『Abstract
The spatial analysis of geochemical data has several environmental
and geological applications. The present study investigated the
regional distribution of Al, Ba, Ca, Ce, Co, Cr, Cu, Fe, K, La,
Li, Mg, Mn, Na, Ni, Pb, Sc, Th, Ti, U, V, and Zn elements in stream
sediment samples from New Mexico State. These elements were studied
in order to integrate them with geological and environmental characteristics
of the area. Data are used from 27,798 samples that were originally
collected during the national uranium resource evaluation (NURE)
Hydrogeochemical and stream sediment reconnaissance (HSSR) program
in the 1970s. The original data are available as U.S.
Geological Survey Open-File Report 97-492. The study used
a variety of data processing and filtering techniques that included
univariate, bivariate, factor analyses and spatial analyses to
transform the data into a useable format. Principal component
analysis and GIS techniques are applied to classify the elements
and to identify geochemical signatures, either natural or anthropogenic.
The study found that the distribution of the investigated elements
is mainly controlled by the bed rock chemistry. For example, along
the Rio Grande rift and Jemez lineament a strong association between
Co, Cr, Cu, Fe, Ni, Sc, Ti, V and Zn was observed and indicates
that elements distribution in the area controlled by the mafic
factor. The rare earth elements (REE) factor which is consists
of Ce, La and U, also has strong, localized, clusters in the felsic
centers in New Mexico.
Keywords: Geochemical mapping; Stream sediments; Principal component
analysis; GIS; New Mexico, USA』
Introduction
Statement of the problem
Study area
Dataset
Methodology
Detection and removal of outlier
Test for normality
Data set classification
Multivarient analyses
Results
Univarient analysis
Bivariant analysis
Spatial analysis
Spatial distribution of factor scores
Median value rock chemistry for New Mexico
Discussion
Future work
Conclusions
References