Quantitative colour analysis of beach and dune sediments for forensic applications: A Portuguese example

• Type: Article in International Scientific Journal
• Date: 2009

Authors

Alexandra Guedes (Author) FCUP; Helena Ribeiro (Author) FCUP; Bruno Valentim (Author) FCUP; Fernando Noronha (Author) FCUP

Journal

Title: Forensic Science International

Vol. 190

Pages: 42-51

ISSN: 0379-0738

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 20 Citations

Scopus - 26 Citations

Scientific classification

FOS: Medical and Health sciences > Other medical sciences

Other information

Authenticus ID: P-003-FTK

DOI: 10.1016/j.forsciint.2009.05.010

Abstract (EN): In this study, the colour of 23 sediment samples collected in different Portuguese beaches in the North (Entre-Douro and Minho) and 33 in the South (Algarve) was tested. Spectral colour parameters (L*a*b*) were measured after several presentation/pre-treatment methods: drying at 40 degrees C, sieving (<150 and <63 mu m) and ashing at 850 degrees C, using a Konica Minolta CM-2600d spectrophotometer. A descriptive statistical analysis with L*a*b* values for each presentation/pre-treatment method was performed to ascertain within-sample reproducibility followed by a hierarchical cluster analysis to obtain significant discrimination between samples using colour analysis. The samples analysed presented a colour closest to red and yellow continuums and a lightness close to the pale side of the L*a*b* system colour sphere with samples collected in the North presenting analysis on average darker L values than the samples collected in the South. The cluster analysis, dried, unsieved bulk samples L*a*b* values gave the best discrimination between samples. The clusters analysis dried, unsieved bulk samples-dried, sieved <150 mu m fraction set allowed better discrimination between samples compared with the dried, sieved <63 mu m fraction set or dried, unsieved bulk samples-ashed bulk, unsieved samples set and even with dried, unsieved bulk samples/dried, sieved <150 mu m fraction/dried, sieved <63 mu m fraction/ashed bulk, unsieved samples considered all together.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10