Hydrologic Contributions from Springs on the Logan River, Utah
2004 Research Initiation Award Report
Investigators:
Michael Gooseff—Department of Watershed Sciences, College of Natural
Resources, Utah State University
James Evans—Department of Geology, College of Science, Utah State
University
Peter Kolesar—Department of Geology, College of Science, Utah State
University
Thomas Lachmar—Department of Geology, College of Science, Utah State
University
Summary
The Bear River Range of northern Utah, composed primarily of a thick sequence
(several km) of Paleozoic carbonates with lesser amounts of sandstone and
shale, contains at least two alpine karst aquifer systems. Higher elevations in
the range are marked by significant numbers of sinks, and members of local
National Speleological Society grottoes report a multitude of caves. Spangler
has shown that the karst is the recharge area for several of the numerous
springs issuing along the north side of the Logan River. We are investigating
the responses of two of those springs: DeWitt Spring, which is the main water
source for Logan, Utah, and which flows into the Logan River from the north,
and the spring at Spring Hollow, which enters the Logan River from the south,
within 1.5 km of DeWitt Spring. We collected samples from the Logan River, just
upstream and just downstream of the two springs, as well as from the springs,
over a year and analyzed them for water chemistry (major ions) and stable
isotopes (D, 18O, and 13C). Annual patterns of Si and Mg suggest a flushing
pattern, with reduced concentrations during snowmelt, and increased
concentrations throughout baseflow recession, at all four sampling locations.
Cl concentrations are likewise greatly depressed after the snowmelt pulse, but
afterward remain consistently low at all four sites. Stable isotope data show
that spring water is generally more enriched in D and 18O than river water,
with an enriching pattern throughout annual stream flow recession. Chemical and
flow data suggest that aquifer characteristics are different north and south of
the Logan River. Spangler's data show that the northern part of the aquifer is
a very well-developed karst drainage system, with estimated flow rates on the
order of a thousand feet per day or greater. The mean saturation index (log
(IAP/Ksp)) for calcite in water from DeWitt Spring is 0.2 and 0.1 for quartz,
slightly supersaturated, consistent with a relatively short period of
water-rock interaction. However, the mean saturation index for calcite in water
from the spring at Spring Hollow, south of the Logan River, is 1.2 and 2.0 for
quartz, an order of magnitude greater, suggesting a much slower rate of flow,
more time for water-rock interaction, and thus a less-well-developed karst
system.
Presentations resulting from this work:
- Gooseff, MN, J Evans, P Kolesar, T Lachmar, and RA Payn. 2005. Hydrologic Contributions of Springs to the Logan River, Utah. American Geophysical Union Spring Meeting, New Orleans, LA. url: http://www.agu.org/cgi-bin/wais?cc=H51C-02
- Kolesar, PT, JP Evans, MN Gooseff, TE Lachmar, and R Payn. 2005. A tale of two (or more) karsts, Bear River Range, Cache National Forest, Utah. Geological Society of America Annual Meeting, Salt Lake City, UT. url: http://gsa.confex.com/gsa/2005AM/finalprogram/abstract_96769.htm
Students supported from this work:
- Brooke Shakespeare (MS)
- Robert Payn (PhD)
- Jason Heath (MS)
Contact Information
Michael Gooseff
mgooseff‹at›mines.edu
James Evans
jpevans‹at›cc.usu.edu