Noble gas loss may indicate groundwater flow across flow barriers in Southern Nevada

Publication Status is "Submitted" Or "In Press: 
LDEO Publication: 
Publication Type: 
Year of Publication: 
2003
Editor: 
Journal Title: 
Environmental Geology
Journal Date: 
Feb
Place Published: 
Tertiary Title: 
Volume: 
43
Issue: 
5
Pages: 
568-579
Section / Start page: 
Publisher: 
ISBN Number: 
0943-0105
ISSN Number: 
Edition: 
Short Title: 
Accession Number: 
ISI:000181389700010
LDEO Publication Number: 
Call Number: 
Abstract: 

Average calculated noble gas temperatures increase from 10 to 22 degreesC in groundwater from recharge to discharge areas in carbonate-rock aquifers of southern Nevada. Loss of noble gases from groundwater in these regional flow systems at flow barriers is the likely process that produces an increase in recharge noble gas temperatures. Emplacement of low permeability rock into high permeability aquifer rock and the presence of low permeability shear zones reduce aquifer thickness from thousands to tens of meters. At these flow barriers, which are more than 1,000 m lower than the average recharge altitude, noble gases exsolve from the groundwater by inclusion in gas bubbles formed near the barriers because of greatly reduced hydrostatic pressure. However, re-equilibration of noble gases in the groundwater with atmospheric air at the low-altitude spring discharge area, at the terminus of the regional flow system, cannot be ruled out. Molecular diffusion is not an important process for removing noble gases from groundwater in the carbonate-rock aquifers because concentration gradients are small.

Notes: 

652QKTimes Cited:5Cited References Count:56

DOI: 
DOI 10.1007/s00254-002-0681-1