ABSTRACT
Sediments are frequently used in forensic science for identifying contaminant sources, determining dispersion pathways, and locating areas of pollutant deposition and accumulation (Matthai and Birch 2000c). Sediments are also used to assess the magnitude of anthropogenic impacts, determine the timing of onset of contamination, and provide a history of adverse environmental change (Birch and Taylor 2002). Sediments provide this type of information by faithfully recording and time-integrating the environmental status of aquatic systems (i.e., sediments have a ‘memory’). This attribute is
Introduction ........................................................................................................ 251 Commonly Used Normalisation Techniques ................................................. 254
Physical Segregation ................................................................................. 254 Granulometric Normalisation ................................................................ 255 Elemental Normalisation ........................................................................ 256
Enrichment Factors ..................................................................... 259 Choice of Normalising Elements .............................................. 260
Postextraction Normalisation (PEN) Technique ................................. 263 Application of Normalisation Techniques ..................................................... 265
Marine Sediments from the Continental Shelf Off New South Wales Shore .................................................................................. 265
Estuarine Sediments from Port Jackson ............................................... 267 Fluvial Sediments from the Catchment ................................................ 269
Conclusions ......................................................................................................... 271 References ............................................................................................................ 272
a major advantage sediments have over other media (e.g., hydrologic, atmospheric, and biotic environments, which are spatially and temporally more variable). Being less dynamic, sedimentary systems require smaller sample sizes for meaningful interpretation (Bubb, Rudd, and Lester 1990; Birch and Taylor 2000a, 2000b) and sediment does not require such high levels of expertise to collect and analyse (compared to the water column), thus further reducing costs. Sediments are, therefore, economically attractive as a forensic tool and are being increasingly employed in environmental assessment of aquatic systems.
