Recording a vanishing history: Three-dimensional scanning of petroglyphs at Writing-on-Stone Provincial Park, Alberta, Canada.

摘要

Three-dimensional scanning is a developing technology that has emerged over the last twenty-five years and is emerging as a growing technology for recording rock art; it provides the level of detail necessary for researchers, which is often lacking from traditional methods of recording (tracing, free-hand drawing, rubbings, and photography). Millimeter and submillimeter accuracy is obtained through three-dimensional scanning. An accurate recording of petroglyphs (also known as rock art) is necessary because additional studies are based on the recording of the petroglyph panel. Therefore, if the recording of the panel is inaccurate or lacks completeness future studies may be skewed.;The goal of this scanning project is to develop a technique for extracting petroglyph features. This technique will be applied to two known petroglyphs at Writing-on-Stone Provincial Park. Located in south-central Alberta, Canada, this park protects the largest concentration of native rock art on the Great Plains. The two panels selected for this study, DgOv-2 and DgOv-81, are located on large sandstone cliffs. The panels will be recorded with the Minolta Vivid 900 laser scanner. Once a three-dimensional model is generated utilizing software designed to process three-dimensional data (RapidForm and PolyWorks) the scans collected during the scanning process will be compared to the historic tracings to determine the level of accuracy of the model and to determine if the historic tracing may be improved upon with the discovery of additional features. Various methods of digitization, both manual and automated, will be explored. At the end of this research the goal is to have developed a technique for successful feature extraction of incised petroglyphs from the prehistoric/historic-period cultural transition of southern Alberta. This technique may then be applied to the analysis of future petroglyph documentation.