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Ground magnetic data are consistent with the interpretation that Lower Jurassic volcanic rocks of the Twin Buttes mine area (Ox Frame Volcanics) are confined to a distinct block by the northwest trending Sawmill Canyon Fault Zone which was initially active during the Lower Jurassic. Possible reactivation of the Sawmill Canyon Fault zone in the Middle Jurassic as a left-lateral wrench fault is recorded by the deposition of syntectonic red-beds (Rodolfo Formation). Lower Cretaceous rocks (Whitcomb Quartzite, Glance Conglomerate, and Angelica Akrose) were deposited in alluvial environments resulting from additional reactivation of the Sawmill Canyon Fault Zone. Upper Cretaceous (Laramide) deformation involved the formation of northwest trending folds and northwest and northeast trending reverse, tear, and later block faults during the uplift of Precambrian basement. Ore deposits of the Pima mining district are localized along a northeast trending fault zone with evidence for initial activity in the Middle Jurassic and later reactivation during the Laramide.

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One of the most visible contemporary issues in higher education is the question of academic change. In seeking a more comprehensive understanding of academic change, scholars and practioners alike have directed their attention to the causes and consequences of curricular change. The movement toward a more systematic study of academic change is most apparent in the study of four year colleges and universities but current scholarship about the decision to change academic programs and curriculum in the community college is, for the most part, speculative. Three research questions guided this study: (1) What are the sources that influence the decision to change academic programs and curriculum in the community college? (2) What are the processes that led to a decision to change academic programs and curriculum in the community college? (3) What general theory of curriculum in community colleges can be developed on the basis of the findings of the first two questions? An inductive research methodolgy was most appropriate for this study and the case study method was selected as the research procedure for a number of reasons but most importantly because it was suited to the generation of new theory for it is a methodology used to generate new theory. The focus of the study was an urban, multi-campus community college. The study examined two changes in academic policy initiated at the institution: the decision to adopt an open-entry open-exit instructional methodology for technical-occupational programs and the decision to adopt a set of uniform general education requirements for occupational and transfer programs. This case study research employed four major phases: (1) collection of the data; (2) analysis of the data; (3) presentation of the data; and (4) presentation of the findings. The research relied on three major sources of data: (1) interviews; (2) documents, and (3) field research. The analysis of the data involved the identification and categorization of relevant variables to determine emerging patterns in the data.

Interest in halocarbons has been sparked by experimental evidence suggesting that these compounds are potential carcinogens and teratogens. The U.S. EPA started a nationwide program in 1970 to identify and quantify trace organic compounds in public water supplies and sewage effluents. To date no detailed large-scale areal ground-water surveys delineating concentrations of these halocarbons have been reported in the literature at the part per trillion level and below. The objectives of this dissertation are twofold: (1) identification, quantification, and detailed areal mapping of several halocarbon species in ground water near the Santa Cruz River northwest of Tucson, Arizona; and (2) development of halocarbon techniques for age dating recently recharged (0-40 years old) ground water. The halocarbon compounds considered are: trichlorofluoromethane (CC1₃F), dichlorodifluoromethane (CC1₂F₂), carbon tetrachloride (CC1₄), chloroform (CHC1₃), trichloroethylene (C₂HC1₃), methyl chloroform (CH₃CC1₃), and tetrachloroethylene (C₂C1₄). Objective (1) includes discussions of the areal halocarbon distributions detected in the ground water, their sources, and a qualitative comparison of the distributions to ground-water quality and land use patterns adjacent to the Santa Cruz River. Objective (2) utilizes the exponential atmospheric concentration buildup of CCl₂F₂, CC1₃F, and CCl₄, and the ratios of CCl₂F₂ to CCl₃F and CCl₄ to CCl₃F. Water samples from wells and the Santa Cruz River were collected in glass syringes and brought to the laboratory for analysis. An electron-capture gas chromatograph coupled to a gas stripping/concentration unit was used to quantify the halocarbons. Four high concentration areas were delineated, each probably associated with a different source: the CWUA area which was irrigated with sewage effluent during the 1960's; Rillito Creek (near its confluence with the Santa Cruz) which is a major ground-water recharge source; the Ina Road treatment plant/landfill/oxidation ponds area; and the Roger Road treatment plant "sewer farm" which is irrigated with sewage effluent. The CCl₂F₂ to CCl₃F ratio distribution indicates that most ground water in the study area is at least partially mixed with recharge less than 30 years old. The ground water adjacent to the Rillito has an apparent age of less than 10 years, in agreement with the CCl₃F distribution. Ground water in the Cortaro area has an apparent age of about 25 years, correlating with the start of irrigation in the area.