Date on Master's Thesis/Doctoral Dissertation
12-2007
Document Type
Master's Thesis
Degree Name
M.S.
Department
Chemistry
Committee Chair
Rypkema, Heather A.
Subject
Archaeological chemistry; Phosphates--Research
Abstract
Archaeologists use soil analysis to detect chemicals, like phosphate, to indicate areas of anthropogenic activity. Phosphate detection is a multi-step process, which makes standard techniques time consuming. Kinetic studies decreased the analysis time for the malachite green (MG) method of phosphate detection. The 3-minute method allows extraction and analysis to be complete in 15 minutes. Continued studies resulted in two-color spectral monitoring, which provided values instantaneously. Arsenate (As(V)) interfere with the MG method and results in overestimation of phosphate. As(V) must be reduced to non-interfering arsenite. Two As(V) reducing agents--L-Cysteine and thiosulfate--were investigated. The thiosulfate method was suitable for field implementation with the 3-minute malachite green method. L-Cysteine is compatible with both MG time scales, but pre-reduction could not be improved beyond 20 minutes. The 3-minute malachite green method was utilized at an archaeological site in Virginia. The survey led to delineation of the site boundaries.
Recommended Citation
DeNeve, Laura A., "Soil phosphate detection and archaeology : in-stride phosphate detection and the elimination of arsenate interference to the malachite green method." (2007). Electronic Theses and Dissertations. Paper 331.
https://doi.org/10.18297/etd/331
