Microchemistry of small desert varnish samples, western New South Wales, Australia

✍ Scribed by Dragovich, D.

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 64 KB
• Volume: 23
• Category: Article
• ISSN: 0360-1269
• DOI: 10.1002/(sici)1096-9837(199805)23:5<445::aid-esp859>3.0.co;2-e

✦ Synopsis

The chemistry of varnish scrapings from within and adjacent to rock engravings on sandstone outcrops in semiarid Australia was analysed using an electron microprobe (WDS mode). Small-area analyses were used to reduce potential contamination from identifiable within-varnish detrital grains and from substrate material. Ratios of (Ca + K):Ti were compared for rock engravings on older and younger rock surfaces, and between different engraving styles. Although ratios from varnish on the older surface were lower than for the younger surface, differences were not statistically significant. Sorting of analyses for potentially anomalous amounts of minor elements had little effect on the ranking of individual ratio values. Rankings of within-engraving ratio values were generally in accord with relative age expectations but differences between samples were not significant, with the chemical variability of varnish being high even without the contribution of discernible detrital inclusions.