8.5.2. Technological improvements

Innovations in chemical sourcing equipment are making raw material source studies all the more important with passing years. Improvements and reduced costs for portable XRF machines will make raw material sourcing a routine part of lab work. These technologies will have a substantial impact in archaeology because many raw materials that include volcanic rocks, ceramics, ochre, and metals can be sourced, and the maintenance of spatial databases of proveniencing evidence will become a vital task in its own right.

Improvements in remote sensing technologies will probably contribute to identifying raw material sources in coming years. The reflectance properties of high silica materials like obsidian present distinctive spectral values in the thermal bands that can be isolated using techniques like spectral mixture analysis (Lillesand, et al. 2004). Furthermore, disturbed soils are often distinctive in remote sensing imagery, offering another potential venue for differentiating ancient quarries (Carr and Turner 1996). While remote sensing appears to provide a more effective way to locate obsidian sources, there are two major limitations to this approach: (1) thermal band (TIR) imagery tends to be very coarse (e.g., 90m pixels from the ASTER sensor), (2) obsidian is relatively abundant in many regions but distinguishing tool-qualityobsidian from imagery is unlikely. Such technologies can, at minimum, save time by identifying most of the major obsidian sources in a given region and then these sources can be visited individually.