Evaluation Of The Ability Of Niton Portable Xrf Spectrometers To Conduct In Situ Geochemical Measurements For Correlation Of Ash Layers In The Barstow Formation, Rainbow Basin, California

Event Center A & B

Analysis of tuffs collected from Rainbow Basin were tested with a Niton portable XRF spectrometers for the purpose of determine the reliability and ability of the Niton to give precise and accurate chemical readings and to determine if the Niton could be used to make correlations of ash layers in the field. To achieve this the Tuffs were scanned in three of the Niton’s modes in three forms, one being as a powder, another as a glass disk, and third as a solid hand sample. The different samples and modes consistently had precise data with the elements Fe, K, Zn, Sr, Ca, and Rb in testing. While the elements Mn and Ti lack consistently correlation could still be made, but the usefulness of the data has yet to be determined. Of the samples scanned only the element U consistently showed no correlations. Scans in the different modes on the Niton showed some variations depending on the element. There is also a variation in the data gained form the samples in there different forms with the reported glass disk data being half of that of the soils. After this process field studies of the ash layers were conducted in situ in Rainbow basin using correction curves produced in the lab. The field data showed a wide variety in chemical composition between and along the same layers.