Abstracts
Submarine Groundwater Discharge (SGD) has been recognized as an important component of the ocean-continent interface. The few previous studies in Brazil have focused on nearshore areas. This paper explores SGD on the Southern Brazilian Continental Shelf using multiple lines of evidence that include radium isotopes, dissolved nutrients, and water mass observations. The results indicated that SGD may be occurring on the Continental Shelf in the Albardão region, near a paleochannel located 50 km offshore. This paleochannel may thus be a preferential pathway for the delivery of nutrient- and metal-enriched groundwater and porewater into continental shelf waters.
Porewater; Subterranean estuary; Permeable sediments
A descarga de água subterrânea ("Submarine Groundwater Discharge"; SGD) é um importante elo entre continente-oceano. No Brasil, embora haja um crescente interesse em estudos sobre este tema, eles ainda são raros e se restringem às zonas costeiras. A presente investigação explora as evidências SGD na Plataforma Continental do Sul do Brasil, as quais incluem isótopos de rádio, nutrientes dissolvidos e distribuição das massas d'água. Os resultados indicam que a SGD pode ocorrer na Plataforma Continental na região do Albardão, próximo a um paleocanal localizado a 50 km da costa. Esse paleocanal pode, assim, ser o caminho preferencial de entrada de nutrientes e de águas subterrâneas ricas em metais na plataforma continental.
Água intersticial; Estuário subterrâneo; Sedimentos permeáveis
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Publication Dates
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Publication in this collection
18 Aug 2016 -
Date of issue
Sept 2013
History
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Received
13 Sept 2010 -
Accepted
21 June 2012 -
Reviewed
27 Apr 2012