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Explanation Of Water-Level Hydrographs, P. B. Wigley, M. J. Ellis, G. V. Steele Jan 1991

Explanation Of Water-Level Hydrographs, P. B. Wigley, M. J. Ellis, G. V. Steele

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Groundwater-Level Changes In Nebraska, Predevelopment To Fall 1991, Conservation Survey Division Jan 1991

Groundwater-Level Changes In Nebraska, Predevelopment To Fall 1991, Conservation Survey Division

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Pleistocene Mammals From The South Sulphur River, Hunt County, Texas, Leo Carson Davis, Kenneth M. Ball Jan 1991

Pleistocene Mammals From The South Sulphur River, Hunt County, Texas, Leo Carson Davis, Kenneth M. Ball

Journal of the Arkansas Academy of Science

Preliminary collecting and excavating along the South Sulphur River has produced a diverse list of fossil mammals. The pampathere, Holmesina septentrionalis, and the large armadillo, Dasypus bellus, with their southern affinities from the extinct megafauna, were found in association with Microtus pennsylvanicus, which has a northern distribution at present. This combination of species argues for climatic conditions and biotic communities during the Pleistocene that have no modern counterparts.


A Seismic Analysis Of Black Creek And Wabumun Salt Collapse Features, Western Canadian Sedimentary Basin, Neil Lennart Anderson, Robert James Sidford Brown Jan 1991

A Seismic Analysis Of Black Creek And Wabumun Salt Collapse Features, Western Canadian Sedimentary Basin, Neil Lennart Anderson, Robert James Sidford Brown

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

These salt remnants and their associated collapse features are often associated with structural or stratigraphic traps. As a result of the relationships between dissolution and hydrocarbon entrapment, the distribution (areal extent and thickness) of these salt remnants is of significant interest to the explorationist. Seismic information about the thickness and the extent of these salts should be used together with well log control to generate subsurface distribution maps. These maps will facilitate both the delineation of prospective structural and stratigraphic play fairways and the determination of the timing of salt dissolution. In addition, an appreciation of regional salt distribution will …


Differential Compaction Of Winnipegosis Reefs: A Seismic Perspective, Neil Lennart Anderson, Evan K. Franseen Jan 1991

Differential Compaction Of Winnipegosis Reefs: A Seismic Perspective, Neil Lennart Anderson, Evan K. Franseen

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Winnipegosis Formation reefs in southern Saskatchewan are typically encased in the thick, apparently incompressible salts of the Prairie Evaporite. Illustrates the usefulness of seismic data to separate postdepositional compaction features from primary features to determine the primary morphology of a reef better and to determine the relative amounts of postdepositional compaction with the different reef environments.


Constraints On Unroofing Rates In The High Himalaya, Eastern Nepal, Mary S. Hubbard, L. H. Royden, K. V. Hodges Jan 1991

Constraints On Unroofing Rates In The High Himalaya, Eastern Nepal, Mary S. Hubbard, L. H. Royden, K. V. Hodges

Geosciences Faculty Publications

Thermobarometric data for samples across the Main Central thrust zone in eastern Nepal show an inversion in temperature but not in pressure. These data have been interpreted to represent a portion of the paleogeotherm at the time of Main Central thrust deformation. A 40Ar/39Ar age on hornblende (closure temperature (Tc)=500±50°C) constrains the timing of this deformation to be ∼21±0.2 Ma. The 40Ar/39Ar ages of other minerals (muscovite, Tc=350°C, age (t)=12.0±0.2 Ma; K-feldspar, Tc=220°C, t=8.0±0.2 Ma) from the same location further constrain the cooling history of this region. Together the geochronologic and thermobarometric data yield an average unroofing rate of 1.2±0.6 …


Geologic Highway Cross Section: Kentucky Highway 80, Hazard To Prestonburg, Donald R. Chesnut Jr. Jan 1991

Geologic Highway Cross Section: Kentucky Highway 80, Hazard To Prestonburg, Donald R. Chesnut Jr.

Map and Chart--KGS

Highway roadcuts along Kentucky Highway 80 from Hazard to Prestonsburg are scientifically significant exposures of the Pennsylvanian coal-bearing rocks of the Eastern Kentucky Coal Field, and provide an excellent educational opportunity. The coals exposed along this road are the most economically important of the coal field, and the roadcut exposures offer easy access and stratigraphic variety. They are ideal for high school, university, and professional geology field trips (Cobb and others, 1981). Several national and international field trips and many out-of-state university field trips have examined these exposures. In addition, studies in coal geology and petrography, paleontology, biostratigraphy, and elastic …


The Relationship Between Soil Properties And No-Tillage Agriculture, Robert L. Blevins Jan 1991

The Relationship Between Soil Properties And No-Tillage Agriculture, Robert L. Blevins

Soil Science News and Views

I am highly honored to be invited to present the 3rd annual S.H. Phillips Distinguished Lecture on No-Tillage Agriculture. My interest and subsequent research efforts in the area of no-tillage agriculture began in 1969. Shirley Phillips encouraged my efforts through his interest and enthusiasm for this rather radical and new approach to farming without the use of tillage equipment. At that time, Harry Young, a western Kentucky farmer and pioneer of no-tillage agriculture along with Shirley, Jim Herron, Charlie Slack and other co-workers were excited about the potential of this new, innovative farming system and what it could do for …


Fall Fertilization And Liming For Tobacco Production, J. L. Sims, Kenneth L. Wells Jan 1991

Fall Fertilization And Liming For Tobacco Production, J. L. Sims, Kenneth L. Wells

Soil Science News and Views

Proper nutrition of tobacco is a prerequisite for achieving high yields of cured leaf possessing desirable marketing characteristics. Together with the variety grown, soils, climate, and curing conditions, a desirable nutrient environment greatly influences yield, quality, and usability of the leaf produced. Late summer and early fall is a good time to select fields for future tobacco crops or to sample this year's tobacco fields which will be used for tobacco next year, and to assess their needs for lime, phosphorus, and potassium. Planning fertilization strategies this fall that lead to increased profit is much more effective than waiting until …


Farm Nutrient Management, William O. Thom Jan 1991

Farm Nutrient Management, William O. Thom

Soil Science News and Views

Nutrient management is becoming a buzz word in today's vocabulary of crop and livestock production. In the past it was applied to efficient management of all nutrient sources used for crop production. More recently it is being used to account for all nutrients used for crop production that are brought onto the farm, removed from the farm in crop and animal products, and reallocated within the farm unit. Nitrogen, phosphorus, and potassium are the nutrients of concern with nitrogen and phosphorus being most important.


Using Solid, Bulk Blended Mix-Grade Fertilizers, Kenneth L. Wells, Jonathan D. Green Jan 1991

Using Solid, Bulk Blended Mix-Grade Fertilizers, Kenneth L. Wells, Jonathan D. Green

Soil Science News and Views

Most solid, mixed fertilizers used in Kentucky are prepared by physically mixing two or more fertilizer materials to a desired analysis. The ingredient materials most commonly used to prepare mixed fertilizers in Kentucky are diammonium phosphate, urea, ammonium nitrate, muriate of potash, and sulfate of potash. During the period January - June, 1990, these 5 materials made up 60% of the 700,000 tons of fertilizer used in Kentucky. And just three of them ... urea, diammonium phosphate and muriate of potash ... made up 47% of the total used during that period.


Managing Soil Content Of Nitrate Nitrogen, Kenneth L. Wells Jan 1991

Managing Soil Content Of Nitrate Nitrogen, Kenneth L. Wells

Soil Science News and Views

The concerns about leaching of fertilizer nitrogen (N} into groundwater which were raised in the late 1960's were largely silenced during the 1970's as our agricultural economy was massively expanded. But since the early 80's they have been raised again to the point that national legislation (the Clean Water Act) was put into place to bring purity of the nation's water supplies into compliance with EPA-established standards. Beyond the apprehension largely about nitrate (NO3) levels in groundwater, the groundwater issue today also includes concerns about pesticides. At the current time, the public is apprehensive about drinking water and …


Mineralization And Hydrocarbon Emplacement In The Cambrian-Ordovician Mascot Dolomite Of The Knox Group In South-Central Kentucky, Warren H. Anderson Jan 1991

Mineralization And Hydrocarbon Emplacement In The Cambrian-Ordovician Mascot Dolomite Of The Knox Group In South-Central Kentucky, Warren H. Anderson

Report of Investigations--KGS

The Mascot Dolomite, the upper unit of the Cambrian-Ordovician Knox Group, is a major host for Mississippi Valley-type ore deposits and petroleum in south-central Kentucky. The Mascot was deposited on a broad, shallow platform that exhibited unusually uniform conditions of deposition, ranging from supratidal to shallow subtidal environments. The formation has a complex diagenetic history, including several stages of dolomitization, silicification, solution, and brecciation. Diagenesis and, to some extent, deposition were influenced by Early Ordovician tectonic activity. Tectonic activity influenced development of a regional unconformity during Middle Ordovician time. Evidence of this tectonic activity includes up to 300 feet of …


The Kinetics Of Organic Matter Mineralization In Anoxic Marine Sediments, David J. Burdige Jan 1991

The Kinetics Of Organic Matter Mineralization In Anoxic Marine Sediments, David J. Burdige

OES Faculty Publications

The kinetics of sulfate reduction and inorganic nutrient production (ΣCO2, ammonium, and phosphate) were examined in the sediments at five sites in the southern Chesapeake Bay, using long term (> 200 d) sediment decomposition experiments. Average first order rate constants for these processes (at 25oC) decreased from 8.2 to 3.7 yr-1 in the surface sediments (0-2 cm), to 2.1 to 0.2 yr-1 at 12-14 cm. The C/N and C/P ratios of the organic matter undergoing decomposition also increased with depth at these sites. Taken together, these results indicate that the reactivity of the organic matter …


Aspects Of Sporinite Chemistry, Michael A. Kruge, John C. Crelling, Edwin J. Hippo, Stephen R. Palmer Jan 1991

Aspects Of Sporinite Chemistry, Michael A. Kruge, John C. Crelling, Edwin J. Hippo, Stephen R. Palmer

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

With the recent advent of the ability to separate coal into maceral concentrates of high purity, the individual constituents of coal can now be analyzed separately, without their mutual interference, giving a much better understanding of the macromolecular structure of coal. The sporinites from two Pennsylvanian age coal samples (Illinois Basin, U.S.A.) were studied, one from a vitrinite-rich high-volatile bituminous coal, the other from a liptinite-rich high-volatile bituminous coal of slightly higher rank. Sporinites were isolated from each coal by density gradient centrifugation. The sporinite of the vitrinite-rich coal was compared chemically and petrographically with the parent coal and with …


A Monte Carlo Study Of Rainfall Sampling Effect On A Distributed Catchment Model, Witold F. Krajewski, Venkataraman Lakshmi, Konstantine P. Georgakakos, Subhash C. Jain Jan 1991

A Monte Carlo Study Of Rainfall Sampling Effect On A Distributed Catchment Model, Witold F. Krajewski, Venkataraman Lakshmi, Konstantine P. Georgakakos, Subhash C. Jain

Faculty Publications

A Monte Carlo study of a physically based distributed-parameter hydrologic model is described. The catchment model simulates overland flow and streamflow, and it is based on the kinematic wave concept. Soil Conservation Service curves are used to model rainfall excess within the basin. The model was applied to the Ralston Creek watershed, a small (7.5 km2) rural catchment in eastern Iowa. Sensitivity of the model response with respect to rainfall-input spatial and temporal sampling density was investigated. The input data were generated by a space-time stochastic model of rainfall. The generated rainfall fields were sampled by the varied-density …


Radon Deposits In Nebraska, R. R. Burchett Jan 1991

Radon Deposits In Nebraska, R. R. Burchett

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


A Detailed Gravity Study Over A Known Devonian Carbonate Buildup: The Shell Golden Reef, Northwestern North Dakota, Stephen M. Braun Jan 1991

A Detailed Gravity Study Over A Known Devonian Carbonate Buildup: The Shell Golden Reef, Northwestern North Dakota, Stephen M. Braun

Theses and Dissertations

A detailed gravity study was conducted over the Shell Golden reef in the northwestern North Dakota portion of the Williston Basin. The Shell Golden reef has been previously interpreted to be reefal facies within the Winnipegosis Formation (Devonian) located at a depth of about 2400 meters. Based only on information from wireline logs and core from two boreholes, the Shell Golden well #34X-34 has been previously interpreted as a pinnacle reef with 70 meters of relief and undetermined diameter. The basin regime of the Elk Point shelf created an environment that allowed the growth and development of the Shell Golden …


Erosion Of Fractured Banks, Lake Sakakawea, Western North Dakota, Mark C. Elliott Jan 1991

Erosion Of Fractured Banks, Lake Sakakawea, Western North Dakota, Mark C. Elliott

Theses and Dissertations

Shoreline erosion at Lake Sakakawea has exceeded originally predicted rates. This thesis is a continuation of a project, begun in 1983, to study erosion rates, causes, and prediction; the purpose has been to describe variations in fracture patterns in shoreline banks and assess their affects on erosion rates.

During the first phase of this project (1983-1986), average bank recession was rapid (l.Sm/yr) and factors related to wave action, including fetch, bank orientation, and beach composition, were most important. Since 1986, low lake levels have persisted and wave action has not been a factor; however banks continue to recede, but at …


Fracture-Enhanced Porosity And Permeability Trends In The Bakken Formation, Williston Basin, Western North Dakota, Wayne B. Freisatz Jan 1991

Fracture-Enhanced Porosity And Permeability Trends In The Bakken Formation, Williston Basin, Western North Dakota, Wayne B. Freisatz

Theses and Dissertations

Fractures play a critical role in oil production from the Bakken Formation (Devonian and Mississippian) in the North Dakota portion of the Williston Basin. The Bakken Formation in the study area is known for its low matrix porosity and permeability, high organic content, thermal maturity, and relative lateral homogeneity. Core analysis has shown the effective porosity and permeability development within the Bakken Formation to be primarily related to fracturing.

In theory, lineaments mapped on the surface reflect the geometry of basement blocks and the zones of fracturing propagated upward from them. Fracturing in the Williston Basin is thought to have …


Hydrogeology Of Thrust Faults And Crystalline Thrust Sheets: Results Of Combined Field And Modeling Studies, Craig B. Forster, James P. Evans Jan 1991

Hydrogeology Of Thrust Faults And Crystalline Thrust Sheets: Results Of Combined Field And Modeling Studies, Craig B. Forster, James P. Evans

Geosciences Faculty Publications

Field, laboratory, and modeling studies of faulted rock yield insight into the hydraulic character of thrust faults. Late‐stage faults comprise foliated and subparallel faults, with clay‐rich gouge and fracture zones, that yield interpenetrating layers of low‐permeability gouge and higher‐permeability damage zones. Laboratory testing suggests a permeability contrast of two orders of magnitude between gouge and damage zones. Layers of differing permeability lead to overall permeability anisotropy with maximum permeability within the plane of the fault and minimum permeability perpendicular to the fault plane. Numerical modeling of regional‐scale fluid flow and heat transport illustrates the impact of fault zone hydrogeology on …


Slickenside Petrography: Slip-Sense Indicators And Classification, Young-Joon Lee Jan 1991

Slickenside Petrography: Slip-Sense Indicators And Classification, Young-Joon Lee

Geology Theses and Dissertations

Petrographic study has been carried out on slickenside thin sections, to find out reliable microstructures for determining the slip-sense of faults, and to classify slickensides morphologically. Thin sections are made cut parallel to the striation and perpendicular to the slip plane. Many useful slip-sense indicators are found in thin section even though such indicators may be absent in hand specimens. They are (1) off-set or bending of once-continuous bodies such as veins, layers, grains or twin lamellae, (2) crystal fibers growing nearly parallel to the slip direction, (3) extensional fractures aligned oblique to the slip plane, (4) S-C geometries in …


Mineral Paragenesis Of The Granulite Facies In The Lake George Area, New York, Boknam Ree Jan 1991

Mineral Paragenesis Of The Granulite Facies In The Lake George Area, New York, Boknam Ree

Geology Theses and Dissertations

The Lake George Area belongs to the southeastern part of the Adirondack Highlands. The rocks of this area show variations in mineral assemblages which are caused by differences in bulk chemical composition. This makes it unsuccessful to use a subdivision of the granulite facies which is suggested by de Waard (1965).
The CFM diagram (Abbott, 1982) is used to show the relationship between composition and paragenesis of the Lake George Area. In this study, a different result has been found in the order of partitioning of Fe between coexisting minerals, namely, garnet>hornblende>biotite>orthopyroxene>clinopyroxene. The hornblende granitic gneiss …


Evaluation Of Computational Methods Of Paleostress Analysis Using Fault-Striation Data, Steven Henry Schimmrich Jan 1991

Evaluation Of Computational Methods Of Paleostress Analysis Using Fault-Striation Data, Steven Henry Schimmrich

Geology Theses and Dissertations

Over the past 12 years, many different computational methods or variations of existing methods have been proposed for determining paleostress tensors from fault populations and their slip directions. These methods are all based upon well-known relationships between stress and shear and use iterative, non-linear mathematical algorithms which seek to minimize the angles between the calculated maximum shear stress direction and the observed movement directions on each fault plane in a population. The solution returned is the best-fit paleostress tensor for the population.
By taking the Coulomb failure criterion into account, several paleostress analysis programs have been able to use linear, …


The Pangaean Megamonsoon- Evidence From The Upper Triassic Chinle Formation, Colorado Plateau, Russell F. Dubiel, Judith Totman Parrish, J. Michael Parrish, Steven C. Good Jan 1991

The Pangaean Megamonsoon- Evidence From The Upper Triassic Chinle Formation, Colorado Plateau, Russell F. Dubiel, Judith Totman Parrish, J. Michael Parrish, Steven C. Good

United States Geological Survey: Staff Publications

The Upper Triassic Chinle Formation was deposited at an exceptional time in Earth's paleogeographic and paleoclimatic history. During the Triassic, the supercontinent Pangaea was at its greatest size, in terms of both aggregated continental crust and exposed land area. Moreover, the exposed land was divided symmetrically about the paleoequator between the northern and south- ern hemispheres. These conditions were ideal for maximizing monsoonal circulation, as predicted from paleoclimate models. The Chinle was deposited between about 5° to 15° N paleolatitude in the western equatorial region of Pangaea, a key area for documenting the effects of the monsoonal climate. This study …


Low-Silica And High-Calcium Stone In The Newman Limestone (Mississippian) On Pine Mountain, Harlan County, Southeastern Kentucky, Garland R. Dever Jr., Jack R. Moody, Thomas L. Robl, Lance S. Barron Jan 1991

Low-Silica And High-Calcium Stone In The Newman Limestone (Mississippian) On Pine Mountain, Harlan County, Southeastern Kentucky, Garland R. Dever Jr., Jack R. Moody, Thomas L. Robl, Lance S. Barron

Information Circular--KGS

The coal industry of Kentucky is an important market for limestone. Coal producers use limestone as rock dust for explosion abatement in underground coal mines and as a neutralizing agent in surface-mine reclamation and acid-drainage control. Crushed stone is also used for constructing and maintaining haulage roads.

In the Eastern Kentucky Coal Field, the coal-bearing rocks of Pennsylvanian age generally do not contain limestones that are thick enough to quarry or mine economically. But movement on the Pine Mountain overthrust fault has brought the Newman Limestone (Mississippian) to the surface along Pine Mountain in the southeastern part of the coal …


Paleontological Survey Of The Pennsylvanian Rocks Of The Eastern Kentucky Coal Field: Part 1, Invertebrates, Donald R. Chesnut Jr. Jan 1991

Paleontological Survey Of The Pennsylvanian Rocks Of The Eastern Kentucky Coal Field: Part 1, Invertebrates, Donald R. Chesnut Jr.

Information Circular--KGS

Morse (1931) conducted the last paleontological survey of the Eastern Kentucky Coal Field almost 60 years ago. Substantial new information generated by mapping, as well as sedimentological, stratigraphic, and paleontological studies, now justify a new paleontological survey of these rocks. This survey is a compilation of both the new and old information.

Lithologic analysis reveals at least 41 marine zones in the coal field. Paleontological analysis shows that a variety of faunal communities existed, and many of the marine zones contain abundant and diverse faunal assembleges. However, the biostratigraphic resolution of invertebrate fossils is apparently very poor compared to the …


Annual Installation Of Irrigation Wells In Nebraska Through 1990, Conservation Survey Division Jan 1991

Annual Installation Of Irrigation Wells In Nebraska Through 1990, Conservation Survey Division

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Groundwater Levels In Nebraska, 1990, Gregory V. Steele, Perry B. Wigley Jan 1991

Groundwater Levels In Nebraska, 1990, Gregory V. Steele, Perry B. Wigley

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Potential Effects Of Climate Change On Milk Production And Conception Rate In Dairy Cattle In The United States And Western Europe, Peggy Lea Klinedinst Jan 1991

Potential Effects Of Climate Change On Milk Production And Conception Rate In Dairy Cattle In The United States And Western Europe, Peggy Lea Klinedinst

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

No abstract provided.