Magnetic fingerprint of the late Holocene inception of the Río de la Plata plume onto the southeast Brazilian shelf

A Multi‐Proxy Approach to Unravel Late Pleistocene Sediment Flux and Bottom Water Conditions in the Western South Atlantic Ocean

“…Magnetic characterization of modern Plata River sediments identified the presence of ultrafine and fine (4-16 µm) detrital magnetite in the Plata mud belt, that would be transported up to 24°S by the BCC (Razik et al, 2015). The influence of Plata River sediments at this latitude was also suggested for the mid-Holocene based on environmagnetic parameters (Mathias et al, 2014). In addition, the elemental composition of suspended sediment from the Plata River exhibits the same Al/Si values as measured in sediments from the south Brazilian margin (24°S) (Depetris et al, 2003).…”

“…According to Gaiero et al (2003), about 90% of the present day material deposited in the SW South Atlantic is delivered by the atmospheric pathway and comes from Patagonia. The magnetic characterization of sediments from the southeastern Brazil margin (24°S) indicates the Argentinean loess as the possible source of fine magnetite (PSD) between 6 and 4.7 ka BP (Mathias et al, 2014). In addition to the Plata Plume sediment, Razik et al (2015) suggested that material delivered to the Southern Atlantic margin from the Argentinean Pampas by westerly winds is transported further north (24°S) as well.…”

Tracing the origin of reservoir sediments using magnetic properties in Southeastern Brazil

“…In Brazil, magnetic sediment fingerprinting has been successfully applied to investigate environmental processes, indicating the potential for the technique to improve soil and sediment erosion control. In addition, magnetic mineralogy fingerprinting was applied in Southern Brazil and detected a shift in sediment delivery at the estuary of the Paraná River from distinct sources of sediments, from fine-grained magnetite to coarsegrained hematite derived from basalt (Mathias, Nagai, Trindade, & Mahiques, 2014). Moreover, magnetic susceptibility was also successfully used as a predictor of erodibility factors in the modeling process for large tropical areas (Barbosa et al, 2019).…”

Radiogenic isotopic and clay mineralogical signatures of terrigenous particles as water-mass tracers: New insights into South Atlantic deep circulation during the last termination

“…Consequently, direct aeolian inputs cannot be significant at our site, and oceanic currents appear to be the main contributors to sedimentation (Moriarty, 1977;Petschick et al, 1996;Kuhn and Diekmann, 2002). This means that any aeolian particles from Patagonia delivered to the southwest Atlantic (Mathias et al, 2014) The clay-size fraction (i.e., the < 2 µm particles) with very high specific surface readily floats and hence can undergo long-range transportation (>500 km). Consequently, particles within this grain-size fraction can be used to record the relative contribution of the main deep-water masses.…”

“…On the other hand, Patagonia and Pampas are dry and windy areas (Clapperton, 1993). Consequently, part of the detrital particles is exported to the ocean via aeolian processes as loess (Mathias et al, 2014 (Bremner and Willis, 1993;Petschick et al, 1996;Bayon et al, 2015; figure 1).…”