Return to search

EVIDENCE FOR COMPARTMENTALIZATION OF AQUIFER SYSTEMS: SOLUTE AND ISOTOPE GEOCHEMISTRY OF GROUNDWATERS IN THE MIDDLE SAN PEDRO BASIN, ARIZONA

The Middle San Pedro Basin in southeastern Arizona is a typical alluvial basin in the semi-arid southwestern United States with a rapidly growing population that is dependent upon groundwater resources for water supply. This study investigated recharge areas, compartmentalization and potential mixing of water sources, and travel times of groundwater throughout the basin using variations in major ion chemistry (water type, Ca/Sr ratios, SO4/Cl ratios) and isotope ratios (18O, 2H, 3H, 34S, 13C, 14C) of groundwaters, surface waters and precipitation in conjunction with hydrogeologic data (e.g. hydraulic head and hydrostratigraphy). Recent recharge (<50 years) has occurred within mountain systems along the basin margins, and in shallow floodplain aquifers adjacent to the San Pedro River. Groundwaters in confined aquifers in the central basin were recharged at high elevation in the fractured bedrock and have been extensively modified by water-rock reactions over long timescales (up to 34,600 years). These results can be used to constrain physical assumptions of future groundwater flow models designed to help make improved water management decisions.

Identiferoai:union.ndltd.org:arizona.edu/oai:arizona.openrepository.com:10150/193440
Date January 2009
CreatorsAdkins, Candice Breanna
ContributorsMcIntosh, Jennifer C., Eastoe, Christopher J, Dickinson, Jesse E, Meixner, Thomas
PublisherThe University of Arizona.
Source SetsUniversity of Arizona
LanguageEnglish
Detected LanguageEnglish
Typetext, Electronic Thesis
RightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.

Page generated in 0.0024 seconds