『Abstract
Regional patterns in ground- and surface-water chemistry of the
southern Sacramento Valley in California were evaluated using
publicly available geochemical data from the US Geological Survey's
National Water Information System (NWIS). within the boundaries
of the study area, more than 2300 ground-water analyses and more
than 20,000 surface-water analyses were available. Ground-waters
from the west side of the Sacramento Valley contain greater concentrations
of Na, Ca, Mg, B, Cl and SO4, while the east-side
ground-waters contain greater concentrations of silica and K.
These differences result from variations in surface-water chemistry
as well as from chemical reactions between water and aquifer materials.
Sediments that fill the Sacramento Valley were derived from highlands
to the west (the Coast Ranges) and east (the Sierra Nevada Mountains),
the former having an oceanic provenance and the latter continental.
These geologic differences are at least in part responsible for
the observed patterns in ground-water chemistry. Thermal springs
that are common along the west side of the Sacramento Valley appear
to have an effect on surface-water chemistry, which in turn may
affect the ground-water chemistry.』
1. Introduction
2. Methods
3. Results and discussion
3.1. Spatial patterns in ground-water chemistry
3.2. Effect of ground-water recharge on ground-water chemistry
3.3. Effects of surface-water recharge on ground-water chemistry
3.4. Evolution of ground-water chemistry and water-rock interaction
4. Conclusions
Acknowledgements
Appendix A. Supplementary material
References