Open Access. Powered by Scholars. Published by Universities.®

Earth Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 31 - 57 of 57

Full-Text Articles in Earth Sciences

Structural Reliability Analysis Of Tunneling-Induced Ground Settlement And Damage To Adjacent Buildings: A Case Study Using Moment Methods And Flac2d, Powers Michael Apr 2017

Structural Reliability Analysis Of Tunneling-Induced Ground Settlement And Damage To Adjacent Buildings: A Case Study Using Moment Methods And Flac2d, Powers Michael

Graduate Theses & Non-Theses

Tunnels are widely used for underground space development in urban areas such as mass transit. However, tunneling in heavily congested areas is a very risky operation that can impose significant damage to adjacent buildings. In the traditional analysis of tunnel structures, the deterministic approach is commonly used. The owners or regulatory agencies establish the limiting ground surface settlement value and angular distortion value for buildings as a means of preventing tunneling-induced failure and damage to adjacent buildings. In addition, significant uncertainties in geotechnical parameters exist in the prediction of tunneling-induced ground settlement and damage to adjacent buildings. Design and analysis …


Supergene Mineralization Of The Continental Pit, Butte, Silver Bow County, Montana, Kyle Eastman Apr 2017

Supergene Mineralization Of The Continental Pit, Butte, Silver Bow County, Montana, Kyle Eastman

Graduate Theses & Non-Theses

The Butte porphyry Cu-Mo-Ag deposit has been considerably altered by supergene processes that enriched Cu and Ag, and mobilized other metals. Supergene enrichment provided early miners with excellent ore grades, and contributes significantly to current mining operations in Butte. The Continental Pit exhibits the classic leached and enriched vertical zonation that is common in near-surface porphyry systems around the world. Although studied by the Anaconda Copper Mining Company during the mid-20th century, significant and economically relevant questions remain regarding this deposit’s supergene heavy metal geochemistry and its relationship to the local hydrology and tectonic history.

This thesis investigates the paragenesis …


Several Methods To Assess Groundwater Surface-Water Interactions In Lolo Creek, Montana, Michael Chambers Oct 2016

Several Methods To Assess Groundwater Surface-Water Interactions In Lolo Creek, Montana, Michael Chambers

Graduate Theses & Non-Theses

This study addressed potential groundwater surface-water interactions along the lower reach of Lolo Creek in Lolo, Montana as part of a larger ongoing study conducted by the Montana Bureau of Mines and Geology (MBMG) Groundwater Investigation Program (GWIP). The GWIP focus is to address the causes of late summer dewatering along the lower reaches of Lolo Creek. This study’s work attempts to: (1) identify gaining/losing reaches along a 6.5 km stretch and (2) test several methods for investigating groundwater and surface-water interactions. The methods included measuring incremental streamflow, hydraulic gradients, one-dimensional temperature profiles, and collection and evaluation of radon-222. Four …


Collecting, Preparing, And Synthesizing Well Log Data For Subsurface Mapping: Example From The Bakken Formation, Asel Sherimkulova Oct 2016

Collecting, Preparing, And Synthesizing Well Log Data For Subsurface Mapping: Example From The Bakken Formation, Asel Sherimkulova

Graduate Theses & Non-Theses

Late Devonian and Early Mississippian Bakken Formation consists of three distinct members: the upper shale, middle, and lower shale. The upper and lower shales are excellent source rocks, rich in organic content. The organic material in the shales was derived from planktonic algae. Both the upper and lower shales were deposited during a transgressive event in hypoxic to anoxic conditions. The original total organic carbon content in the Bakken shales ranges from 20 to 22 weight percent, however; the content decreases to 10 to 17 weight percent as a result of maturation of hydrocarbons and primary expelling of oil. High …


Distributed Fiber-Optic Temperature Sensor Validations Using Field Deployments In The Flooded Orphan Boy Mine Shaft In Butte, Mt, Elliott Mazur Oct 2016

Distributed Fiber-Optic Temperature Sensor Validations Using Field Deployments In The Flooded Orphan Boy Mine Shaft In Butte, Mt, Elliott Mazur

Graduate Theses & Non-Theses

The process of sensor validation through experimentation with the Omnisens Distributed Temperature and Strain (DITEST) Brillouin Optical Time Domain Analyzer (BOTDA) proved to be a challenging project. The project encompassed sensor calibrations, system error minimization, sensor network design and deployment, and the characterization of temperatures in the Orphan Boy Mine shaft. Fiber-optic cable sensor calibrations yielded linear relationship coefficients 0.6-1.0MHZ/°F, indicating a strong positive correlation between Brillouin Frequency Shifts and temperature. Calibrated sensors demonstrated accuracies near ±0.8°F using the corrected error bounds from residual analyses as the benchmark. Fiber-optic measurement accuracy and repeatability were controlled by user-selected signal interrogator settings …


Determining Groundwater Sources And Ages Via Isotope Geochemistry In Big Sky, Montana, Thomson Connie Jul 2016

Determining Groundwater Sources And Ages Via Isotope Geochemistry In Big Sky, Montana, Thomson Connie

Graduate Theses & Non-Theses

The Big Sky ski resort area in southwestern Montana is experiencing exponential growth in both development and population. Concerns have arisen over the quantity of good-quality groundwater in the region, and whether there is a large enough reserve to support the growing demand. In light of already-documented water-level decreases, and domestic wells needing to be deepened or replaced, the Montana Department of Natural Resources and Conservation (DNRC) enlisted the Montana Bureau of Mines and Geology's Ground Water Investigation Program to perform an assessment of groundwater availability and quality in the region, and define groundwater supply sources.

The geology in the …


Reexamination Of Ore-Forming Processes In The Emery Mining District, Powell Co., Montana, Jarred Zimmerman Jul 2016

Reexamination Of Ore-Forming Processes In The Emery Mining District, Powell Co., Montana, Jarred Zimmerman

Graduate Theses & Non-Theses

The present investigation was undertaken in collaboration with the Montana Bureau of Mines and Geology to re-evaluate the Emery district using modern methods of ore deposit study including fluid inclusions, stable isotopes, and mineral geochemistry. Results from this thesis will be an aid in reassessing the potential of the Boulder Batholith and surrounding geologic units to host large, undiscovered precious and/or base metal deposits. The Emery (aka Zosell) district was mined from the late 1800s until the early 1950s. Mineralized quartz veins are hosted by basaltic andesite flows of the late Cretaceous Elkhorn Mountain Volcanics (EMV). Two sets of veins …


Georgetown Lake Seismic Survey, Timothy Clayton Rodriguez Apr 2016

Georgetown Lake Seismic Survey, Timothy Clayton Rodriguez

Graduate Theses & Non-Theses

A near surface seismic survey was performed in order to locate the Georgetown Thrust Fault. The location of the thrust fault relative to Georgetown Lake has been previously proposed by field mapping methods (Lonn et al.,2004). A seismic survey could be useful to identify the thrust fault because of possible geologic discontinuities at the boundaries of the thrust fault that could give rise to diffraction energy indicative of the presence of those discontinuities. The Montana Tech summer field camp recorded a seismic survey along the southern edge of Georgetown Lake. This report focuses on the optimal processing methods for near …


Paragenesis And Geochemistry Of The Calvert Tungsten Skarn Deposit, Pioneer Mountains, Montana, Joshua Messenger Apr 2016

Paragenesis And Geochemistry Of The Calvert Tungsten Skarn Deposit, Pioneer Mountains, Montana, Joshua Messenger

Graduate Theses & Non-Theses

The Calvert tungsten skarn deposit is located in the northern extent of the West Pioneer Mountains, approximately 40 miles southwest of Butte, Montana. The orebody was a significant tungsten producer from 1956-1957 and 1960-1962 during which time the mine produced a total of approximately 113,000 tons of ore averaging 1.10% WO3. The mine has a measured reserve of 128,000 tons at 1.10% WO3. The scheelite-bearing deposit occurs within skarn developed in the Pennsylvanian Amsden Formation near or in contact with a satellite pluton of the Late Cretaceous Pioneer Batholith.

Mineral paragenetic studies reveal at least three …


Processing And Interpretation Of Three-Component Vertical Seismic Profile Data, Ross Sea, Antarctica, Meltem Akan Apr 2016

Processing And Interpretation Of Three-Component Vertical Seismic Profile Data, Ross Sea, Antarctica, Meltem Akan

Graduate Theses & Non-Theses

The Antarctic Geological Drilling Program (ANDRILL) AND-2A drill hole was drilled, cored and logged in southern McMurdo Sound (SMS) in the western Ross Sea, Antarctica during the austral summer of 2007. A single near-offset, over-sea ice vertical seismic profile (VSP) was collected in the AND-2A drill hole as a part of the logging program. The source for VSP data collection was a Generator Injector (GI) air-gun which was suspended by a cable through a hole made in the sea ice. The reason for selecting a GI air gun was the minimization of the bubble pulse effects which are prevalent in …


Anaerobic Dissociation Of Thiocyanate Under Controlled Ph And Temperature, Alero Gure Apr 2016

Anaerobic Dissociation Of Thiocyanate Under Controlled Ph And Temperature, Alero Gure

Graduate Theses & Non-Theses

Thiocyanate (SCN-) is formed from both natural and industrial processes, including the use of cyanide to process gold and silver ores rich in sulfide minerals. In mining operations however, thiocyanate also plays a role as an alternative lixiviant to cyanide for leaching gold and silver out of their ores. Thiocyanate may be less toxic than cyanide but it is more stable and has proven to be more difficult to destroy in mining effluents. In addition, just like cyanide, an environmental contaminant of concern – nitrate – is the final product of the oxidation of thiocyanate.

This study investigated the chemical …


Natural Acid Rock Drainage And Ferricrete Deposit Chemistry Of The Judith Mountains, Montana, Sara Edinberg Apr 2016

Natural Acid Rock Drainage And Ferricrete Deposit Chemistry Of The Judith Mountains, Montana, Sara Edinberg

Graduate Theses & Non-Theses

The Judith Mountains are a low-elevation “island” mountain range in east-central Montana composed of a series of laccoliths and stocks cut by coarse-grained alkali granite and tinguaite dikes. The geology of the Judith Mountains in the vicinity of Red Mountain and Judith Peak, two of the tallest mountains in the range, is conducive to the creation of headwater streams that are naturally acidic. Extensive limonite staining on Red Mountain attests to the widespread presence of disseminated pyrite in hydrothermally altered porphyry rock. However, no major historical mining operations are known to the area. The acidic streams undergo neutralization in pH …


Using Naturally Occurring Radon 222 As A Tracer To Quantify Groundwater Fluxes To Streams, Mandy Machinal Apr 2016

Using Naturally Occurring Radon 222 As A Tracer To Quantify Groundwater Fluxes To Streams, Mandy Machinal

Graduate Theses & Non-Theses

Naturally occurring radon in groundwater was used to test radon mixing models. Two different mixing models were used to quantify groundwater fluxes to streams; an analytical solution and a finite difference method. Two different bodies of waters were used in this study. The first location was Johnson Creek located in Grant-Kohrs Ranch in Deer Lodge, Montana. This is a small creek where lots of sampling points were taken. The stretch of Johnson Creek where radon samples were collected was about 0.34 km long with a flowrate between 0.01 m3/s and 0.017 m3/s. The second location was Merced River located in …


Mineralogy And Environmental Geochemistry Of Slag In Lower Area One, Butte, Montana, Jenna Kaplan Apr 2016

Mineralogy And Environmental Geochemistry Of Slag In Lower Area One, Butte, Montana, Jenna Kaplan

Graduate Theses & Non-Theses

Butte, Montana is the host to a Cu-Mo porphyry deposit and has been a location of mining interest since 1864. Once copper ore is removed from this deposit it goes through a smelting process. Copper smelting processes consist of roasting, smelting, concentrating, and fire refining. During smelting, metals are separated from the waste, or gangue material. Slag is the waste material from these processes. Non-ferrous slag, such as a copper ore, removes iron and silica from the original ore. There is much interest in slag postproduction for there is often still a significant weight percent of metals trapped within a …


Cordilleran Front Range Structural Features In Northwest Montana Interpreted From Vintage Seismic 2 Reflection Data, Mason Porter Oct 2015

Cordilleran Front Range Structural Features In Northwest Montana Interpreted From Vintage Seismic 2 Reflection Data, Mason Porter

Graduate Theses & Non-Theses

Industry seismic reflection data were collected in 1983 in the Rocky Mountain Cordillera front ranges of northwest Montana. These seismic profiles represent 160 km of deep reflection data that cross the eastern Purcell anticlinorium, Rocky Mountain Trench (RMT), Rocky Mountain Basal Detachment (RMBD), and Lewis thrust. We have reprocessed these data using modern processing techniques including refraction statics, pre-stack time migration (PSTM), and pre- and post-stack depth migration. The RMT contains Tertiary fill to 1 km depth and the RMT fault system has a minimum of 3-4 km of normal displacement. The RMT and Flathead fault systems are interpreted to …


Investigation Of Ambient Seismic Noise Using Seismic Interferometry In Western Montana, Natalia Krzywosz Oct 2015

Investigation Of Ambient Seismic Noise Using Seismic Interferometry In Western Montana, Natalia Krzywosz

Graduate Theses & Non-Theses

Passive seismic interferometry is a process by which ambient noise data recorded at different seismic stations can be cross-correlated to estimate Green's functions. In the past, both surface waves and body waves have successfully been extracted by cross-correlation of ambient noise data on both regional and global scales. In this study, I have generated Matlab code to simulate an application of seismic interferometry on a synthetic model with pre-defined layers and p-wave velocities. For areas with known velocity models, the Matlab code produced in this study can be used to generate synthetic seismograms, and model the effects of cross-correlation on …


A Hydrogeophysical Investigation Of Logan, Mt Using Electrical Techniques And Seismic Refraction Tomography, Taylor Stipe Oct 2015

A Hydrogeophysical Investigation Of Logan, Mt Using Electrical Techniques And Seismic Refraction Tomography, Taylor Stipe

Graduate Theses & Non-Theses

Logan, Montana USA is located on the Gallatin River, one of the three rivers forming the headwaters of the Missouri River. Previous hydrogeological studies have determined that the location at Logan is a possible pinch-point for the local Gallatin watershed where shallow groundwater is expected to discharge into the Gallatin River. However, groundwater monitoring wells indicate dry Tertiary sediments overlying bedrock, suggesting surface and groundwater systems are disconnected. We performed shallow seismic refraction, electrical resistivity, spontaneous potential, and electromagnetic surveys to investigate the groundwater system in the study area. Geophysical measurements were obtained near the Gallatin River and close to …


Stable Isotopes Of Hydrothermal Carbonate Minerals In The Butte Porphyry-Lode Deposits, Montana, Ryan Stevenson Jul 2015

Stable Isotopes Of Hydrothermal Carbonate Minerals In The Butte Porphyry-Lode Deposits, Montana, Ryan Stevenson

Graduate Theses & Non-Theses

The stable isotopic compositions of over 90 hydrothermal carbonate minerals in the Butte porphyry-lode system were analyzed. These samples came from the underground workings as well as the active Continental Pit area. Most material came from polymetallic “Main Stage” veins which post-date the porphyry Cu-Mo mineralization of Butte. Some samples from late calcite-stellerite veins were also included in the study. Rhodochrosite d13C and d18O values range from -8.3 to -2.9‰ (average of -6.7±1.0‰) and -1.8 to 12.8‰ (average of 3.6 ±3.4‰) respectively, while calcite d13C and d18O values range from -9.0 to …


Development And Application Of A Method For Unwrapping Single Images Of Cylindrical Objects, Aaron Zosel Apr 2015

Development And Application Of A Method For Unwrapping Single Images Of Cylindrical Objects, Aaron Zosel

Graduate Theses & Non-Theses

The goal of this project was to create a software tool to unwrap digital images of cylindrical rock cores and also to create a tool to measure the accuracy of the unwrapping transform.

Measurements of an object can be taken directly from an image if the object is planar and the image plane of the camera is perpendicular to the object. If these conditions are met then picture scale allows a user to relate measurements in the image to a real world coordinate system after correcting for radial distortion. But if the object in the image is not planar or …


Rapid Analysis Of Secondary Manganese Oxides Using Portable Xrf: Applications To Environmental Geochemistry And Mineral Exploration, Dustin Jensen Apr 2015

Rapid Analysis Of Secondary Manganese Oxides Using Portable Xrf: Applications To Environmental Geochemistry And Mineral Exploration, Dustin Jensen

Graduate Theses & Non-Theses

Secondary manganese oxides (MnOx) are common weathering products of polymetallic vein deposits, and are also locally abundant in streams draining abandoned mine lands. MnOx are scavengers of trace metals, and the trace metal composition of MnOx could potentially be used as a vector to locate mineral anomalies or point sources of pollution in mining-impacted streams. This study is examining the chemistry of MnOx in weathered rock samples and partially flooded underground mine tunnels in the Butte Cu-Ag-Pb-Zn deposit, as well as MnOx crusts on boulders in small streams draining the nearby Basin-Boulder Superfund Site, Montana. Data obtained using a portable …


Shallow Groundwater Quality And Geochemistry In The Shields River Basin, South-Central Montana, Daniel D. Blythe Apr 2015

Shallow Groundwater Quality And Geochemistry In The Shields River Basin, South-Central Montana, Daniel D. Blythe

Graduate Theses & Non-Theses

Water samples were collected from 33 domestic wells, 2 springs, and 3 streams in the Shields River Basin (Basin) in southwest Montana. Samples were collected in 2013 to describe the chemical quality of groundwater in the Basin. Sampling was done to assess potential impacts to water quality from recent exploratory oil and gas drilling and to establish baseline water quality conditions. Wells were selected in areas near and away from oil and gas drilling and in areas susceptible to contamination. Water samples from surface water sites were collected in October to characterize base flow conditions. Physical characteristics of the land …


3d Block Modeling And Reserve Estimation Of A Garnet Deposit, Maurice Ayisi Apr 2015

3d Block Modeling And Reserve Estimation Of A Garnet Deposit, Maurice Ayisi

Graduate Theses & Non-Theses

The purpose of this project is to develop a three-dimensional block model for a garnet deposit in the Alder Gulch, Madison County, Montana. Garnets occur in pre-Cambrian metamorphic Red Wash gneiss and similar rocks in the vicinity. This project seeks to model the percentage of garnet in a deposit called the Section 25 deposit using the Surpac software. Data available for this work are drillhole, trench and grab sample data obtained from previous exploration of the deposit. The creation of the block model involves validating the data, creating composites of assayed garnet percentages and conducting basic statistics on composites using …


Geochemical Assessment And Separation Of Source Waters In The Upper Boulder River Watershed Near Boulder, Mt, John Anderson Apr 2015

Geochemical Assessment And Separation Of Source Waters In The Upper Boulder River Watershed Near Boulder, Mt, John Anderson

Graduate Theses & Non-Theses

Environmental samples were collected at three surface water sites between 5/21/2011 and 11/21/2014 along the Upper Boulder River near Boulder Montana. The sites were located at Bernice (within the mountain block), near the High Ore drainage (near the mountain block/basin transition), and at the USGS Gauging Station near Boulder, Montana (within the basin). The parameters measured in the field were SC, temperature, and alkalinity with occasional pH measurements. We collected samples for anions, cations, and stable isotopes in the catchment. We identified endmembers by sampling snow and groundwater and determined from available data an approximate endmember for rain, snow, and …


Temperature And Pressure Sensing In Three Flooded Underground Mine Workings In Butte, Montana, Usa, Tyler Hagan Apr 2015

Temperature And Pressure Sensing In Three Flooded Underground Mine Workings In Butte, Montana, Usa, Tyler Hagan

Graduate Theses & Non-Theses

Temperature and pressure were measured in several flooded underground mine shafts in order to assess the potential for the development of additional mine-based geothermal heating in Butte, Montana, USA. Temperature was sensed using both optical fibers, functioning as a distributed sensor, and thermistors, functioning as point sensors; while pressure was sensed using a piezoresistive strain gauge. Upon observing good agreement between the continuous and discrete temperature sensors, we found no significant change in temperature with increasing depth within the water column. This suggests the thorough transfer of heat throughout the mine shaft via convection. Moreover, we found water temperature (T) …


Biogeochemical Cycling In A Headwater Stream And Riparian Zone, A. Capri Gillam Apr 2015

Biogeochemical Cycling In A Headwater Stream And Riparian Zone, A. Capri Gillam

Graduate Theses & Non-Theses

Several teams of researchers at multiple universities are currently measuring annual and seasonal fluxes of carbon dioxide and other greenhouses gases (nitrous oxide and methane) in riparian wetlands and upland forests in the Tenderfoot Creek Experimental Forest (TCEF), a subalpine watershed in the Little Belt Mountains, Montana. In the current thesis, the author characterized the geochemistry and stable carbon isotope composition of shallow groundwater, soil water, and stream water in upper Stringer Creek, near sites that are being investigated for gas chemistry and microbial studies. It was hypothesized that if methanogenesis were a dominant process in the riparian wetlands of …


Geochemistry And Stable Isotopes Of Surface Water And Groundwater In The Continental Pit In Butte, Montana, Usa, Amber Mcgivern Jul 2014

Geochemistry And Stable Isotopes Of Surface Water And Groundwater In The Continental Pit In Butte, Montana, Usa, Amber Mcgivern

Graduate Theses & Non-Theses

The Continental porphyry Cu‐Mo mine, located 2 km east of the famous Berkeley Pit lake of Butte, Montana, contains two small lakes that vary in size depending on mining activity. In contrast to the acidic Berkeley Pit lake, the Continental Pit waters have near-neutral pH and relatively low metal concentrations. The main reason is geological: whereas the Berkeley Pit mined highly‐altered granite rich in pyrite with no neutralizing potential, the Continental Pit is mining weakly‐altered granite with lower pyrite concentrations and up to 1‐2% hydrothermal calcite. The purpose of this study was to gather and interpret information that bears on …


Subsurface To Surface Correlation Of The Tensleep Sandstone In The West Flank Of The Pryor Mountains In Carbon County, Montana, William B. Rhyne May 2014

Subsurface To Surface Correlation Of The Tensleep Sandstone In The West Flank Of The Pryor Mountains In Carbon County, Montana, William B. Rhyne

Graduate Theses & Non-Theses

The Pennsylvanian Tensleep Sandstone is an eolian and nearshore marine/sabka quartz arenite unit with prominent outcrops along the western Pryor/Bighorn Mountain front east of Red Lodge, MT. Regionally, the formation represents one of the largest ergs in the global geologic record. High permeability makes it an important oil and gas reservoir and aquifer in south central Montana and throughout much of Wyoming. The Tensleep Sandstone’s high percentage of quartz content and grain roundness, due to its eolian origin, makes it a prospective source for natural proppant sand.

Three continuous 4-inch cores were obtained during a cooperative project between Montana Tech …