The Mercedes Au-Ag District, Sonora, Mexico: Geology, Geochemistry and Structure of a Sierra Madre Low-sulfidation Epithermal System

The Mercedes district contains a series of Oligocene-aged low-sulfidation quartz-carbonate veins with economic Au and Ag mineralization. The veins are hosted in dextral-normal faults contained within andesitic flows, flow breccias and lahar deposits within the Sierra Madre Occidental volcanic sequence. These are localized within two structural basins adjacent to a northwest-trending anticline that exposes pre-mineral tuffs and sedimentary units. The vein mineralogy is characterized by a unique ferruginous green quartz and Mn-oxide bearing calcite assemblage along with both primary and supergene Au-Ag mineralization. Three vein systems within the district were studied: the Mercedes, Klondike and Lupita/Diluvio systems. The Mercedes vein contains the highest grades within the district, is highly-brecciated and displays weak and anomalous geochemical zonation patterns attributed to a high degree of hydrothermal and tectonic brecciation and permeability controlled supergene remobilization. The vein possesses a 4-phase paragenesis. Phase I was the major mineralizing phase, introducing native Au as well as unidentified silver minerals (likely both electrum and silver sulfosalts) along with green quartz and pyrite. Phase II began during a hydrothermal/tectonic brecciation event and appears as a dark Mn-oxide bearing calcite and rhodochrosite cement between phase I breccias. Phase III was a later quartz and calcite veinlet event with local amounts of dark carbonate. Phase IV was the final event, and is a post-mineral oxidation event creating hematite after pyrite, limonite, zeolites and cerargyrite. Statistical evaluation of the geochemical data reveals that Au and Ag grades are poorly correlated with one another, due to post-mineral reworking of the silver mineralogy. Au is most strongly correlated with Pb, Cu, Hg, Zn and Se in that order. Ag is somewhat correlated with Se and Hg, with only weak (<0.5) correlations with other elements. Ca is positively correlated with only C and Mn, supporting the fact that the dark carbonate phase is a Mn-oxide/calcite intergrowth. This is interpretation is further supported by XRF analysis of the carbonates and the presence of boxworks of pyrolusite and other Mn-oxides in former carbonate sites leached by acidic groundwaters. The Klondike vein displays a similar mineralogy and paragenesis to the Mercedes vein, but retains a higher degree of structural order that results in a less-permeable system displaying a stronger and more apparent classical geochemical zonation. Geochemical correlations display a similar pattern to Mercedes with Pb, Cu and Hg being the most correlative elemental indicators of Au grade. Ag correlations with these elements are somewhat higher than in Mercedes. The Lupita/Diluvio system is hosted within a listric structure and consists of the fault-hosted Lupita vein and the overlying Diluvio stockwork, hosted within a gravitationally-displaced block of a quartz-lithic tuff that had been structurally prepared for mineralization during its displacement along the Lupita structure. The Lupita/Diluvio system displays a similar mineralogy and paragenesis to the Mercedes and Klondike vein systems. From these data, a number of inferences can be made. First is that the high degree of brecciation and transport within the Mercedes vein has destroyed the classical epithermal geochemical zonation that is somewhat present in the Klondike system and better defined in the Lupita/Diluvio system. This "washing-out" was accomplished through both physical transport and overprinting during multiple hydrothermal pulses. Second, supergene remobilization related to meteoric fluids has altered the grades and distribution of precious metals as well as further modified the geochemical zonation. The presence of cerargyrite and mineralogical evidence suggests that these processes may be related to the poor Ag recoveries (~30%) and erratic Au/Ag ratios within the vein systems. Third, it is apparent that the structural weaknesses that localized the mineralization on the property reflect the regional structural fabric of both dextral and extensional tectonics

The relation of food to the advancement of civilization

Citation: Burtner, Nellie. The relation of food to the advancement of civilization. Senior thesis, Kansas State Agricultural College, 1900.Morse Department of Special CollectionsIntroduction: This is an age of industrial and political reform just as truly as the period of The Reformation and the French Revolution, though unaccompanied with the inhumanity and carnage which attended these upheavals. The Caucasian race is far in advance of the barbarous methods of progress. In the future the reforms will be brought about gradually, and the word reform will lose its terror and be changed to a word meaning simply advancement only. Science is quietly revolutionizing the world by exploding many of the old theories which have stood for decades. The search for truth is growing more and more zealous and extensive. It is revealing more and more of the fundamental principles of life, and the extensive studies in Physiology and Psychology are permitting a keen insight into the laws governing the mental and moral habits of man. Not satisfied still, he has penetrated the bowels of the earth, and explored the mysteries of the heavens with the gigantic telescope. The chief end of all this research is to benefit and uplift man. Experience long has taught us that all races are not alike susceptible to learning, nor is it confined to any one. Caucasian race includes the most civilized people in the world, and it occupies the most desirable portions of the globe. This people is characterized by its industry morality and brain energy. Their history has been one of progress and triumph, which is manifested in many ways, viz. intellect, mode of living, surroundings, food, social and political relations, and morality. To treat these fully, would require many volumes or to treat any one accurately would fill a large book. In the following one will confine ourselves to the discussion of the food of a nation in regard to its degree of civilization

Texture characterization in DIRSIG

This research project tested the quality of DIRSIG\u27s texture characterization routines for a grass target and potential techniques to improve it. The objective of the DIRSIG is to produce output images that are analogous to real image outputs so the model can be applied to a wide range of problems. It is very important that both spectral and spatial properties of targets are modeled correctly to obtain realistic results. DIRSIG applies texture to each pixel spectrally. Current techniques examine only one bandpass region, using statistical means to compare a texture image in that bandpass with a spectral database in order to determine which curve will be used for a particular pixel. The research in this project examined the quality of this procedure, and several potential methods for improvement. DIRSIG images were generated to simulate two different scenes for which real images exist. ENVI’s principle components analysis utility was than used to quantify the information in each image for comparison. Modifications were than made to the process to expand the spectral database, and incorporate a new algorithm into DIRSIG that examines multiple bandpass regions when determining which spectra to use for a pixel. The output for each of these new scenarios was than tested for comparison with DIRSIG’s previous results, and the results obtained for the truth images. This research has quantitatively examined the ability of DIRSIG to replicate real world texture characteristics, specifically for a grass target. Research discovered a large gap between the amount of information that is contained in images of real world data and those simulated by DIRSIG. Expanding the spectral database did produce a slight increase in results, increasing the qualitative appearance of the image as well. The amount of data contained in the DIRSIG image remained significantly less than that contained in the real image. Increasing the number of bandpasses employed by DIRSIG in determining which spectra to map onto a particular pixel, results indicated two different concepts. Adding one band increased the ability of DIRSIG to map correctly choose the spectra. Additional bandpasses may increase the quality of an image, however, choosing too many bandpass regions for an image can cause the resulting quality of the image to decrease. The process is very complex, the output quality is dependent on the particular imaging system that is being modeled, the bandpasses that are chosen, and the amount of bandpasses that are used as references

Determinants and mechanisms of smoking cessation: secondary outcomes analyses of a community smoking intervention in Boston public housing

Cigarette smoking is the leading cause of preventable morbidity and mortality in the United States. While smoking rates have steadily declined among the general population, smoking is becoming increasingly concentrated among socioeconomically disadvantaged groups due to higher initiation and lower cessation rates. This dissertation examines determinants and mechanisms of smoking cessation in the context of the Kick it for Good study (KIG), a community smoking intervention for Boston public housing residents. In the first study, we explored mediators and moderators of the KIG intervention effect on smoking cessation. We did not find any significant mediators for 3-mo cessation outcomes, although there was modest evidence for mediation by self-efficacy to quit at 12-months. We found living with other smokers and perceived stress were moderators of the KIG intervention effect on smoking cessation. In the second study, we examined predictors of attitudes and knowledge of nicotine replacement therapy (aNRT). We found discussing smoking cessation with a healthcare provider and use of nicotine replacement therapy (NRT) were associated with more positive attitudes and greater knowledge of NRT. The KIG intervention did not impact aNRT outcomes throughout the study period. In the third study, we examined the effect of depression on smoking cessation and whether this effect was moderated by social support. We found smokers with depression classified by the 10-item Center for Epidemiologic Studies Depression Scale (CES-D-10) were more likely to report smoking abstinence than those without depression. Social support did not moderate the effect of depression on cessation. We also conducted a sensitivity analysis to determine if the cutoff of 10 for the CES-D was valid in this population of low-income and racially/ethnically diverse smokers. We did not find evidence of depression misclassification by the CES-D-10, although there remains the need to validate the scale in socioeconomically disadvantaged populations. These findings provide valuable information on how smokers living in Boston public housing were able to achieve smoking abstinence in the context of a cessation intervention. The insights gained from these results may be applied to future intervention studies to help address the disparity in smoking rates among socioeconomically disadvantaged smokers

Maude Truxal Burtner Scrapbook

Maude Zetta Burtner, née Truxal (1882-1962) was a graduate of Otterbein University in 1907. The daughter of Reverend J. P. and Sarah Truxal, she was born in Pennsylvania before coming to Westerville. After graduation she married Elmer E. Burtner in 1910, a minister for the United Brethren Church in Westerville. After his death in 1923, she became an elementary school teacher, and was the principal of the Longfellow School when she retired. She had two children, Edwin and Margaret. This scrapbook was her creation in 1907 and contains photographs and names of many Otterbein students and includes the playbill and cast photo from the first theatrical production at Otterbein, “As You Like It,” of which Maude was a cast member. Images included within the scrapbook: buildings from campus; portraits of students; portraits of Bishop Mills and Dr. S. Lotwell of Columbia University; cast photos including one of Maude in character as Rosalind, Daughter to the Banished Duke; a program for “As You Like It” performed in June of 1907 by the senior class of Otterbein University; Fifty-First Commencement documents; and a Sixtieth Anniversary program.https://digitalcommons.otterbein.edu/maude_burtner/1000/thumbnail.jp

The Influence of Carbon Subsidies on Stream Chemistry and Function in Northern Michigan Streams

Headwater streams are largely allochthonous, relying on subsidies to fuel productivity. Carbon inputs are important to streams not only because they fuel productivity but they also strongly affect many instream biological processes and physiochemical characteristics. Terrestrial ecosystems contribute a large component of carbon to streams which varies in quantity and quality, possibly affecting instream carbon concentrations and the biological uptake of that carbon. In addition, tributaries of the Great Lakes provide a unique opportunity to examine carbon sources and sinks more frequently associated with marine environments. For example, potomodromous fish which migrate between the Great Lakes and its tributaries to spawn may deliver a pulse of lake derived nutrients similar to the well-documented pulse of ocean-derived nutrients associated with anadromous fish moving between the ocean and rivers. The goal of this study was to examine linkages between these allochthonous carbon inputs and steam functioning in a remote largely undeveloped temperate forest. Terrestrial inputs were evaluated by examining dissolved organic carbon (DOC) concentration in 26 streams, and comparing them against riparian and watershed land cover. At the riparian level, forest (p<0.001), agriculture (p<0.001) and wetlands (p<0.001) all significantly influenced instream DOC concentrations. However, at the watershed level, only agriculture explained a significant amount of variation in DOC (p<0.001). Watershed land cover was also compared to carbon spiraling turnover length although no significant effects were detected. Fish derived inputs were evaluated via an evaluation of nutrient influences associated with the spawning migrations of longnose and white sucker in the Salmon Trout River. In total, 1,474 suckers were recorded swimming upstream in 2008. Whole stream metabolism was measured before and after the run, upstream and downstream of a barrier that prevented fish passage to distinguish between the effect of fish-derived carbon and possible temporal effects. Although not found to be significant, there was an obvious spike in metabolism at the downstream site during the run, which may indicate an effect of the sucker runs. The findings suggest that these two sources of allochthonous carbon are important to stream functioning and anthropogenic alterations of these inputs have the potential to affect the aquatic carbon cycle.Master of ScienceNatural Resources and EnvironmentUniversity of Michiganhttp://deepblue.lib.umich.edu/bitstream/2027.42/64481/1/Burtner 2009.pd