Skip to Main Content
Book Chapter

Isotope and major-ion chemistry of groundwater in Bear Lake Valley, Utah and Idaho, with emphasis on the Bear River Range

By
Jordon Bright
Jordon Bright
Department of Geology, Box 4099, Northern Arizona University, Flagstaff, Arizona 86011, USA
Search for other works by this author on:
Published:
May 01, 2009

Major-ion chemistry, strontium isotope ratios (87Sr/86Sr), stable isotope ratios (δ18O, δ2H), and tritium were analyzed for water samples from the southern Bear Lake Valley, Utah and Idaho, to characterize the types and distribution of groundwater sources and their relation to Bear Lake’s pre-diversion chemistry. Four ground-water types were identified: (1) Ca-Mg-HCO3 water with 87Sr/86Sr values of ~0.71050 and modern tritium concentrations was found in the mountainous carbonate terrain of the Bear River Range. Magnesium (Mg) and bicarbonate (HCO3) concentrations at Swan Creek Spring are discharge dependent and result from differential carbonate bedrock dissolution within the Bear River Range. (2) Cl-rich groundwater with elevated barium and strontium concentrations and 87Sr/86Sr values between 0.71021 and 0.71322 was found in the southwestern part of the valley. This groundwater discharges at several small, fault-controlled springs along the margin of the lake and contains solutes derived from the Wasatch Formation. (3) SO4-rich groundwater with 87Sr/86Sr values of ~0.70865, and lacking detectable tritium, discharges from two springs in the northeast quadrant of the study area and along the East Bear Lake fault. (4) Ca-Mg-HCO3-SO4-Cl water with 87Sr/86Sr values of ~0.71060 and sub-modern tritium concentrations discharges from several small springs emanating from the Wasatch Formation on the Bear Lake Plateau.

The δ18O and δ2H values from springs and streams discharging in the Bear River Range fall along the Global Meteoric Water Line (GMWL), but are more negative at the southern end of the valley and at lower elevations. The δ18O and δ2H values from springs discharging on the Bear Lake Plateau plot on an evaporation line slightly below the GMWL. Stable isotope data suggest that precipitation falling in Bear Lake Valley is affected by orographic effects as storms pass over the Bear River Range, and by evaporation prior to recharging the Bear Lake Plateau aquifers.

Approximately 99% of the solutes constituting Bear Lake’s pre-diversion chemistry were derived from stream discharge and shallow groundwater sources located within the Bear River Range. Lake-marginal springs exposed during the recent low lake levels and springs and streams draining the Bear Lake Plateau did not contribute significantly to the pre-diversion chemistry of Bear Lake.

You do not currently have access to this article.

Figures & Tables

Contents

GSA Special Papers

Paleoenvironments of Bear Lake, Utah and Idaho, and its catchment

Joseph G. Rosenbaum
Joseph G. Rosenbaum
U.S. Geological Survey, Box 25046, MS 980 Federal Center, Denver, Colorado 80225, USA
Search for other works by this author on:
Darrell S. Kaufman
Darrell S. Kaufman
Department of Geology, Box 4099, Northern Arizona University, Flagstaff, Arizona 86011, USA
Search for other works by this author on:
Geological Society of America
Volume
450
ISBN print:
9780813724508
Publication date:
May 01, 2009

References

Related

Citing Books via

Related Articles
Close Modal
This Feature Is Available To Subscribers Only

Sign In or Create an Account

Close Modal
Close Modal