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Field Test Of A Calcite Dissolution Rate Law: Fort’S Funnel Cave, Mammoth Cave National Park, J. Scott Slunder Dec 1993

Field Test Of A Calcite Dissolution Rate Law: Fort’S Funnel Cave, Mammoth Cave National Park, J. Scott Slunder

Masters Theses & Specialist Projects

The laboratory-derived calcite dissolution rate law of Plummer et al. (1978) is the most widely used and mechanistically detailed expression currently available for predicting dissolution rates as a function of water chemistry. Such rate expressions are of great use in understanding timescales associated with limestone karst development. Little work has gone into the field testing of the rate law under natural conditions.

This work compared measured dissolution rates measured by a crystal weight loss experiment in Buffalo Creek within Fort’s Funnel Cave, which lies within a pristine, forested catchment of Mammoth Cave National Park. Continuous water chemistry sampling over the …


Changes In Benthic Invertebrate Composition In Response To Reservoir Aging, Arthur Popp Dec 1993

Changes In Benthic Invertebrate Composition In Response To Reservoir Aging, Arthur Popp

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.


Spectral Analysis Of The Flow Behavior Of Big Spring, Kings Canyon National Park, California, Linda Urzendowski Dec 1993

Spectral Analysis Of The Flow Behavior Of Big Spring, Kings Canyon National Park, California, Linda Urzendowski

UNLV Theses, Dissertations, Professional Papers, and Capstones

Big Spring, the resurgence of a karst aquifer in the Lilburn Cave system (Kings Canyon National Park, California), displays the uncommon phenomena of ebb and flow discharge during periods of high runoff.

Hydrograph analyses indicate that the portion of Lilburn Cave between the Z-Room and Big Spring is primarily a conduit flow aquifer. The power spectra strongly indicate a nonlinear system, with evidence of quasi-linear behavior found on a smaller scale. The transfer and kernel function indicate that no additional significant inputs or outputs to the system exist. The bench-scale model built to simulate the ebb and flow cycles in …


Strategic Minerals In The New World Order, Kent H. Butts Nov 1993

Strategic Minerals In The New World Order, Kent H. Butts

Books, Monographs & Collaborative Studies

The author discusses U.S. dependence on overseas sources of strategic minerals essential to sustain its economy and defense sector. U.S. vulnerability to a loss of access to important mineral supplies is more pronounced now than at any time since World War II. The uneven distribution of strategic mineral reserves and their concentration in a handful of politically unstable countries make it essential that U.S. policymakers ensure mineral availability in the new world order. The author considers the geographical imbalance of mineral trade patterns, evaluates the stability of the major strategic mineral producing countries, and assesses the potential for mineral supply …


An Integrated Surface And Borehole Seismic Case Study: Fort St. John Graben Area, Alberta, Canada, Ronald C. Hinds, Richard Kuzmiski, Neil Lennart Anderson, Barry R. Richards Nov 1993

An Integrated Surface And Borehole Seismic Case Study: Fort St. John Graben Area, Alberta, Canada, Ronald C. Hinds, Richard Kuzmiski, Neil Lennart Anderson, Barry R. Richards

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The deltaic sandstones of the basal Kiskatinaw Formation (Stoddard Group, upper Mississippian) were preferentially deposited within structural lows in a regime characterized by faulting and structural subsidence. In the Fort St. John Graben area, northwest Alberta, Canada, these sandstone facies can form reservoirs where they are laterally sealed against the flanks of upthrown fault blocks. Exploration for basal Kiskatinaw reservoirs generally entails the acquisition and interpretation of surface seismic data prior to drilling. These data are used to map the grabens in which these sandstones were deposited, and the horst blocks which act as lateral seals. Subsequent to drilling, vertical …


An Integrated Surface Seismic/Seismic Profile Case Study: Simonette Area, Alberta, Ronald C. Hinds, Neil Lennart Anderson, Richard Kuzmiski Nov 1993

An Integrated Surface Seismic/Seismic Profile Case Study: Simonette Area, Alberta, Ronald C. Hinds, Neil Lennart Anderson, Richard Kuzmiski

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

On the basis of conventional surface seismic data, the 13-15-63-25W5M exploratory well was drilled into a low-relief Leduc Formation reef (Devonian Wood-bend Group) in the Simonette area, west-central Alberta, Canada. The well was expected to intersect the crest of the reef and encounter about 50-60 m of pay; unfortunately it was drilled into a flank position and abandoned. The decision to abandon the well, as opposed to whipstocking in the direction of the reef crest, was made after the acquisition and interpretive processing of both near-and far-offset (252 and 524 m, respectively) vertical seismic profile (VSP) data, and after the …


Earth News, Fall 1993, Department Of Earth Science, University Of Northern Iowa. Oct 1993

Earth News, Fall 1993, Department Of Earth Science, University Of Northern Iowa.

Earth News

Inside this issue:

--- Year in Review
--- Staff News
--- Earth Science Seminar Series, Spring Semester, 1993
--- Graduates - 1993
--- Earth Science Fall 1993 Seminar Schedule
--- Sigma Gamma Epsilon
--- News from Alumni
--- Seasons Greetings from the Department of Earth Science


Epa's Map Of Radon Zones Nebraska, U.S. Environmental Protection Agency's, U.S. Geological Survey Sep 1993

Epa's Map Of Radon Zones Nebraska, U.S. Environmental Protection Agency's, U.S. Geological Survey

United States Environmental Protection Agency: Publications

Sections 301 and 309 of the 1988 Indoor Radon Abatement Act (IRAA) direct EPA to identify areas of the United States that have the potential to produce elevated levels of radon. EPA, the U.S. Geological Survey (USGS), and the Association of. American State Geologists (AASG) have worked closely over the past several years to produce a series of maps and documents which address these directives. The EPA Map of Radon Zones is a compilation of that work and fulfills the requirements of sections 307 and 309 of IRAA. The Map of Radon" Zones identifies, on a county-by-county basis, areas' of …


Epa's Map Of Radon Zones, Nebraska, Sharon W. White, Lisa Ratcliff, Kirk Maconaughey, R. Thomas Peake, Dave Rowson, Steve Page, Linda C. S. Gundersen, R. Randall Schumann, James K. Otton, Doug Owen, Russell Dubiel, Kendell Dickinson, Sandra L. Szarzi Sep 1993

Epa's Map Of Radon Zones, Nebraska, Sharon W. White, Lisa Ratcliff, Kirk Maconaughey, R. Thomas Peake, Dave Rowson, Steve Page, Linda C. S. Gundersen, R. Randall Schumann, James K. Otton, Doug Owen, Russell Dubiel, Kendell Dickinson, Sandra L. Szarzi

United States Environmental Protection Agency: Publications

Sections 307 and 309 of the 1988 Indoor Radon Abatement Act (IRAA) direct EPA to identify areas of the United States that have the potential to produce elevated levels of radon. EPA, the U.S. Geological Survey (USGS), and the Association of, American State Geologists (AASG) have worked closely over the past several years to produce a series of maps and documents which address these directives. The EPA Map of Radon Zones is a compilation of that work and fulfills the requirements of sections 307 and 309 of IRAA. The Map of Radon Zones identifies, on a county-by-county basis, areas of …


An Overview Of Some Of The Large Scale Mechanisms Of Salt Dissolution In Western Canada, Neil Lennart Anderson, Ralph W. Knapp Sep 1993

An Overview Of Some Of The Large Scale Mechanisms Of Salt Dissolution In Western Canada, Neil Lennart Anderson, Ralph W. Knapp

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Well log and seismic data indicate that the bedded rock salts of the Devonian Prairie Formation were widely distributed and uniformly deposited in the Lloydminster area, Western Canada; however, as a result of extensive leaching, the distribution of these salts is not now what it once was. The Lloydminster area is now bisected by the north-south trending main dissolutional edge of the Prairie salt. Thick salt (up to 150 m) is preserved to the west of this edge; to the east the salt is mostly absent. The paper presents an overview of the envisioned principal mechanisms of salt dissolution. The …


Groundwater Velocity In An Unconfined Aquifer With Rectangular Areal Recharge, Vitaly A. Zlotnik, Glenn Ledder Aug 1993

Groundwater Velocity In An Unconfined Aquifer With Rectangular Areal Recharge, Vitaly A. Zlotnik, Glenn Ledder

Department of Earth and Atmospheric Sciences: Faculty Publications

Three-dimensionsal solutions for the hydraulic head and velocity components for transient groundwater flow in an unconfined compressible aquifer of finite thickness with a rectangular areal recharge source are analyzed using a linearized mathematical model. The solution generalizes Dagan's (1967) results, which were obtained for an idealized aquifer of infinite thickness, and Hantush's (1967) results, which were derived using the Dupuit assumptions. Hydraulic head and velocity components are estimated by asymptotic methods for large times, which are most appropriate for contaminant transport problems. Numerical analysis of the solution demonstrates spatial features of the velocity components in general and a transient effect …


Three-Dimensional Transport Simulations Of The Dispersal Of Volcanic Aerosol From Mount Pinatubo, T. Duncan A. Fairlie Jul 1993

Three-Dimensional Transport Simulations Of The Dispersal Of Volcanic Aerosol From Mount Pinatubo, T. Duncan A. Fairlie

Mechanical & Aerospace Engineering Theses & Dissertations

A global finite-difference model that simulates the large-scale dynamics of the Earth's stratosphere and mesosphere is combined with a global spectral transport model to investigate aspects of the initial dispersal of the volcanic aerosol plume from the Mount Pinatubo eruption in 1991. Results of the modelling study are found to compare well with observations of the volcanic plume made from satellite instruments. Dynamical quantities, diagnosed from the simulated fields are used to provide insight into the evolution of the volcanic plume. Lagrangian trajectory analysis is used to help assess the performance of the Eulerian transport model and to highlight small-scale …


Brittle Compressive Failure Of Salt-Water Columnar Ice Under Biaxial Loading, T. R. Smith, E. M. Schulson Jun 1993

Brittle Compressive Failure Of Salt-Water Columnar Ice Under Biaxial Loading, T. R. Smith, E. M. Schulson

Dartmouth Scholarship

The brittle failure of saline columnar ice was investigated under biaxial compression at and −10° and −40°C over the range 0 ≤ R A < 1 where R A is the ratio of the intermediate to major principal compressive stress. The major principal stress and the intermediate (confining) stress were orthogonal to the columnar axes (type-A confinement); both stresses and the c-axes of the grains were co-planar. The results confirm earlier work by Hausier (1981) and Timco and Frederking (1983, 1986) on saline ice and follow similar behavior to fresh-water columnar ice found by Smith and Schulson (1993) and Frederking (1977). Failure stress and failure mode are sensitive to the confinement and two regimes of behavior are found: the failure stress first rapidly increases with R A in the range 0 ≤ R A < R T and then tends to decrease for R A > R t. The transition stress ratio, R t changes from ≈0.2 at −10°C to ≈0.1 at −40°C. The failure mode changes from axial splitting to shear faulting in the loading plane for 0 < R A < R t. Above R t failure changes to a combined mode of splitting across the columns and shear faulting out of the loading plane. The failure-stress envelope is of a truncated Coulomb-type. Damage studies show wing cracks and local fragmentation of grains involving the brine pockets. The results are explained in terms of Coulombic sliding and Hertzian crack mechanics.


Organizing From The Ground Up: Watershed Initiatives: The Recent Truckee River Experience, Robert S. Pelcyger Jun 1993

Organizing From The Ground Up: Watershed Initiatives: The Recent Truckee River Experience, Robert S. Pelcyger

Water Organizations in a Changing West (Summer Conference, June 14-16)

15 pages.


New Legislative Approaches, Laird Noh Jun 1993

New Legislative Approaches, Laird Noh

Water Organizations in a Changing West (Summer Conference, June 14-16)

7 pages.


Water And Communities: Emerging Issues For Water Organizations, A. Lee Brown, Jr. Jun 1993

Water And Communities: Emerging Issues For Water Organizations, A. Lee Brown, Jr.

Water Organizations in a Changing West (Summer Conference, June 14-16)

13 pages.

Contains 2 pages of references.


Fort Collins And The Cache La Poudre River: An Integrated Greenway Vision, Kari V. Henderson Jun 1993

Fort Collins And The Cache La Poudre River: An Integrated Greenway Vision, Kari V. Henderson

Water Organizations in a Changing West (Summer Conference, June 14-16)

16 pages.

Contains references.


Programs For Obtaining Future Supplies Of Water For Southern California, Duane L. Georgeson Jun 1993

Programs For Obtaining Future Supplies Of Water For Southern California, Duane L. Georgeson

Water Organizations in a Changing West (Summer Conference, June 14-16)

19 pages (includes map).


Public And Private Options For Evolving Water Organizations, Tim De Young, Duane Brown Jun 1993

Public And Private Options For Evolving Water Organizations, Tim De Young, Duane Brown

Water Organizations in a Changing West (Summer Conference, June 14-16)

45 pages.


Overview Of Kansas Groundwater Management Districts: Their Duties, Authorities And Expectations, Wayne A. Bossert Jun 1993

Overview Of Kansas Groundwater Management Districts: Their Duties, Authorities And Expectations, Wayne A. Bossert

Water Organizations in a Changing West (Summer Conference, June 14-16)

8 pages.

Contains references.


Water Issues Facing Acequia Associations, Dennis Chavez Jun 1993

Water Issues Facing Acequia Associations, Dennis Chavez

Water Organizations in a Changing West (Summer Conference, June 14-16)

4 pages.


Navajo Nation’S Department Of Water Resources Management, Teresa M. Showa Jun 1993

Navajo Nation’S Department Of Water Resources Management, Teresa M. Showa

Water Organizations in a Changing West (Summer Conference, June 14-16)

13 pages (includes illustrations and 1 map).


Organizational Structure, Responsibilities And Authority: Northern Colorado Water Conservancy District, Larry Simpson Jun 1993

Organizational Structure, Responsibilities And Authority: Northern Colorado Water Conservancy District, Larry Simpson

Water Organizations in a Changing West (Summer Conference, June 14-16)

3 pages.


Approaches To Improved Irrigation Water Conservation Under Consideration By Northwest Kansas Groundwater Management District No. 4, Wayne A. Bossert Jun 1993

Approaches To Improved Irrigation Water Conservation Under Consideration By Northwest Kansas Groundwater Management District No. 4, Wayne A. Bossert

Water Organizations in a Changing West (Summer Conference, June 14-16)

13 pages.

Contains references.


The Central Utah Project Completion Act, P. Kirt Carpenter, Karen M. Ricks Jun 1993

The Central Utah Project Completion Act, P. Kirt Carpenter, Karen M. Ricks

Water Organizations in a Changing West (Summer Conference, June 14-16)

10 pages.


The Relevance Of Water “Ownership” To Water Markets And Other Issues, Barton H. Thompson, Jr. Jun 1993

The Relevance Of Water “Ownership” To Water Markets And Other Issues, Barton H. Thompson, Jr.

Water Organizations in a Changing West (Summer Conference, June 14-16)

31 pages.

Contains references.


Prediction And Management Of Sediments Load And Phosporus In The Beaver Reservoir Watershed Using A Geographic Information System, J. M. Mckimmey, H. D. Scott Jun 1993

Prediction And Management Of Sediments Load And Phosporus In The Beaver Reservoir Watershed Using A Geographic Information System, J. M. Mckimmey, H. D. Scott

Arkansas Water Resources Center Technical Reports

A study was conducted to compile a GIS database for the Beaver Reservoir Watershed and then use the database to run the Universal Soil Loss Equation and the Phosphorus Index Model on the War Eagle Creek Watershed, a portion of the Beaver Reservoir Watershed database. Characterization of the spat i a 1 properties of the primary attributes compiled for the watershed were reported. In addition, water quality samples taken from War Eagle Creek were analyzed for relationships across the watershed. Erosion in the watershed was lower than expected with well vegetated and fertilized pastures contributing to the reduction of annual …


Acoustic Properties Of Fine‐Grained Sediments From Emerald Basin: Toward An Inversion For Physical Properties Using The Biot–Stoll Model, Robert C. Courtney, Larry A. Mayer Jun 1993

Acoustic Properties Of Fine‐Grained Sediments From Emerald Basin: Toward An Inversion For Physical Properties Using The Biot–Stoll Model, Robert C. Courtney, Larry A. Mayer

Affiliate Scholarship

Acoustic data from two long cores, comprising marine clays and silts taken from Emerald Basin off Nova Scotia, are presented. High‐resolution measurements of compressional wavevelocity,attenuation, and power law exponent are made using ultrasonic frequencies between 100 to 1000 kHz. The observed values of the frequency dependence of attenuation suggest that a nonconstant Q mechanism is needed to explain these data, and Biot–Stoll theory is used to model the experimental results. An inversion scheme is used to constrain physical parameters in the Biot–Stoll dispersion relation. The inversion shows that there is a restricted range of permeability and grain size. By assigning …


Laboratory Studies Of Filter Pack Grain-Size Distributions And Hydrophobic Treatments To Enhance The Recovery Of Free-Phase Floating Hydrocarbons, Hugh Garret Heuvelhorst Jun 1993

Laboratory Studies Of Filter Pack Grain-Size Distributions And Hydrophobic Treatments To Enhance The Recovery Of Free-Phase Floating Hydrocarbons, Hugh Garret Heuvelhorst

Masters Theses

Experiments were conducted in laboratory sand tanks to evaluate filter pack design criteria in an effort to improve free-product hydrocarbon recovery from sand aquifers. Filter sands were prepared and installed in the test tanks to examine the relative efficiency of two different grain sizes and two different grain-size distributions to imbibe kerosene from the formation sand and release it to their respective wells. Treatments of different chemical products were applied to other filter sands to create a hydrophobic coating on the grains. The hydrophobic coatings were tested on filter sands of different grain sizes and grain-size distributions and compared to …


Westhazel General Petroleums Pool: Case History Of A Salt- Dissolution Trap In West-Central Saskatchewan, Canada, Neil Lennart Anderson, Dale A. Cederwall Jun 1993

Westhazel General Petroleums Pool: Case History Of A Salt- Dissolution Trap In West-Central Saskatchewan, Canada, Neil Lennart Anderson, Dale A. Cederwall

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The Westhazel General Petroleums (GP) Pool of west-central Saskatchewan, Canada, produces from the GP member of the Lower Cretaceous Mannville Group. This reservoir is structurally closed across the updip, eastern dissolutional edge of the underlying Middle Devonian rock salt of the Leofnard Member, Prairie Formation. The leaching of these salts occurred in post-Mannville time in the Westhazel area and caused the regional southwest dip of the General Petroleums member to be locally reversed.The Westhazel GP Pool, from a geophysical perspective, is characteristic of many of the shallow Lower Cretaceous pools situated along the dissolutional edge of the Prairie salt. The …