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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Controls of heavy minerals and grain size in a holocene regressive barrier (Ilha Comprida, southeastern Brazil)

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Author(s):
Guedes, C. C. F. [1] ; Giannini, P. C. F. [1] ; Nascimento, Jr., D. R. [1] ; Sawakuchi, A. O. [1] ; Tanaka, A. P. B. [1] ; Rossi, M. G. [1]
Total Authors: 6
Affiliation:
[1] Univ Sao Paulo, Inst Geociencias, Dept Geol Sedimentar & Ambiental, BR-05508080 Sao Paulo - Brazil
Total Affiliations: 1
Document type: Journal article
Source: Journal of South American Earth Sciences; v. 31, n. 1, p. 110-123, FEB 2011.
Web of Science Citations: 15
Abstract

Ilha Comprida is a regressive barrier island located in southeastern Brazil that was formed essentially by Quaternary sandy sediments. Ilha Comprida sediments were analyzed to assess heavy mineral indices and grain size variables. The spatial variation of heavy minerals and grain size was interpreted in terms of the present barrier dynamics and the barrier's evolution since the Middle Holocene. These analyses allowed for the identification of the main factors and processes that control the variation of heavy minerals and grain size on the barrier. Rutile and zircon (RZi) and tourmaline and hornblende (THi) are significantly sensitive to provenance and exhibit the contributions of the Ribeira de Iguape River sediments, which reach the coast next to the northeastern end of Ilha Comprida. In addition to the influence of provenance, TZi responds mainly to hydraulic sorting processes. This agrees with a sediment transport pattern characterized by a divergence of two resultant net alongshore drifts southwest of the barrier. The sediments from the Ribeira de Iguape River reach the barrier directly through the river mouth and indirectly after temporary storage in the inner shelf. The combination of grain size and heavy mineral analyses is a reliable method for determining sediment transport patterns and provenance. (C) 2010 Elsevier Ltd. All rights reserved. (AU)

FAPESP's process: 07/51511-4 - Quaternary sedimentary evolution of Ilha Comprida, São Paulo state
Grantee:Carlos Conforti Ferreira Guedes
Support type: Scholarships in Brazil - Master