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The geochemical characteristics of the Paraná River suspended sediment load: an initial assessment
Author(s) -
Depetris Pedro J.,
Probst JeanLuc,
Pasquini Andrea I.,
Gaiero Diego M.
Publication year - 2003
Publication title -
hydrological processes
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.222
H-Index - 161
eISSN - 1099-1085
pISSN - 0885-6087
DOI - 10.1002/hyp.1283
Subject(s) - geology , drainage basin , sediment , hydrology (agriculture) , weathering , basalt , drainage , sedimentary rock , geochemistry , geomorphology , geography , ecology , cartography , geotechnical engineering , biology
Most water in the Paraná River drainage basin is supplied by the tropical Upper Paraná (over 60% of the total annual water discharge, 550 km 3 ). The total suspended solids (TSS) load ( c. 80 × 10 6 t year −1 ), however, is essentially furnished (50–70%) by the mountainous, arid and mostly sediment‐mantled upper Bermejo River drainage basin. This characteristic suggests that the Paraná River solid load (TSS, 600 km upstream from the mouth) is largely recycled sedimentary material, whose discharge‐weighted mean chemical index of alteration is c. 71. The extended UCC‐normalized multi‐elemental diagrams are similar to those of other world rivers. Nevertheless, the detailed inspection of UCC‐normalized rare earth element (REE) ‘spidergrams’ reveals a lithological source for the Paraná River TSS that might be compatible with either tholeiitic flood basalts (widespread in the upper drainage) or with young Andean intermediate volcanic rocks. In view of the Bermejo River's dominant role as a sediment contributor, we feel that the signature preserved in the Paraná's TSS is the latter. Conversely, the Uruguay River TSS REE signature is certainly determined by the extensive weathering products of Jurassic–Cretaceous tholeiitic basalts. Copyright © 2003 John Wiley & Sons, Ltd.