isotopic and element characterisation of potential sources of aerosols entering the south atlantic...
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Isotopic and Element Characterisation of Potential Sources of Aerosols entering the
South Atlantic Ocean
Roulin Khondoker
The Team
Dominik Weiss, Tina van de Flierdt, Mark Rehkamper, Alex Baker, Rosie Chance
PhD Project
PhD• The Importance of Anthropogenic Vs. Natural Sources of
Aerosols into the South Atlantic Ocean (SAO)
PhD Aims• Characterise key aerosol sources in South America and Southern
Africa• Characterise aerosols collected from D357 and JC068 cruises• Make interpretations on anthropogenic vs. natural trace metal aerosol
sources in the South Atlantic Ocean
Outline of Talk
•Aims & Objectives•Materials & Methods•Results•Conclusions
Aims & ObjectivesAimsCharacterise the major ion, trace metal and REEs concentration
and isotopic ratios (of Pb, Nd and Zn) of potential sources of aerosols entering the SAO and identify characteristic sources for
the proxies
Objectives• Identify important emission regions that transport aerosols to the SAO• Collect data and samples of potential sources of these emissions• Create a database of Pb, Nd and Zn isotope data and element data of
these sources• Identify anthropogenic vs. natural sources
Types of Sources
Anthropogenic
Urban Aerosol Traffic emissionsRoad dustFuel (e.g. gasoline, coal)
Lichens
Industrial Emission Industrial plant (e.g. smelters) and factory emissionsCoal (e.g. fuel burning at power plants)
Natural
Natural Aerosol Aeolian/windblown dustDesert dustVolcanic dustLichen
Volcanic Material AshDebrisSoilVolcanic Rock
Natural Sediment Rock (e.g. rock type besides volcanic)SoilSandLoessRiverbed sediment
Sea Spray
Important Emissions
Sao Paulo & Rio de Janeiro
Patagonia
Andes
Buenos Aires
Namibia
South Africa
Anthropogenic
Urban Aerosol Traffic emissionsRoad dustFuelLichens
Industrial Emission Industrial plant and factory emissionsCoal
Natural
Natural Aerosol Aeolian/windblown dustDesert dustVolcanic dustLichen
Volcanic Material AshDebrisSoilVolcanic Rock
Natural Sediment Rock (e.g. rock type besides volcanic)SoilSandLoessRiverbed sediment
Sea Spray
Sample CollectionRegions Samples & Data were Collected from
Samples Collected
South America Type of Source Southern Africa Type of Source
Buenos AiresSao Paulo
Patagonia
Andes
Urban Aerosol
Volcanic MaterialNatural SedimentVolcanic Material
Johannesburg Urban Aerosol
Data Collected
Brazil Columbia Ecuador
Chile
Argentina
Urban Aerosol
Urban AerosolNatural SedimentVolcanic Material
Urban AerosolsNatural AerosolNatural SedimentVolcanic Material
Namibia
South Africa
Kalahari Desert
Natural AerosolVolcanic MaterialNatural Sediment
Urban aerosolIndustrial EmissionNatural Aerosol
Natural Aerosol
Sample Collection
• Collected and analysed/will analyse for : -
• Total concentration of major ions (Al, Ca, Fe, K, Mg, Na) on ICP-AES
• Total concentration of trace metals and REEs (Cu, Co, La, Mn, Nd, Ni, Pb, Sn, Zn, Y) on ICP-MS
• Pb, Nd and Zn isotopic ratios on MC-ICP-MS
• Pb & Nd data collected, but limited Zn data for Southern Africa sources (anthropogenic and natural)
• Important to collect more samples from at least Southern Africa
Source Database
Pb, Nd, Zn Isotopic Ratio DatabaseMultielement Concentration Database
Source Characterisation: Pb
Source Characterisation: Pb
Source Characterisation: Pb
Southern Africa
South America
Source Characterisation: Nd
-30 -25 -20 -15 -10 -5 0 5 10
εNd
Between Port Elizabeth to Cape Town
AndesBetween Patagonia
to B Aires
2σ
Urban Aerosol
Natural Aerosol
South America
Southern Africa
Natural Aerosol
Urban AerosolBuenos Aires
Johannesburg
Patagonia
Source Characterisation: Zn
-0.8 -0.6 -0.4 -0.2 0.0 0.2 0.4 0.6 0.8 1.0
δ66/64 ZnLyon (‰)
Igneous
Anthropogenic
Industrial Emission
Urban Aerosol
Volcanic Material
F Larner, M Rehkamper (2012) Evaluation of Stable Isotope Tracing for ZnO Nanomaterials New Constraints from High Precision Isotope Analyses and Modeling
2σ
Conclusion• Anthropogenic Vs. Natural sources between South America and
Southern Africa can be characterised using Pb isotopic ratios
• Anthropogenic sources between South America and Southern Africa can be characterised by Nd isotopic ratios
• Possibly, natural sources between South America and Southern Africa can be characterised by Nd isotopic ratios
• Zn identifies some variation between anthropogenic vs. natural sources but unable to distinguish between region of origin yet as dataset is limited
• Further work to be carried out to be able to use multielement data to characterise sources
Thank you