Airborne electromagnetics (EM) as a three-dimensional aquifer-mapping tool

By: , and 



The San Pedro River in southeastern Arizona hosts a major migratory bird flyway, and was declared a Riparian Conservation Area by Congress in 1988. Recharge of the adjacent Upper San Pedro Valley aquifer was thought to come primarily from the Huachuca Mountains, but the U. S. Army Garrison of Fort Huachuca and neighboring city of Sierra Vista have been tapping this aquifer for many decades, giving rise to claims that they jointly threatened the integrity of the Riparian Conservation Area. For this reason, the U. S. Army funded two airborne geophysical surveys over the Upper San Pedro Valley (see figure 1), and these have provided us valuable information on the aquifer and the complex basement structure underlying the modern San Pedro Valley. Euler deconvolution performed on the airborne magnetic data has provided a depth-to-basement map that is substantially more complex than a map obtained earlier from gravity data, as would be expected from the higher-resolution magnetic data. However, we found the output of the Euler deconvolution to have "geologic noise" in certain areas, interpreted to be post-Basin-and-Range Tertiary volcanic flows in the sedimentary column above the basement but below the ground surface.

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Additional publication details

Publication type Book
Publication Subtype Conference publication
Title Airborne electromagnetics (EM) as a three-dimensional aquifer-mapping tool
Year Published 2000
Language English
Publisher Environmental and Engineering Geophysical Society
Contributing office(s) Eastern Mineral Resources Science Center
Description HTML Document
Larger Work Title Proceedings Volume, SAGEEP-2000 Conference
Country United States
State Arizona