Documentation for data sets

Chemical composition of obsidian sources

Usage

ObsidianSources

Format

A data frame with 113 rows and 7 variables:

Code

A one-character variable with source code: A, B, C, D, E, F

ID

A character variable with an artificial lab ID; the first character is the value of Code; the remaining characters are 1:n, with n samples from a source

Rb

The rubidium value

Sr

The strontium value

Y

The ytterbium value

Zr

The zirconium value

Nb

The niobium value

Source

Data are from Steve Shackley's website http://www.swxrflab.net/ and from files provided by Shackley.

Details

A data set containing data on five elements from 113 obsidian samples from five sources in the Jemez caldera in north central New Mexico. The element presence values (parts per million) were obtained using x-ray fluorescence at a laboratory at the University of California in Berkeley.