Publication Date:
2024-02-02
Description:
Numerous studies use major element concentrations measured on continental margin sediments to reconstruct terrestrial climate variations. The choice and interpretation of climate proxies however differ from site to site. Here we map the concentrations of major elements (Ca, Fe, Al, Si, Ti, K) in Atlantic surface sediments (36°N-49°S) to assess the factors influencing the geochemistry of Atlantic hemipelagic sediments and the potential of elemental ratios to reconstruct different terrestrial climate regimes. High concentrations of terrigenous elements and low Ca concentrations along the African and South American margins reflect the dominance of terrigenous input in these regions. Single element concentrations and elemental ratios including Ca (e.g., Fe/Ca) are too sensitive to dilution effects (enhanced biological productivity, carbonate dissolution) to allow reliable reconstructions of terrestrial climate. Other elemental ratios reflect the composition of terrigenous material and mirror the climatic conditions within the continental catchment areas. The Atlantic distribution of Ti/Al supports its use as a proxy for eolian versus fluvial input in regions of dust deposition that are not affected by the input of mafic rock material. The spatial distributions of Al/Si and Fe/K reflect the relative input of intensively weathered material from humid regions versus slightly weathered particles from drier areas. High biogenic opal input however influences the Al/Si ratio. Fe/K is sensitive to the input of mafic material and the topography of Andean river drainage basins. Both ratios are suitable to reconstruct African and South American climatic zones characterized by different intensities of chemical weathering in well-understood environmental settings.
Keywords:
06MT41_3; 224; 230; 237; 286; 290; 293; 297; 316; 318; 321; 323; 333; 335; 368; Agadir Canyon; Aluminium; Amazon Fan; Angola Basin; Angola Benguela Front; Angola Diapir Field; Atlantic Caribbean Margin; BENEFIT/1; Brazil Basin; Calcium; Calculated; Ceara Rise; Center for Marine Environmental Sciences; Central Brazil Basin; Central South Atlantic; Congo Fan; Depth, bottom/max; DEPTH, sediment/rock; Depth, top/min; Eastern Niger fan; Elevation of event; Energy dispersive polarization X-ray fluorescence spectrometer (EDP-XRF); Event label; GeoB1412-2; GeoB1501-2; GeoB1505-4; GeoB1511-7; GeoB1512-1; GeoB1606-7; GeoB1608-9; GeoB1612-9; GeoB1703-3; GeoB1716-1; GeoB1720-3; GeoB1728-2; GeoB1808-7; GeoB2019-2; GeoB2102-1; GeoB2108-1; GeoB2112-1; GeoB2116-2; GeoB2119-2; GeoB2125-2; GeoB2208-1; GeoB2216-2; GeoB2306-1; GeoB2307-1; GeoB2709-6; GeoB2712-2; GeoB2715-1; GeoB2719-2; GeoB2723-2; GeoB2724-7; GeoB2727-1; GeoB2802-2; GeoB2806-6; GeoB2808-3; GeoB2813-1; GeoB2825-3; GeoB2906-3; GeoB2909-1; GeoB2910-2; GeoB3601-1; GeoB3605-1; GeoB3709-1; GeoB3711-1; GeoB3803-1; GeoB3804-2; GeoB3809-1; GeoB3906-9; GeoB3910-3; GeoB3911-1; GeoB3914-3; GeoB3915-1; GeoB3936-2; GeoB3939-1; GeoB4226-1; GeoB4304-1; GeoB4306-1; GeoB4310-1; GeoB4312-3; GeoB4319-11; GeoB4407-2; GeoB4409-2; GeoB4411-1; GeoB4417-5; GeoB4418-2; GeoB4420-1; GeoB4421-2; GeoB4502-6; GeoB4901-5; GeoB4903-2; GeoB4904-7; GeoB4905-2; GeoB4908-3; GeoB4911-2; GeoB4915-2; GeoB4916-3; GeoB5132-2; GeoB5201-8; GeoB5556-3; GeoB5903-2; GeoB6005-1; GeoB6105-5; GeoB6201-3; GeoB6203-1; GeoB6207-2; GeoB6210-1; GeoB6212-2; GeoB6214-4; GeoB6221-1; GeoB6230-1; GeoB6312-1; GeoB6313-2; GeoB6322-1; GeoB6340-1; GeoB6409-3; GeoB6417-2; GeoB6421-1; GeoB6427-1; GeoB6509-1; GeoB6518-2; GeoB6908-1; GeoB7001-5; GeoB7002-1; GeoB7417-1; GeoB7423-2; GeoB7430-2; GeoB8206-1; GeoB8305-1; GeoB8324-1; GeoB8329-1; GeoB8402-1; GeoB8493-2; GeoB8501-1; GeoB8505-1; GeoB8506-1; GeoB8522-3; GeoB8524-3; GeoB8626-2; GeoB8630-8; GeoB9501-4; GeoB9508-4; GeoB9512-4; GeoB9531-2; GeoB9533-3; GeoB9536-4; GeoB9538-5; GeoB9601-2; GeoB9602-2; GeoB9624-2; Giant box corer; GKG; Guayana continental slope; Guinea Basin; IOW2; Iron; Latitude of event; ln-Aluminium/Silicon ratio; ln-Iron/Calcium ratio; ln-Iron/Potassium ratio; ln-Titanium/Aluminium ratio; ln-Titanium/Calcium ratio; Longitude of event; M16/1; M16/2; M20/1; M20/2; M22/1; M23/1; M23/2; M23/3; M29/1; M29/2; M29/3; M34/1; M34/2; M34/3; M34/4; M37/1; M38/1; M38/2; M41/1; M41/3; M41/4; M42/4b; M45/1; M45/5a; M46/1; M46/2; M46/3; M46/4; M47/3; M49/3; M49/4; M56/2; M57/1; M57/2; M58/1; M58/2; M65/1; M65/2; MARUM; Mauritania Canyon; Meteor (1986); Midatlantic Ridge; Mid Atlantic Ridge; MUC; MultiCorer; Multicorer with television; Namibia continental slope; NE off San Thome; Northeast Brasilian Margin; Northern Brasil Basin; Northern Cape Basin; off Angola; off Cameroon; off Gabun; off Kunene; off northern Gabun; off Northwest Africa; off NW Africa; Petr Kottsov; POS272; Poseidon; Potassium; PROBOSWA; Santos Plateau; Sierra Leone Rise; Silicon; Slope off Argentina; SO86; Sonne; Southern Cape Basin; Titanium; TVMUC; Uruguay continental margin; Walvis Bay/Namibia; West Angola Basin; Western Equatorial Atlantic
Type:
Dataset
Format:
text/tab-separated-values, 1687 data points
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