Enviromagnetic, major element, and grain-size analyses of surface sediment samples along the continental margin between East Brazil and Patagonia

Autoria(s): Razik, Sebastian; Govin, Aline; Chiessi, Cristiano Mazur; von Dobeneck, Tilo
Cobertura

MEDIAN LATITUDE: -34.142058 * MEDIAN LONGITUDE: -50.334348 * SOUTH-BOUND LATITUDE: -47.441667 * WEST-BOUND LONGITUDE: -60.091667 * NORTH-BOUND LATITUDE: -20.820000 * EAST-BOUND LONGITUDE: -39.856667 * DATE/TIME START: 1993-03-01T00:00:00 * DATE/TIME END: 2009-06-23T16:16:00
Data(s)

04/03/2015
Resumo

Continental margin sediments of SE South America originate from various terrestrial sources, each conveying specific magnetic and element signatures. Here, we aim to identify the sources and transport characteristics of shelf and slope sediments deposited between East Brazil and Patagonia (20°-48°S) using enviromagnetic, major element, and grain-size data. A set of five source-indicative parameters (i.e., chi-fd%, ARM/IRM, S0.3T, SIRM/Fe and Fe/K) of 25 surface samples (16-1805 m water depth) was analyzed by fuzzy c-means clustering and non-linear mapping to depict and unmix sediment-province characteristics. This multivariate approach yields three regionally coherent sediment provinces with petrologically and climatically distinct source regions. The southernmost province is entirely restricted to the slope off the Argentinean Pampas and has been identified as relict Andean-sourced sands with coarse unaltered magnetite. The direct transport to the slope was enabled by Rio Colorado and Rio Negro meltwaters during glacial and deglacial phases of low sea level. The adjacent shelf province consists of coastal loessoidal sands (highest hematite and goethite proportions) delivered from the Argentinean Pampas by wave erosion and westerly winds. The northernmost province includes the Plata mudbelt and Rio Grande Cone. It contains tropically weathered clayey silts from the La Plata Drainage Basin with pronounced proportions of fine magnetite, which were distributed up to ~24° S by the Brazilian Coastal Current and admixed to coarser relict sediments of Pampean loessoidal origin. Grain-size analyses of all samples showed that sediment fractionation during transport and deposition had little impact on magnetic and element source characteristics. This study corroborates the high potential of the chosen approach to access sediment origin in regions with contrasting sediment sources, complex transport dynamics, and large grain-size variability.
Formato

application/zip, 5 datasets
Identificador

https://doi.pangaea.de/10.1594/PANGAEA.843560

doi:10.1594/PANGAEA.843560
Idioma(s)

en
Publicador

PANGAEA
Relação

(Figure 2) Parameter frequency distributions (URI: http://store.pangaea.de/Publications/Razik_etal_2015/Figure2_Parameter_frequency_distributions.txt) (txt format)

(Table 3) Cluster result robustness (URI: http://store.pangaea.de/Publications/Razik_etal_2015/Table3_Cluster_result_robustness.pdf) (pdf format)

(Table 4) Cluster center properties (URI: http://store.pangaea.de/Publications/Razik_etal_2015/Table4_Cluster_center_properties.pdf) (pdf format)

(Table 5) Euclidean distances between cluster centers (URI: http://store.pangaea.de/Publications/Razik_etal_2015/Table5_Euclidean_distances_between_cluster_centers.pdf) (pdf format)
Direitos

CC-BY: Creative Commons Attribution 3.0 Unported

Access constraints: unrestricted
Fonte

Supplement to: Razik, Sebastian; Govin, Aline; Chiessi, Cristiano Mazur; von Dobeneck, Tilo (2015): Depositional provinces, dispersal, and origin of terrigenous sediments along the SE South American continental margin. Marine Geology, 363, 261-272, doi:10.1016/j.margeo.2015.03.001
Palavras-Chave #0.1T terrigenous; 0.3T; 0.3T terrigenous; 0.412-0.375 µm; 0.452-0.412 µm; 0.496-0.452 µm; 0.545-0.496 µm; 0.598-0.545 µm; 0.656-0.598 µm; 0.721-0.656 µm; 0.791-0.721 µm; 0.868-0.791 µm; 0.948-1.041 mm; 0.953-0.868 µm; 1.041-1.143 mm; 1.047-0.953 µm; 1.143-1.255 mm; 1.149-1.047 µm; 1.255-1.377 mm; 1.261-1.149 µm; 1.377-1.512 mm; 1.384 -1.261 µm; 1.512-1.66 mm; 1.520-1.384 µm; 1.668-1.520 µm; 1.822-1.660 mm; 1.832-1.668 µm; 10.78-9.818 µm; 101.1-92.09 µm; 11.83-10.78 µm; 111.0-101.1 µm; 12.99-11.83 µm; 121.8-111.0 µm; 133.7-121.8 µm; 14.26-12.99 µm; 146.8-133.7 µm; 15.65-14.26 µm; 161.2-146.8 µm; 17.18-15.65 µm; 176.8-161.2 µm; 18.86-17.18 µm; 194.2-176.8 µm; 2.010-1.832 µm; 2.207-2.010 µm; 2.423-2.207 µm; 2.660-2.423 µm; 2.6T terrigenous; 2.920-2.660 µm; 20.70-18.86 µm; 2000-1822 µm; 213.2-194.2 µm; 213.2-234.1 µm; 22.73-20.70 µm; 234.1-256.8 µm; 24.95-22.73 µm; 256.8-282.1 µm; 27.38-24.95 µm; 282.1-309.6 µm; 3.205-2.920 µm; 3.519-3.205 µm; 3.862-3.519 µm; 30.07-27.38 µm; 309.6-339.8 µm; 33.01-30.07 µm; 339.8-373.1 µm; 36.24-33.01 µm; 373.1-409.6 µm; 39.77-36.24 µm; 4.240-3.863 µm; 4.655-4.240 µm; 409.6-449.7 µm; 43.67-39.78 µm; 449.7-493.6 µm; 47.94-43.67 µm; 493.6-541.9 µm; 5.110-4.655 µm; 5.610-5.110 µm; 52.62-47.94 µm; 541.9-594.9 µm; 57.77-52.62 µm; 594.9-653 µm; 6.158-5.611 µm; 6.761-6.158 µm; 63.41-57.77 µm; 653.0-716.9 µm; 69.62-63.41 µm; 7.421-6.760 µm; 716.9-786.9 µm; 76.42-69.61 µm; 786.9-863.9 µm; 8.147-7.421 µm; 8.943-8.147 µm; 83.89-76.42 µm; 863.9-948.2 µm; 9.818-8.943 µm; 92.09-83.90 µm; ARM, Intensity, per unit mass; ARM/IRM; ARM0.1T / IRM0.1T; Bartington MS2B bulk sensor; Beckman Coulter Laser diffraction particle size analyzer LS 200; Center for Marine Environmental Sciences; chi_terrig; Cluster; cluster membership; Cluster membership; Cluster type; Comment; D50; Depth; DEPTH, sediment/rock; Energy dispersive polarization X-ray fluorescence spectrometer (EDP-XRF); Event; Fe; Fe/K; fuzzy c-means cluster analysis; Grain size [µm] 0.39; Grain size [µm] 0.43; Grain size [µm] 0.47; Grain size [µm] 0.52; Grain size [µm] 0.57; Grain size [µm] 0.63; Grain size [µm] 0.69; Grain size [µm] 0.76; Grain size [µm] 0.83; Grain size [µm] 0.91; Grain size [µm] 1; Grain size [µm] 1.1; Grain size [µm] 1.2; Grain size [µm] 1.32; Grain size [µm] 1.45; Grain size [µm] 1.59; Grain size [µm] 1.75; Grain size [µm] 1.92; Grain size [µm] 10.29; Grain size [µm] 105.93; Grain size [µm] 1090.81; Grain size [µm] 11.29; Grain size [µm] 116.27; Grain size [µm] 1197.69; Grain size [µm] 12.4; Grain size [µm] 127.61; Grain size [µm] 13.61; Grain size [µm] 1314.59; Grain size [µm] 14.94; Grain size [µm] 140.1; Grain size [µm] 1442.92; Grain size [µm] 153.83; Grain size [µm] 1584.27; Grain size [µm] 16.4; Grain size [µm] 168.87; Grain size [µm] 1739.11; Grain size [µm] 18; Grain size [µm] 185.35; Grain size [µm] 19.76; Grain size [µm] 1908.93; Grain size [µm] 2.11; Grain size [µm] 2.31; Grain size [µm] 2.54; Grain size [µm] 2.79; Grain size [µm] 203.48; Grain size [µm] 21.7; Grain size [µm] 223.36; Grain size [µm] 23.81; Grain size [µm] 245.18; Grain size [µm] 26.14; Grain size [µm] 269.21; Grain size [µm] 28.7; Grain size [µm] 295.53; Grain size [µm] 3.06; Grain size [µm] 3.36; Grain size [µm] 3.69; Grain size [µm] 31.51; Grain size [µm] 324.4; Grain size [µm] 34.59; Grain size [µm] 356.11; Grain size [µm] 37.97; Grain size [µm] 390.92; Grain size [µm] 4.05; Grain size [µm] 4.44; Grain size [µm] 4.88; Grain size [µm] 41.68; Grain size [µm] 429.18; Grain size [µm] 45.76; Grain size [µm] 471.14; Grain size [µm] 5.35; Grain size [µm] 5.88; Grain size [µm] 50.23; Grain size [µm] 517.19; Grain size [µm] 55.13; Grain size [µm] 567.73; Grain size [µm] 6.45; Grain size [µm] 60.52; Grain size [µm] 623.22; Grain size [µm] 66.44; Grain size [µm] 684.16; Grain size [µm] 7.08; Grain size [µm] 7.78; Grain size [µm] 72.94; Grain size [µm] 751.03; Grain size [µm] 8.54; Grain size [µm] 80.07; Grain size [µm] 824.5; Grain size [µm] 87.89; Grain size [µm] 9.37; Grain size [µm] 905.12; Grain size [µm] 96.49; Grain size [µm] 993.57; Inten (ARM); Inten (IRM); IRM, Intensity, per unit mass; Iron; Iron/Potassium ratio; Iteration; K; kappa_fd; Magnetometer, cryogenic, pass-through, 2G Enterprises 755 R; MARUM; Median, grain size; Membership to cluster 1; Membership to cluster 2; Membership to cluster 3; NLM; NLMx; NLMy; Non-linear mapping; Non-Linear mapping; Potassium; Sammons err; Sammons error; Saturation isothermal remanent magnetization/iron ratio; SIRM/Fe; SIRM2.6T / Fe; Size fraction 0.412-0.375 µm; Size fraction 0.452-0.412 µm; Size fraction 0.496-0.452 µm; Size fraction 0.545-0.496 µm; Size fraction 0.598-0.545 µm; Size fraction 0.656-0.598 µm; Size fraction 0.721-0.656 µm; Size fraction 0.791-0.721 µm; Size fraction 0.868-0.791 µm; Size fraction 0.948-1.041 mm; Size fraction 0.953-0.868 µm; Size fraction 1.041-1.143 mm; Size fraction 1.047-0.953 µm; Size fraction 1.143-1.255 mm; Size fraction 1.149-1.047 µm; Size fraction 1.255-1.377 mm; Size fraction 1.261-1.149 µm; Size fraction 1.377-1.512 mm; Size fraction 1.384 -1.261 µm; Size fraction 1.512-1.660 mm; Size fraction 1.520-1.384 µm; Size fraction 1.668-1.520 µm; Size fraction 1.822-1.660 mm; Size fraction 1.832-1.668 µm; Size fraction 10.78-9.818 µm; Size fraction 101.1-92.09 µm; Size fraction 11.83-10.78 µm; Size fraction 111.0-101.1 µm; Size fraction 12.99-11.83 µm; Size fraction 121.8-111.0 µm; Size fraction 133.7-121.8 µm; Size fraction 14.26-12.99 µm; Size fraction 146.8-133.7 µm; Size fraction 15.65-14.26 µm; Size fraction 161.2-146.8 µm; Size fraction 17.18-15.65 µm; Size fraction 176.8-161.2 µm; Size fraction 18.86-17.18 µm; Size fraction 194.2-176.8 µm; Size fraction 2.000-1.822 mm; Size fraction 2.010-1.832 µm; Size fraction 2.207-2.010 µm; Size fraction 2.423-2.207 µm; Size fraction 2.660-2.423 µm; Size fraction 2.920-2.660 µm; Size fraction 20.70-18.86 µm; Size fraction 213.2-194.2 µm; Size fraction 213.2-234.1 µm; Size fraction 22.73-20.70 µm; Size fraction 234.1-256.8 µm; Size fraction 24.95-22.73 µm; Size fraction 256.8-282.1 µm; Size fraction 27.38-24.95 µm; Size fraction 282.1-309.6 µm; Size fraction 3.205-2.920 µm; Size fraction 3.519-3.205 µm; Size fraction 3.862-3.519 µm; Size fraction 30.07-27.38 µm; Size fraction 309.6-339.8 µm; Size fraction 33.01-30.07 µm; Size fraction 339.8-373.1 µm; Size fraction 36.24-33.01 µm; Size fraction 373.1-409.6 µm; Size fraction 39.77-36.24 µm; Size fraction 4.240-3.863 µm; Size fraction 4.655-4.240 µm; Size fraction 409.6-449.7 µm; Size fraction 43.67-39.78 µm; Size fraction 449.7-493.6 µm; Size fraction 47.94-43.67 µm; Size fraction 493.6-541.9 µm; Size fraction 5.110-4.655 µm; Size fraction 5.610-5.110 µm; Size fraction 52.62-47.94 µm; Size fraction 541.9-594.9 µm; Size fraction 57.77-52.62 µm; Size fraction 594.9-653.0 µm; Size fraction 6.158-5.611 µm; Size fraction 6.761-6.158 µm; Size fraction 63.41-57.77 µm; Size fraction 653.0-716.9 µm; Size fraction 69.62-63.41 µm; Size fraction 7.421-6.760 µm; Size fraction 716.9-786.9 µm; Size fraction 76.42-69.61 µm; Size fraction 786.9-863.9 µm; Size fraction 8.147-7.421 µm; Size fraction 8.943-8.147 µm; Size fraction 83.89-76.42 µm; Size fraction 863.9-948.2 µm; Size fraction 9.818-8.943 µm; Size fraction 92.09-83.90 µm; S-r; S-ratio (Hematite/Magnetite); stress of mapping; Susceptibility, frequency dependence; Susceptibility, specific, terrigenic; terrigenous
Tipo

Dataset
Acesso ao item digital