par Fagel, Nathalie;Allan, Mohammed;Le Roux, Gaël 
;Mattielli, Nadine ;Piotrowska, Natalia;Sikorski, Jarek
Référence Geochimica et cosmochimica acta
Publication Publié, 2014-03-29
;Mattielli, Nadine ;Piotrowska, Natalia;Sikorski, JarekRéférence Geochimica et cosmochimica acta
Publication Publié, 2014-03-29
Article révisé par les pairs
| Résumé : | A high-resolution peat record from Eastern Belgium reveals the chronology of dust deposition for the last 2500. years. REE and lithogenic elements in addition to Nd and Pb isotopes were measured in a 173. cm age-dated peat profile and provide a continuous chronology of dust source and intensity. Calculated dust flux show pronounced increases c. 300. BC, 600. AD, 1000. AD, 1200. AD and from 1700. AD, corresponding to local and regional human activities combined with climate change.The Industrial Revolution samples (1700-1950. AD) are characterised by a significant enrichment in Sc-normalised REE abundance (sum REE/Sc. >. 25) due to intensive coal combustion. For the pre-Industrial Revolution samples, the Sc-normalised REE abundance (10. <. Sum REE/Sc. <. 25) and the εNd variability (-13 to -9) are interpreted by a mixing between dust particles from local soils and long-range transport of desert particles. Three periods characterised by dominant-distal sources (c. 320. AD, 1000. AD and 1700. AD) are consistent with local wetter-than-average intervals as indicated by a lower degree of peat humification. Local erosion prevails during the drier (higher humification) intervals (100. AD, 600. AD). On a global scale, more distal supplies are driven during colder periods, in particular during the Oort and Maunder minima, suggesting a potential link between dust deposition and global climate. Combining REE abundance, fractionation between Light REE and Heavy REE and Nd isotope data in ombrotrophic peat allows one to distinguish between dust flux changes related to human and climate forcings. © 2014 Elsevier Ltd. |
