REC_NOfactor; unique record identifier
DATASETfactor; abbreviated dataset group e.g. "AK+MI"
TYPEDESCfactor; abbreviated description of sample type: stream, pond, spring, soil etc
COLL_DATEinteger; sampling date
LONGITUDEnumeric; longitude in decimal degrees (NAD27 datum)
LATITIUDEnumeric; latitude in decimal degrees (NAD27 datum)
DATUMfactor; geodetic datum if different from NAD83
RELIEFfactor; relief in drainage basin from which sample was collected
FORMATIONfactor; code or name of geologic formation in which sample area was located
ROCK_TYPEfactor; rock type in area of sample collection e.g. "carbonate"
SOIL_HORIZfactor; soil horizon from which the sample was collected
COLORfactor; observed color of powdered sample during splitting
MEDIUMfactor; sample medium --- rock, sediment, standard, or unknown
SOURCEfactor; geological source of the sample medium that was collected e.g. "Beach"
AS_ICP40numeric; As (ppm) by Inductively Coupled Plasma Spectrometry (ICP) after acid dissolution
CD_ICP40numeric; Cd (ppm)
CR_ICP40numeric; Cr (ppm)
CU_ICP40numeric; Cu (ppm)
NI_ICP40numeric; Ni (ppm)
ZN_ICP40numeric; Zn (ppm)
AS_AAnumeric; As (ppm) by Hydride Atomic Absorption
HG_AAnumeric; Hg (ppm) by Hydride Atomic Absorption
PB_ICP40numeric; Pb (ppm)
C_TOTnumeric; total carbon (weight percentage) by combustion
C_ORGnumeric; organic carbon (weight percentage) as a difference between C_TOT and C_CO3
C_CO3numeric; carbonate carbon (weight percentage) by Coulometric Titration
S_TOTnumeric; total sulfur (weight percentage) by combustion