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Butte, MT, United States

Montana Tech is a university located in Butte, in the U.S. state of Montana. It was founded in 1900, originally as Montana State School of Mines with two degrees, mining engineering and electrical engineering. The "M" on the Big Butte overlooking the city stands for "Miners", and it was built in 1910. A statue of Marcus Daly stands at the entrance to Montana Tech. The statue originally stood by the Butte post office in 1906, but it was moved to Montana Tech in 1941. On January 25, 1965, the Montana School of Mines became the Montana College of Mineral Science and Technology. In 1994, Montana consolidated the university system and the school joined the University of Montana and was renamed the Montana Tech of The University of Montana.Montana Tech offers degree programs in four colleges and schools. The School of Mines and Engineering offers courses in engineering and industrial hygiene. The College of Letters science and Professional Studies offers liberal arts curricula including Technical Communication and Computer Science. The Graduate School offers post-graduate education complementary with the undergraduate programs. Highlands College offers two-year programs in occupational training and education. Total enrollment in 2009 was 2794 students, and this included 2660 undergraduate and 134 graduate students. Wikipedia.

The analytic solution of the gravity anomaly caused by a 2D irregular mass body with the density contrast varying as a polynomial function in the horizontal and vertical directions is extrapolated from a historical version in which the analytic solution for the gravity anomaly was given only at the origin of the coordinate system to any point for the density function in terms of variables relative to that origin. To calculate the gravity anomaly at stations that are not at origins, a coordinate transformation is performed, in which case the polynomial density contrast function must also be expressed in the transformed coordinates, or a transformed solution must be obtained. These analytic solutions can be obtained at any station using (1) a solution transformation method, in which the density function and boundary of a mass body are kept intact, or (2) a coordinate transformation method, in which polynomial coefficient and boundary of a mass body are transformed accordingly. The issue of singularity and instability of the analytic methods has been related to case studies. Caution should be exercised in modeling or interpreting the gravity survey data using the analytic methods for large target-distance-to-target-size ratios outside the range of numerical stability. Compared with other published methods, the analytic solution results agree very well with other numerical or seminumerical methods, indicating the solution is correct and can be applied for any gravity anomaly calculation caused by an irregular 2D mass body with the density-contrast approximated as a polynomial function of horizontal position and/or vertical position when the observation is within the range of numerical stability. © 2010 Society of Exploration Geophysicists.

The principal aim of this research is to provide a new model for investigating myopia in humans, and contribute to an understanding of the degree to which modern variation and evolutionary change in orbital and overall craniofacial morphology may help explain the common eye form association with this condition. Recent research into long and short-term evolution of the human orbit reveals a number of changes in this feature, and particularly since the Upper Paleolithic. These include a reduction in orbital depth, a decrease in anterior projection of the upper and lower orbital margins, and most notably, a reduction in orbital volume since the Holocene in East Asia. Reduced orbital volume in this geographic region could exacerbate an existing trend in recent hominin evolution toward larger eyes in smaller orbits, and may help explain the unusually high frequency of myopia in East Asian populations. The objective of the current study is to test a null hypothesis of no relationship between a ratio of orbit to eye volume and spherical equivalent refractive error (SER) in a sample of Chinese adults, and examine how relative size of the eye within the orbit relates to SER between the sexes and across the sample population.Analysis of the orbit, eye, and SER reveals a strong relationship between relative size of the eye within the orbit and the severity of myopic refractive error. An orbit/eye ratio of 3 for females and 3.5 for males (or an eye that occupies approximately 34% and 29% of the orbit, respectively), designates a clear threshold at which myopia develops, and becomes progressively worse as the eye continues to occupy a greater proportion of the orbital cavity. These results indicate that relative size of the eye within the orbit is an important factor in the development of myopia, and suggests that individuals with large eyes in small orbits lack space for adequate development of ocular tissues, leading to compression and distortion of the lithesome globe within the confines of the orbital walls. The results of this study indicate that future research examining the etiology of juvenile-onset myopia, and particularly its correlation with ancestry, sex, age, and intelligence, should consider how the eye interacts with the matrix of structural and functional components of the skull during both ontogenetic and evolutionary morphogenesis. © 2012 Elsevier Ltd.

Based on the line integral (LI) and maximum difference reduction (MDR) methods, an automated iterative forward modelling scheme (LI-MDR algorithm) is developed for the inversion of 2D bedrock topography from a gravity anomaly profile for heterogeneous sedimentary basins. The unknown basin topography can be smooth as for intracratonic basins or discontinuous as for rift and strike-slip basins. In case studies using synthetic data, the new algorithm can invert the sedimentary basins bedrock depth within a mean accuracy better than 5% when the gravity anomaly data have an accuracy of better than 0.5 mGal. The main characteristics of the inversion algorithm include: (1) the density contrast of sedimentary basins can be constant or vary horizontally and/or vertically in a very broad but a priori known manner; (2) three inputs are required: the measured gravity anomaly, accuracy level and the density contrast function, (3) the simplification that each gravity station has only one bedrock depth leads to an approach to perform rapid inversions using the forward modelling calculated by LI. The inversion process stops when the residual anomalies (the observed minus the calculated) falls within an 'error envelope' whose amplitude is the input accuracy level. The inversion algorithm offers in many cases the possibility of performing an agile 2D gravity inversion on basins with heterogeneous sediments. Both smooth and discontinuous bedrock topography with steep spatial gradients can be well recovered. Limitations include: (1) for each station position, there is only one corresponding point vertically down at the basement; and (2) the largest error in inverting bedrock topography occurs at the deepest points. © 2012 European Association of Geoscientists & Engineers.

D'Alessandro A.,Italian National Institute of Geophysics and Volcanology | Stickney M.,Montana Tech of the University of Montana
Bulletin of the Seismological Society of America | Year: 2012

In this paper we analyze the location performance of the Montana Regional Seismic Network (MRSN) using the Seismic Network Evaluation through Simulation (SNES) method. Montana has a high level of seismicity that includes approximately 1500 locatable earthquakes annually. The MRSN comprises 38 stations deployed over an area of approximately 50,000 km2. The application of the SNES method permits us to evaluate the background noise levels of the network stations and estimate an empirical law that links the variance of P and S travel-time residuals to hypocentral distance. This in turn permits us to assess the appropriateness of the velocity model used by the MRSN in the location routine. We constructed SNES maps forML 1.4, 1.6, 1.8, 2.0, and 2.2, fixing the hypocentral depth at 10 km and at the 95% confidence level. Through application of the SNES method, we show that MRSN provides the best monitoring coverage in the Flathead Valley of northwestern Montana, with errors for M L 2 that are less than 2 and 6 km for epicenter and hypocentral depth, respectively. At magnitude 2.2, this seismic network is capable of locating earthquakes as deep as 150 km and provides a threshold of completeness down to magnitude 1.5 for most of western Montana. We delineate some seismogenic areas of western Montana, including the central portion of the centennial tectonic belt in extreme southwestern Montana, that are not adequately covered by the MRSN alone.

Agency: NSF | Branch: Standard Grant | Program: | Phase: PETROLOGY AND GEOCHEMISTRY | Award Amount: 115.91K | Year: 2016

As the worlds population continues to expand and become increasingly industrialized, there will be a steady if not increasing need to discover new mineral deposits to provide the raw commodities that humans have come to depend on. In the case of gold, several decades of aggressive exploration by the mining industry in the 1970s and 1980s led to a global boom in the discovery of economically mineable gold deposits. However, the rate of discovery of new gold deposits has greatly declined in the past 10 years, partly because of a downturn in the industry, and partly because most of the deposits that are near surface and that fit conventional exploration models have already been discovered. This project will investigate the causative origins of a newly recognized class of hydrothermal gold deposits, referred to as iron oxide copper gold (IOCG) deposits, that has the potential to generate a new cycle of exploration and discovery in the metal mining industry. Despite the fact that the IOCG class includes one of the largest metal deposits in the world - Olympic Dam, Australia - there is no consensus as to how - in a geologic, geochemical, petrologic, or plate tectonic sense - these deposits form. Part of the reason for this lack of consensus is a gap in our understanding at a fundamental, thermodynamic level of how metals such as iron, gold, and copper dissolve and precipitate in high temperature hydrothermal fluids. This project will help fill in this knowledge gap by performing several sets of hydrothermal experiments under controlled laboratory conditions. This type of study will have direct benefits to the mining industry and to society in general, which demands a steady supply of these mineral commodities. As for any scientific study that generates new, high-quality thermodynamic data, the results will also be useful to scientists in other disciplines to further understand the processes that have shaped the ancient and present-day Earth.

Most researchers agree that the fluids that form IOCG deposits were hot, saline brines that were unusually oxidized: beyond this the ore deposit models diverge. This project will examine the solubility of iron oxide and gold in acidic, oxidized, saline brines at temperatures of 100 to 350 degrees C, and at oxidation states that are buffered near the aqueous ferric (Fe3+)/ferrous (Fe2+) boundary. The project will generate new thermodynamic data on the stability of aqueous ferric-, ferrous-, and gold-chloride complexes. The new data will be used to develop more accurate geochemical models for how IOCG deposits (and other types of Au-Cu-Fe deposits) form.

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