In the prehispanic Andes artifacts were moved over great distances and the chemical analysis of these artifacts has shed a light on this important process at a regional scale.
The Andean Geochemistry Visualization Project provides a web-based system for visualizing archaeological chemistry and it leverages an archive of analysis results stored in an NSF-recognized web repository. This system will encourage researchers to compare their artifact chemistry with data from other projects in their region and cite these other archival datasets through a permanent web URL. Our project has succeeded in developing this system using the R statistical package and the web component R-Shiny. In its first iteration the Geochemistry Visualization system focuses on supporting the “sourcing” of obsidian archaeological artifacts. Users upload a file containing the geochemical concentrations of artifacts they have analyzed and our system will plot the new chemistry against values from a reference library of over 250 samples from throughout South America as well as provide 2 SD ellipses around chemical groups.
The reference source geochemical data from neutron activation analysis shows up along with their standard deviational ellipses.
The user can determine that artifact chemistry in the uploaded data table belong to the Chivay and the Alca obsidian sources. Our system also supports hovering with a mouse for identifying and exploring particular samples (shown here as a pink box). In addition it supports labeling of datapoints and dynamic zooming as well.
This figure shows the same data zoomed in on the lower right grouping around the Chivay source ellipse. Currently seven elements are available to plot on X and Y axes.
Additional features are needed to bolster the utility of this system. We believe we will be able to offer more plotting options, a linked dynamic table view of the chemical data, and a notes field allowing users to annotate their findings. Furthermore, there are additional datasets available for upload to the OpenContext repository to be made available as reference data in this system.