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Fig. 5 | Journal of Palaeogeography

Fig. 5

From: Reply to discussions by Zavala (2019) and by Van Loon, Hüeneke, and Mulder (2019) on Shanmugam, G. (2018, Journal of Palaeogeography, 7 (3): 197–238): ‘the hyperpycnite problem’

Fig. 5

Rio de la Plata Estuary. a Location of the Rio de la Plata Estuary (white circle). Image credit: ETOPO1 Global Relief Model, C. Amante and B.W. Eakins, ETOPO1 Arc-Minute Global Relief Model: Procedures, Data Sources and Analysis, NOAA Technical Memorandum NESDIS NGDC-24, March 2009. with additional labels by G. Shanmugam; b Satellite image showing the Rio de la Plata Estuary. This image is used as an index map to provide a regional perspective. Image courtesy Jacques Descloitres, MODIS Land Group, NASA GSFC. Image acquired on April 24, 2000; c Satellite image showing the Rio de la Plata Estuary with hyperpycnal plumes that tend to move towards the Argentinian shelf to the south. Framiňan and Brown (1996) used the term “turbidity front” for this hyperpycnal plume. Note that the entire, 220-km wide, plume gets diluted and dissipated with an irregular front, which fails to advance into the South Atlantic. This dilution of plume is attributed to external controls, such as ocean currents operating on the shelf. The Paraná River, the second longest river in South America after the Amazon, supplies three-quarters of the fresh water that enters the estuary, with the remainder arriving from the Uruguay River. Image credit: NASA Earth Observatory, NASA image by Jeff Schmaltz, LANCE/EOSDIS MODIS Rapid Response. Image acquired on March 31, 2012. Fossati et al. 2014 and Fossati and Piedra-Cueva 2013

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