Articles | Volume 15, issue 7
Nat. Hazards Earth Syst. Sci., 15, 1551–1561, 2015

Special issue: New observing strategies for monitoring natural and technological...

Nat. Hazards Earth Syst. Sci., 15, 1551–1561, 2015

Research article 17 Jul 2015

Research article | 17 Jul 2015

PM1 geochemical and mineralogical characterization using SEM-EDX to identify particle origin – Agri Valley pilot area (Basilicata, southern Italy)

S. Margiotta1,2, A. Lettino1, A. Speranza1, and V. Summa1 S. Margiotta et al.
  • 1Laboratory of Environmental and Medical Geology, CNR-IMAA, C.da S.Loja, Z.I., 85050 Tito Scalo (PZ), Italy
  • 2Osservatorio Ambientale Val d'Agri, Via Vittorio Emanuele II, 3, 85052, Marsico Nuovo, Potenza, Italy

Abstract. A PM1 geochemical and mineralogical study using Scanning Electron Microscopy (SEM) was performed on a pilot site in the Agri Valley which is close to the oil pre-treatment plant (C.O.V.A) of Europe's largest on-shore hydrocarbon reservoir. The study identified PM1 geochemical and mineralogical characters in the period before, during and immediately after a burning torch flare event. The finer fraction (DFe < 0.7 μm) consisted mainly of secondary particles and soot. In the coarser fraction (DFe ≥ 0.7 μm), natural particles originating from crustal erosion and soot were abundant. Fine quartz particles and lower Al / Si ratios are markers for desert dust origin, proving that a Saharan dust episode which occurred during the observation period played a significant role in supplying geogenic aerosol components to the PM1. Largest amounts of ≥ 0.7 μm fraction particles observed on the day of flare event may be due to a greater supply of Saharan geogenic particles. Soot had been significantly increasing long before the flare event, suggesting that this increase is also related to other causes, although we cannot exclude a contribution from flaring. S-rich aerosol consisted mainly of mixed particles originating from deposition and heterogeneous nucleation of secondary sulfates on mineral dust. Only-S particles were identified in the ≥ 0.7 μm fraction following the flare event. These particles may be indicators of larger amounts of sulphur in the atmosphere.

Final-revised paper