 30° 15’ 28” S and 54° 54’...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Clay mineralogy; Topolithosequence; X-ray diffractometry; Crystallographic parameters.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832017000100422