Physical Sciences and Mathematics Commons^™

Application Of The Paleomagnetic Fold Test To Determine The Relative Timing Of Sill Intrusion And Deformation In The Southwest Helena Salient, Montana, Stephen Christopher Whisner

Masters Theses

The Doherty Mountain fold complex is a highly folded and faulted region along the southern boundary of the Helena Salient in southwestern Montana. This region has a complex deformation history that is a key to deformation within the Helena Salient as a whole. A structural interpretation of the deformed rocks of this area was conducted using field mapping and cross section construction at 1:24,000 scale providing insight to the internal deformation processes involved. Fourteen folds and three major faults were mapped and analyzed showing the influence of the Southwest Montana Transverse Zone and late stage detachment faulting on fold orientation. …

A Paleoclimatic Study Of The Midwestern United States From The Stahle Isotope Records In Lake Sediments, Norman Alan Lovan

Dissertations

No abstract provided.

A Generic Multi-Electrode Automated/Semi-Automated Field Resistivity System, Douglas D. Werkema

Masters Theses

Geophysical field exploration using electrical resistivity typically employs the use of four electrodes which are progressively relocated to positions that differ from a few meters to hundreds of meters. Consequently, field operations are tiresome and often lead to imprecise locations of electrodes and poor data quality. This project develops an automated field resistivity system.

This automation of resistivity measurements is accomplished by using multiple sets of field electrodes, a programmable switch box, remotely controlling the acquisition instrument and digitally storing the results. Controlling the process is the Acquisition Control^©software, for Windows 95^© .The prototype switch box has …

Vertical Resistivity Electrode Arrays For Detecting Hydrocarbon Movement And Content In Sands, Kirt Elliott

Masters Theses

In many contamination sites where hydrocarbon is involved an accurate thickness of the contaminant can not be achieved through the most commonly used methods. The purpose of this study is to find an alternate method of determining a precise thickness and monitor the contaminant movement in conjunction with the current methods. Vertical resistivity electrode arrays were tested in a lab environment on singular probes and between probes. The arrays tested were the Wenner, dipole dipole, gradient, parallel and down-hole 3-arrays. Electrode pipes were constructed and placed into a sand tank where the hydrocarbon thickness and the water level could be …

Factors Governing The Rate Of Appearance Of Fuels In Monitoring Wells, Bradley A. Green

Masters Theses

Delays in the appearance of free product (e.g. fuels) in groundwater monitoring wells often cause costly delays in site evaluation. Little is known about how monitoring well design and installation affect this rate of appearance. This study examined the effects of well screen open area, filter pack grain size and wettability, and well development methods on the rate of appearance and subsequent thickness of free product in wells.

Laboratory and field results indicate that free product appears faster in hydrophilic filter packs than in hydrophobic filter packs. Hydrophobic filter packs with a finer grain size than the "industry standard", seem …

Sm-Nd Systematics As Indicators Of Displaced Plutons: A Test In The Idaho Batholith-Boulder Batholith Region, Christine J. Brand

Masters Theses

In east-central Idaho and western Montana a 400km-long Cretaceous and Tertiary magmatic corridor extends from the Wallowa-Seven Devils terrane to the Helena Salient. Three basement provinces underlie this area: Archean basement to the east, Permo-Triassic basement to the west, and Proterozoic basement in-between. Ideally, if Cretaceous plutons were decapitated and translated eastward along thrusts over a different basement province, then the Cretaceous pluton and the in-place Tertiary pluton would show different isotopic signatures. Pluton samples from locations evenly spaced throughout the magmatic corridor were analyzed for ε⁰_Nd, ε^t_Nd, and ¹⁴⁷Sm/¹⁴³Nd model ages …

Groundwater Hydraulics And Slope Stability Analysis: Elements For Prediction Of Shoreline Recession, William W. Montgomery

Dissertations

Studies documenting the roles that geologic materials and groundwater play in Great Lakes bluff recession are rare. This study reports findings concerning relationships between bluff lithology, bluff hydrology, and bluff recession along a 10-mile stretch of eastern Lake Michigan shoreline in heterogeneous Pleistocene deposes. According to a newly-developed, field-tested, GIS-based methodology, bluffs in the study area can be characterized lithologically as sand, clay, or mixed sand/clay, and can be characterized hydrologically as exhibiting either high head or low head.

Geotechnical analysis indicates that Atterberg limits, index properties, consolidation state, and drainage conditions affect the shear strength of bluff materials. Silty …