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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

The effects of mineral reactions on trace metal characteristics of groundwater in desert basins of southern Arizona

Marozas, Dianne Catherine January 1987 (has links)
The geochemistry, of groundwater collected from deep wells in the western section of the lower Santa Cruz basin of southeastern Arizona, was studied in order to determine the extent to which geochemica] analysis can be used to assess fluid flow and major and trace element migration patterns along hydrologic flowpaths in desert basins. Interaction between groundwater and enclosing sediments, and mixing between chemically distinct basin groundwater is found to exert a significant control on the chemical patterns that have evolved in the system. Activity-activity diagrams of the Na-Si-O-H system show that groundwater throughout the basin clusters near the three phase boundary between fluid, kaolinite, and montmorillonite and trends along the boundary to higher log (aNa⁺/aH⁺) values. A reaction model generated with computer program PHREEQE, that combines silicate weathering, kaolinite-Na-beidellite equilibrium, calcite equilibrium, and solution mixing, can simulate trends in groundwater composition along flowpaths in the basin. Trace metals introduced into the basin by the weathering of a buried porphyry copper deposit become spatially separated upon migration. Metal concentrations are found to be correlated to major cation concentrations. Cu is associated with high Na concentrations and a high ratio of Carbonate:Ca, whereas Zn is associated with high Ca concentration and a low ratio of Carbonate:Ca. Behavior of Cu and Zn during low-temperature transport can be controlled by the effects of mineral alteration on groundwater composition. Computer analysis of early basin diagenesis shows that changes in major solute composition that accompany weathering, constrained by equilibrium with clays and calcite, can produce the metal segregation pattern observed in the basin. Because the aquifer is strongly influenced by silicate and carbonate mineral equilibrium, the introduction of Central Arizona Project recharge, which is not in equilibrium with alluvial minerals, into the basin, requires a response by mineral reactions that attempt to restore the system to a state of equilibrium with kaolinite, montmorillonite, and calcite. A reaction model is developed to predict the consequent effects of outside recharge on groundwater quality.
32

Geothermometry, geochemistry, and alteration at the San Manuel porphyry copper ore-body, San Manuel, Arizona

Davis, Jerry Dean, 1944- January 1974 (has links)
No description available.
33

Alternative management strategies for a farm utilizing a solar powered irrigation system

Lierman, Wally Kent January 1979 (has links)
No description available.
34

An Economic Survey of Pinal County Agriculture

University of Arizona.; Agricultural Extension Service. 04 1900 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
35

A study of subsidence due to mining by block caving, San Manuel Mine, Pinal County, Arizona

McLehaney, James Dewey, 1928- January 1958 (has links)
No description available.
36

Geology of the Copper Hill area, Winkelman, Arizona

Evensen, James Millard, 1931- January 1961 (has links)
No description available.
37

THE PHYSICAL, CHEMICAL, AND SPECTRAL CHARACTERISTICS OF SOILS AT PAGE RANCH INTERNATIONAL CENTER, PINAL COUNTY, ARIZONA.

Ghenniwa, Abdelgiawad Mohamed. January 1985 (has links)
No description available.
38

A geochemical-petrological study of mid-tertiary volcanism in parts of Pima and Pinal Counties, Arizona

Eastwood, Raymond Lester, 1940- January 1970 (has links)
No description available.
39

Sulphide zoning at the Lakeshore copper deposit, Pinal County, Arizona

South, David Long, 1948- January 1972 (has links)
No description available.
40

FACTORS AFFECTING ATTEMPTS TO ESTABLISH COUNTY-WIDE JUNIOR COLLEGES IN SPARSELY POPULATED REGIONS

Snider, Richard Harlan, 1921- January 1969 (has links)
No description available.

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