Rock art dating
Previous tests demonstrated no decomposition of natural, fully oxidized carbonates in rock substrates at the operation level of 100 watts of RF plasma power, as illustrated in Figure 8.
The methodology is therefore applicable to limestone substrates.
Small flakes of exfoliated, blue paint were found at the site.
Optical microscopic examination determined the microstratigraphy of the samples and that the flakes were free of modern contamination.
The amount of carbon is calculated from the number of moles of carbon dioxide.
The samples were sent to the National Science Foundation-University of Arizona Accelerator Mass Spectrometry Laboratory.
A problem in archaeological dating of charcoal is that the charcoal can be "old wood." The authors conclude that "the best estimate of the age of the All American Man pictograph is the weighted average of 676 46 years BP." The antiquity of the blue paint was confirmed.
This does not preclude historic alteration of the red and white portions of the pictograph.
1990) was of paintings from the Lower Pecos region of southwest Texas only a few years after numerous Lower Pecos sites were inundated by Amistad reservoir.Two small, well conserved tabular sandstone masonry structures of Puebloan origin are in the alcove.A small storage structure may have been present, as well as an artificial floor below the pictograph. Archaeological evidence, particularly ceramics, indicates a late Pueblo II-Pueblo III site.No radioactive carbon contamination from magnesium carbonates, calcite or from gypsum derived calcium oxalate accretions on sandstone should occur at 100 watts of power.Results discussion follows the methodology presentation. The Arizona AMS sample results are presented in Table 2.Salt Creek has a significant, reliable spring with heavy flow.The authors end with the conclusion that dating techniques such as those employed in their study can be used to test hypothesis about migrations, cultural diffusion and style distribution.The following article is excerpted from a paper I submitted as part of a Biology class environmental preservation writing project.The project focus was on preservation of the American Southwest desert. Herein follows a summary of a scientific paper illustrating recent developments in rock art dating.To preserve and protect this country with its secrets, mysteries and treasures in the ancient caves and rocks is vital to understand Australia's early history.I am pleased to know that the Kimberley Foundation is researching and caring for this unique and ancient land so that future generations can appreciate the significance of our rich cultural history.