Aquifer storage characteristics of Paleozoic carbonate rocks in southeastern Nevada estimated from harmonic analysis of water-level fluctuations

The Paleozoic carbonate-rock aquifers of southeastern Nevada have significant secondary porosity due to fractures and solution cavities. Measured aquifer transmissivities are moderate to high (1.2 {dollar}times{dollar} 10{dollar}sp{lcub}-5{rcub}{dollar} to 5.3 {dollar}times{dollar} 10{dollar}sp{lcub}-1{rcub}{dollar}m{dollar}sp2{dollar}s{dollar}sp{lcub}-1{rcub}{dollar}); however, only limited information is available on the storage characteristics of these aquifers.; This paper reviews the one- and three-dimensional theories of aquifer dilatation due to earth tides, which may be used to determine storage characteristics. The three-dimensional theory includes a term to accommodate compressible grains and this concept is extended in this paper to the one-dimensional theory. Porosity is determined from specific storage and aquifer response to barometric fluctuations, and a correction for degree of confinement is applied. Aquifer matrix compressibility is determined by an iterative process from specific storage and porosity. Methods of data collection, analysis, and results are presented.; Water-level records for eleven wells and one open fault that penetrate the carbonate-rock aquifers and one well in alluvium were analyzed. Estimates of specific storage for the carbonate rock aquifers range from 1.50 {dollar}times{dollar} 10{dollar}sp{lcub}-7{rcub}{dollar} to 3.47 {dollar}times{dollar} 10{dollar}sp{lcub}-7{rcub}{dollar}m{dollar}sp{lcub}-1{rcub}{dollar} and average 2.1 {dollar}times{dollar} 10{dollar}sp{lcub}-7{rcub}{dollar}m{dollar}sp{lcub}-1{rcub}{dollar}. Storage coefficient ranges from 6.3 {dollar}times{dollar} 10{dollar}sp{lcub}-6{rcub}{dollar} to 1.21 {dollar}times{dollar} 10{dollar}sp{lcub}-4{rcub}{dollar}. Porosity ranges from 1.0 to 4.4 percent and averages 1.9 percent. Matrix compressibility ranges from 1.05 {dollar}times{dollar} 10{dollar}sp{lcub}-11{rcub}{dollar} to 1.35 {dollar}times{dollar} 10{dollar}sp{lcub}-11{rcub}{dollar}Pa{dollar}sp{lcub}-1{rcub}{dollar} and averages 1.15 {dollar}times{dollar} 10{dollar}sp{lcub}-11{rcub}{dollar}Pa{dollar}sp{lcub}-1{rcub}{dollar}.