Mines Repository (Colorado School of Mines)
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Carving truth from the earth: integrating geophysics and Indigenous knowledge in the journey toward truth, before reconciliation
No full textIncludes bibliographical references.2024 Fall.This thesis investigates the intersecting realms of geophysics, Indigenous knowledge, and the movement for truth and reconciliation concerning the impacts of Indian Residential Schools on Indigenous peoples and tribal communities in Northern America. Through a critical examination of non-invasive geophysical practices—specifically, ground-penetrating radar (GPR), magnetometry, and frequency-domain electromagnetics (FDEM)—this work examines how these technologies contribute to the detection of unmarked graves and the restoration of cultural heritage, serving as essential tools in operationalizing truth and reconciliation efforts. This research engages with Indigenous perspectives and underscores the limitations of conventional geophysical methodologies to advocate for integrating Indigenous knowledge systems, which encompass unique understandings of land and memory, with geoscientific applications to enhance both cultural sensitivity and scientific efficacy. Informed by post-positivist, critical Indigenous theory and rooted in community collaboration, this thesis emphasizes the role of geophysics in addressing historical and ongoing harms of settler colonialism, positioning scientific inquiry as a collaborative pathway to justice and healing with Indigenous communities. By advancing culturally responsible approaches in both STEM education and geophysical applications, this research seeks to bridge geophysical practice with Indigenous ways of knowing, contributing to a framework that supports reconciliation and truth-telling efforts across North America
Iron meteorite
No full textPhotographed by Ron Wolf.Silvery grey polished surface of iron meteorite, Barringer Crater (Meteor Crater), Coconino County, Arizona
Large-scale underground mine planning including heat and ventilation considerations
No full textIncludes bibliographical references.2024 Fall.Improvement in computational power and the need for informed decision-making have increased demand for operations research in underground mining. Production schedules determine the sequence of extraction for ore and waste materials subject to production goals, resource limitations and spatial precedence. As operations progress deeper into the earth, heat accumulates and, if not accounted for, affects the health and safety of mine workers. We develop large-scale optimization models. First, we formulate a large-scale medium- and short-term production scheduling model to aid in both tactical and operational decision-making while considering transient heat effects. Second, because diesel engines account for approximately 70% of heat accumulation in the underground environment, we formulate an optimization model to determine a (near-)optimal fleet transition plan from diesel to battery vehicles. That is, we examine the trade-offs between fleet electrification, refrigeration and productivity so that mine planners can make environmentally friendlier strategic decisions. Lastly, state-of-the-art mine scheduling software tools are limited because they are not only expensive but also inflexible with respect to parametric analyses. We address these scheduling challenges by developing and implementing an integer-programming model that is adaptable to various underground mine operations. The optimization program, which we code in Python, incorporates our industry partner's objective(s) and accounts for all mine-specific constraints, resulting in realistic and operationally feasible block schedules
Enargite
No full textPhotographed by Ron Wolf.Cube-like metallic crystals of enargite, Red mountain, Ouray County, Colorado
Algorithms and subroutines for quantum optimization
No full textIncludes bibliographical references.2024 Spring.Quantum computing is a computing paradigm that leverages quantum mechanical phenomena to encode and manipulate information in ways that our current (classical) computers cannot. As of now there are only a handful of specific problems with a mathematically provable speedup over classical computing; however, there is some evidence suggesting that quantum computers could outperform classical computers in the realm of optimization. This thesis covers two quantum methods that make strides towards realizing quantum utility in the realm of optimization. The first is a quantum cooling algorithm dubbed the Relaxational Quantum Eigensolver (RQE) that uses ancillary qubits to engineer a cold bath used to remove energy and entropy from the qubits encoding our problem. By cleverly engineering this cold bath we can prepare approximate ground states in the face of depolarizing noise. Furthermore, we explore a new thermometry method that uses measurements of the thermalized ancillary qubits to characterize the optimality of our prepared states by estimating a temperature. This method will enable quantum scientists to probe and study a prepared quantum, state without directly measurement.
The second method enables an exponential speedup in Macroscopic Quantum Tunneling (MQT) which we have dubbed Symphonic Tunneling. This mechanism is new to the literature and has applications to quantum optimization, adiabatic quantum computing, and a potential realization of NISQ quantum utility.
Both methods will be valuable tools for both scientific and industrial applications of quantum optimization and simulation
Geology and hydrothermal alteration of the Red Mountain lithocap, eastern Lake City caldera, Hinsdale County, Colorado, USA
No full textIncludes bibliographical references.2024 Summer.Exploration for high-sulfidation epithermal deposits requires the development of protocols that allow distinction between mineralized and barren lithocaps. To better define the characteristics of barren lithocaps, Red Mountain, located at the western margin of the Lake City caldera in the San Juan Mountains of southwest Colorado, has been studied. This included logging of drill core, which allowed reconstruction of the distribution of lithological units and alteration styles in the subsurface. Core logging was supplemented by petrographic investigations, scanning electron microscopy, and geochemical analyses. Hyperspectral core scanning was conducted to constrain the alteration zoning within the Red Mountain lithocap.
The research demonstrates that the Red Mountain lithocap exhibits mineralogical zoning. Alteration in the shallow subsurface is dominated by quartz-alunite which grades into kaolinite with depth. In the deep part of the lithocap, smectite-white mica alteration overprints secondary biotite ± K-feldspar alteration. The smectite-white mica alteration commonly shows patchy textures. In mineralized systems, patchy pyrophyllite is a texture observed at the transition from the epithermal to the porphyry environment.
Vuggy quartz occurs as narrow ledges within the advanced argillic alteration halo. The vuggy quartz is interpreted to represent residual quartz formed through intense acid leaching of the volcanic rocks by volcanic vapors condensed into groundwater. The vugs contain small euhedral alunite crystals, but drusy quartz has not been observed at Red Mountain. The absence of widespread silicification sets the barren lithocap at Red Mountain apart from high-sulfidation epithermal deposits. In the case of these deposits, early acid-style alteration can be observed that is comparable to Red Mountain. However, the vapor-dominated magmatic-hydrothermal system changed to a liquid-dominated system prior to mineralization as the ore minerals formed from low-temperature aqueous liquids. The absence of drusy quartz may be a key indicator in exploration allowing distinction between barren and mineralized lithocaps.
Rhenium-osmium geochronology performed on two molybdenite samples yielded ages of 23.21 ± 0.14 Ma and 23.11 ± 0.10 Ma. The obtained ages are within error of the volcanic rocks formed during collapse and resurgence of the Lake City caldera suggesting that magmatic-hydrothermal activity followed immediately after the caldera volcanism
Topaz
No full textPhotographed by Ron Wolf.Glassy orange red topaz, Ouro Preto district, Minas Gerais, Brazil
Using a desire-based framework to find value in glass waste: a case study of glass cullet for rain gardens in the Caño Martín Peña
No full textIncludes bibliographical references.2024 Spring.A research study was conducted to understand the cultural, political, economic, and logistical issues that inform the current state of waste management in Puerto Rico and to evaluate a glass recycling proposal. Developed in collaboration with the ENLACE Project Corporation, this study contributes to the continuous assessment of a community-centered glass recycling initiative to support circular economic activity in the Caño Martin Peña communities. Waste management is a critical issue on the island; increased waste generation and limited space to expand waste management infrastructure, such as landfills, create a hazardous environment for the surrounding ecosystem and communities. Large-scale glass recycling efforts do not exist in Puerto Rico because there are limited end-use markets. To create contextualized solutions that address the challenges facing people in Puerto Rico when managing waste, it is important to address issues like politics and economics that inform recycling, poor social perceptions of recycling, and explore creative uses for glass cullet. This study draws on Eve Tuck’s notion of desire-based research to consider the current state of waste management in Puerto Rico and assesses a proposal to use recycled glass as a drainage medium for rain gardens. It sets both of these in the context of people’s desire to live good lives amid the challenges that impact waste management and their capacity to address these struggles. Through this approach, the study found that despite the issues that currently discourage glass recycling, there is an interest in diverting glass waste from landfills through open-loop recycling operations. The study concludes that while creative uses of glass cullet might not provide the most efficient way of putting glass waste to use, these activities are still worthwhile because they are locally appropriate and reflect a desire and motivation to find value in glass waste and increase recycling