Plutonium, lead-210, and carbon isotopes in the Savannah estuary: riverborne versus marine sources

Plutonium isotopes as tracers for ocean processes: A review

“…Distribution and transport of particulate matter in riverine inputs to coastal waters can be estimated by using Pu isotopes in sediments contaminated with various identified sources such as global fallout and nuclear facilities linked to the river (Olsen et al, 1989;Thomas, 1997;Eyrolle et al, 2004;Miralles et al, 2004;Duffa and Renaud, 2005;Lansard et al, 2007). For example, Oktay et al (2000) found a five-fold decrease in riverine particle …”

The 7Be/210Pbxs ratio as an indicator of suspended sediment age or fraction new sediment in suspension

“…Alternatively, the decreasing 7 Be/ 210 Pb xs ratio as sediment moves through the system may be interpreted as incremental incorporation of 7 Be-dead sediment from erosional sources or from resuspension from the bottom. For example, Olsen et al (1989) calculate that more than 80 per cent of the suspended matter in the water column was resuspended bottom sediment. Applying this interpretation to the data in Table I suggests that the percentage new sediment decreases from 100 per cent in newly tagged material, to about 35-50 per cent in rivers, to 25-35 per cent in the estuary, to less than 10 per cent in the sediment traps, to 1-4 per cent on the surface of the bottom sediments.…”

Sources of land-derived runoff to a coral reef-fringed embayment identified using geochemical tracers in nearshore sediment traps

“…7c) , respectively (Cochran et al, 1990;Liu et al, 2001;Koch et al, 1996). There may have been minor contributions from surface water runoff from Hanalei watershed, but these inputs were probably a small percentage of the atmospheric flux (1 and 5%, respectively) based on work in other watersheds (Baskaran and Santschi, 1993;Olsen et al, 1989). In situ production of 210 Pb within…”

“…Pb and 7 Be concentrations are generally higher in the open ocean than at the coast because particle concentrations are lower (Bruland et al, 1974;Nozaki et al, 1976;Olsen et al, 1989). When oceanic water is advected to the coast and encounters high suspended particle concentrations, 210 Pb and 7 Be readily adsorb to particles due to their high particle affinities (Krishnaswami et al, 1973;Thomson and Turekian, 1976;Carpenter et al, 1981;Moore et al, 1981;Olsen et al, 1986;Olsen et al, 1989;Cochran et al, 1990).…”

“…When oceanic water is advected to the coast and encounters high suspended particle concentrations, 210 Pb and 7 Be readily adsorb to particles due to their high particle affinities (Krishnaswami et al, 1973;Thomson and Turekian, 1976;Carpenter et al, 1981;Moore et al, 1981;Olsen et al, 1986;Olsen et al, 1989;Cochran et al, 1990). Bottom sediment resuspension by waves and currents in shallow coastal areas results in additional 210 Pb and 7 Be scavenging onto resuspended particles (Olsen et al, 1989;Baskaran and Santschi, 1993;Jweda et al, 2008). (Feichter et al, 1991).…”