Advanced search
Start date
Betweenand
Related content
(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Weathering rates at Alto Sorocaba basin, Brazil, using U-isotopes and major cations

Full text
Author(s):
Sardinha, D. S. [1] ; Bonotto, Daniel Marcos [1] ; da Conceicao, F. T. [1]
Total Authors: 3
Affiliation:
[1] Univ Estadual Paulista, UNESP, IGCE, BR-13506900 Sao Paulo - Brazil
Total Affiliations: 1
Document type: Journal article
Source: ENVIRONMENTAL EARTH SCIENCES; v. 61, n. 5, p. 1025-1036, SEP 2010.
Web of Science Citations: 6
Abstract

The aim of this paper was to evaluate the chemical weathering rate at Alto Sorocaba basin, So Paulo State, Brazil, as it is an important parameter on geomorphological characterization of continents. Several tools may be used for such evaluation, and this work compares the results obtained from analytical data involving the uranium concentration, the (234)U/(238)U activity ratio and the major cation concentration for samples of waters, soils, and rocks from that basin. The use of the natural uranium as a tracer in weathering rate rocks studies is advantageous since this element is virtually absent in rainwater and also allows obtaining the dissolution rocks coefficient by the (234)U/(238)U activity ratio. The Alto Sorocaba basin has serious environmental problems in terms of the quality of the rainwater and river waters, and, consequently, the geochemical balance using the main cations presented some difficulties. However, measuring of the weathering rate utilizing the U-isotopes method corresponded to 14 mu m/year that allows estimating a time of 72,000 years to weather 1 m of rock at Sorocaba River upstream from Itupararanga Reservoir, under the present climatic conditions. (AU)