Date Approved


Degree Type

Open Access Thesis

Degree Name

Master of Science (MS)

Department or School


Committee Member

Ruth Ann Armitage, Ph.D.

Committee Member

Heather Holmes, Ph.D.

Committee Member

Rosemary Brady


A black, shiny coating overlies rock paintings in Little Lost River Cave no. 1, located in southeastern Idaho. If this coating is the result of human activity within the cave – a condensate from cooking fires, for example – then a radiocarbon date on the coating would provide a minimum age for the underlying paintings. The work reported here was undertaken to test the assumption that the coating has an anthropomorphic origin. Using pyrolysis-gas chromatography-mass spectrometry (py-GC-MS) and thermally-assisted hydrolysis/methylation-GC-MS, we have compared samples of the black coating from Idaho to humic acid, a geologic material; an experimental cooking residue; and amberat from packrats. The results show that the coating is not amberat but bears the most similarity to humic acid, which would indicate a geologic origin for the coating. The age of the coating, then, is not related to the age of the paintings.

Included in

Chemistry Commons