These data were collected by the United States Geological Survey (USGS). Their description is as follows: In 2006, soil samples were collected at 960 sites (1 site per 280 square kilometers) throughout the state of Colorado. These samples were collected from a depth of 0 to 15 centimeters and, following a near-total multi-acid digestion, were analyzed for a suite of more than 40 major and trace elements. The resulting data set provides a baseline for the natural variation in soil geochemistry for Colorado and forms the basis for detecting changes in soil composition that might result from natural processes or anthropogenic activities.
Latitude and Longitude determined by hand-held GPS instrument using WGS84 datum. The longitude and latitude coordinates were converted to UTM coordinates using the following commands:
library(sp)
lonlat = co[, c("longitude", "latitude")]
coordinates(lonlat) = c("longitude", "latitude")
proj4string(lonlat) = CRS("+proj=longlat +datum=WGS84")
xy = spTransform(lonlat, CRS("+proj=utm +zone=13 ellps=WGS84"))
data(co)A data frame with 960 rows and 31 columns:
Easting (m)
Northing (m)
The latitude of the site.
The longitude of the site.
aluminum (percent)
calcium (percent)
iron (percent)
potassium (percent)
magnesium (percent)
sodium (percent)
titanium (percent)
beryllium (mg/kg)
cerium (mg/kg)
cobalt (mg/kg)
chromium (mg/kg)
copper (mg/kg)
gallium (mg/kg)
lanthanum (mg/kg)
lithium (mg/kg)
manganese (mg/kg)
molybdenum (mg/kg)
niobium (mg/kg)
rubidium (mg/kg)
scandium (mg/kg)
tin (mg/kg)
thorium (mg/kg)
thallium (mg/kg)
uranium (mg/kg)
vanadium (mg/kg)
tungsten (mg/kg)
yttrium (mg/kg)
Smith, D.B., Ellefsen, K.J., and Kilburn, J.E., 2010, Geochemical data for Colorado soils -- Results from the 2006 state-scale geochemical survey: U.S. Geological Survey, Data Series 520, 9p.