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Articles 283561 - 283590 of 304258

Full-Text Articles in Physical Sciences and Mathematics

Synergistic Effects In Bimetallic Hydrogenation Catalysts, Kathleen L. Mcintyre Jan 1985

Synergistic Effects In Bimetallic Hydrogenation Catalysts, Kathleen L. Mcintyre

Retrospective Theses and Dissertations

Mono and bimetallic catalysts of varying composition were prepared in order to examine any synergistic effect that may occur by mixing metals on a support. The test reactions were hydrogenation of 1, 3-butadiene and piperylene, a mixture of similar boiling 5-carbon olefins. Catalysts containing ruthenium and rhodium displayed some synergistic effects when supported on silica gel and 13X molecular sieves. The use of 5A molecular sieves as a support was used to examine the feasibility of selective hydrogenation as a separation tool for the piperylene mixture.

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Comparison Of Bootstrap And Jacknife Statistical Procedures, Amanuel Gobena Jan 1985

Comparison Of Bootstrap And Jacknife Statistical Procedures, Amanuel Gobena

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

This report compares the bootstrapping to jacknifing statistical procedures in terms in bias, confidence interval and estimation of median. Related literature have been reviewed. A bootstrap allows a researcher to get an approximation to the distribution of possibly complicated statistical summaries. It is based on random sampling with replacement from experimental units. Jacknife has also been in operation prior to bootstrapping statistical procedure. The jacknife divides the data into subgroups and obtains partial estimates of these subgroups by omitting one subgroup at a time. When both of these statistical resampling procedures are compared the bootstrap has less bias, more accurate …

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Shire Of Rockingham : A Study Of Land Resources And Planning Considerations, Veronica P M Oma, N L B Richards, M R. Wells Jan 1985

Shire Of Rockingham : A Study Of Land Resources And Planning Considerations, Veronica P M Oma, N L B Richards, M R. Wells

Resource management technical reports

No abstract provided.

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Efficiency Of Two Black-Tailed Prairie Dog Rodenticides And Their Impacts On Non-Target Bird Species, Anthony Dean Apa Jan 1985

Efficiency Of Two Black-Tailed Prairie Dog Rodenticides And Their Impacts On Non-Target Bird Species, Anthony Dean Apa

Electronic Theses and Dissertations

In 1983 zinc phosphide, strychnine with prebait, and strychnine without prebait were applied to black-tailed prairie dog (Cynomys ludovicianus) colonies in west-central South Dakota. Short-term (4 days later) and long-term (1 year later) poison efficiency and impact (short-term and long-term) on horned larks (Eromophila alpestrus) and other seed-eating birds of the prairie dog colonies were evaluated. Prairie dog burrow densities ranged from 54-187 burrows/ha with an average burrow density of 114 ±8 (± SE) burrows/ha. Rodenticide short-term control reduced active burrows by 95% with zinc phosphide, 42% with only strychnine, and 78% with prebaited strychnine. More zinc phosphide was consumed …

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Evaluation Of Seasonal Habitat Use By White-Tailed Deer In Eastern South Dakota, Thomas James Kramlich Jan 1985

Evaluation Of Seasonal Habitat Use By White-Tailed Deer In Eastern South Dakota, Thomas James Kramlich

Electronic Theses and Dissertations

Seasonal use of selected habitat types by white-tailed deer (Odocoileus virginianus) was investigated using radio telemetry locations during 1983 and 1984, on a predominantly agricultural area in east-central South Dakota. In the summer of 1983, radio-collared deer used corn, shelterbelts, and wetlands in proportion to their availability. Soybeans, grainfields, and grasslands were avoided. Deer selected shelterbelts in the fall and wetlands during the winter months, for protective cover. Habitat use shifted in the spring and shelterbelts received heavy use, once they became free of drifted snow. Shelterbelts continued to be selected by deer during the summer of 1984. IN the …

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Distribution, Temperature Selection, And Gonadal Development Of Fishes In A Power Plant Cooling Reservoir, Henry R. Maddux Jan 1985

Distribution, Temperature Selection, And Gonadal Development Of Fishes In A Power Plant Cooling Reservoir, Henry R. Maddux

Electronic Theses and Dissertations

The distribution, temperature selection, and gonadal development of fishes in the Big Stone Power Plant cooling reservoir were examined from July 1982 through July 1983. A total of 46.8% of the fishes captured during this study were from the discharge area, while 31.8% and 21.4% of the fish occurred in the mixing and intake areas, respectively. The mean water temperature occupied by common carp (Cyprinus carpio) ranged from 7.5 C in February to 31.2 C in August. Black bullheads (Ictalurus melas) were generally benthic and captured in the cooler water. The mean water temperature occupied by black bullheads ranged from …

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Evaluation Of Structure And Growth Of Bluegills And Black Bullheads Stocked With Largemouth Bass In South Dakota Farm Ponds, Charles E. Morris Jan 1985

Evaluation Of Structure And Growth Of Bluegills And Black Bullheads Stocked With Largemouth Bass In South Dakota Farm Ponds, Charles E. Morris

Electronic Theses and Dissertations

A two-year study estimated standing stock, growth, condition, survival rates, and population structure of bluegills (Lepomis macrochirus) and black bullheads (Ictalurus melas) stocked in South Dakota farm ponds with largemouth bass (Micropterus salmoides). Bluegills and black bullheads reproduced during the second growing seasons and by the end of the study three year-classes of fishes were present in most ponds. Mean back-calculated bluegill total lengths at annuli 1-3 were 58, 125, and 153 mm, respectively. Mean back-calculated black bullhead total lengths at annuli 1-3 were 82, 182, and 240 mm, respectively. A significant north vs south difference (P≤0.05) in third-year bullhead …

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Archaic And Late Prehistoric Adaptation In Southwestern Wyoming: The Frontier Pipeline Excavations, Alan R. Schroedl Jan 1985

Archaic And Late Prehistoric Adaptation In Southwestern Wyoming: The Frontier Pipeline Excavations, Alan R. Schroedl

Elusive Documents

No abstract provided.

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Historic Resource Study Bryce Canyon National Park, Nicholas Scrattish Jan 1985

Historic Resource Study Bryce Canyon National Park, Nicholas Scrattish

Elusive Documents

No abstract provided.

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Acidification Sources In Red Alder And Douglas-Fir Soils -- Importance Of Nitrification, H. Van Miegroet, D. W. Cole Jan 1985

Acidification Sources In Red Alder And Douglas-Fir Soils -- Importance Of Nitrification, H. Van Miegroet, D. W. Cole

Watershed Sciences Faculty Publications

Precipitation, throughfall, forest floor, and soil leachate samples were monitored continuously in 1981 and 1982 in a N-poor Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] forest and a red alder (Alnus rubra Bong.) forest growing adjacently on a glacial soil in western Washington. The purpose of the study was to quantify the relative importance of atmospheric vs. natural sources of H+ input to forest soil acidification, and to determine the role of N transformation processes in the overall H+ balance of soils with different N status. Rainwater samples had an avg pH of 4.7 and annual H+ deposition via precipitation averaged 320 …

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The Vertical Distribution And Feeding Chronology Of Larval Bear Lake Sculpin (Cottus Extensus) In Bear Lake, Utah-Idaho, D. Neverman Devroy, Wayne A. Wurtsbaugh, S. Ohlhorst Jan 1985

The Vertical Distribution And Feeding Chronology Of Larval Bear Lake Sculpin (Cottus Extensus) In Bear Lake, Utah-Idaho, D. Neverman Devroy, Wayne A. Wurtsbaugh, S. Ohlhorst

Watershed Sciences Faculty Publications

Preliminary sampling in Bear Lake, Utah/Idaho, with bottom trawls and larval fish nets indicate

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Effect Of The Interplanetary Magnetic Field Y Component On The High‐Latitude Nightside Convection, O. De La Beaujardiere, Vincent B. Wickwar, J D. Kelly, J H. King Jan 1985

Effect Of The Interplanetary Magnetic Field Y Component On The High‐Latitude Nightside Convection, O. De La Beaujardiere, Vincent B. Wickwar, J D. Kelly, J H. King

All Physics Faculty Publications

Sondrestrom radar observations reveal that the dawn‐dusk (By) component of the interplanetary magnetic field (IMF) strongly influences the nightside polar convection. This effect is quite complex. The convection for one orientation of By is not the mirror image of the other orientation. A positive By (i.e., pointing toward dusk) seems to organize the velocities such that, at all local times, they are predominantly westward within the radar field‐of‐view (≃68°‐to‐82° invariant latitude). Between dusk and midnight, on one such occasion, sunward flow is observed within the polar cap. In the midnight and dawn sectors, when By …

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Theoretical Study Of Anomalously High F Region Peak Altitudes In The Polar Ionosphere, Jan Josef Sojka, Robert W. Schunk Jan 1985

Theoretical Study Of Anomalously High F Region Peak Altitudes In The Polar Ionosphere, Jan Josef Sojka, Robert W. Schunk

All Physics Faculty Publications

During the last solar maximum period several observations of anomalously high F region peak altitudes have been made by the high latitude incoherent scatter radars. The observations indicate that there are several distinctive features associated with these high hmF2 ionospheric profiles: (1) they are observed near midnight with the plasma flowing out of the polar cap, (2) NmF2 ranges from 105 to 106 cm−3, (3) hmF2 ranges from 400 to 500 km, (4) below 300 km the profile is devoid of ionization, and (5) the observations are for solar maximum conditions. …

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Refilling Of Geosynchronous Flux Tubes As Observed At The Equator By Geos 2, Jan Josef Sojka, G. L. Wrenn Jan 1985

Refilling Of Geosynchronous Flux Tubes As Observed At The Equator By Geos 2, Jan Josef Sojka, G. L. Wrenn

All Physics Faculty Publications

During periods of extended quiet geomagnetic activity the geosynchronous satellite orbit lies inside the plasmasphere. Five such periods were observed by the GEOS 2 satellite. During the initial 48 hours of such periods the equatorial plasma flux tube density increases at 30 to 50 cm−3/day. However, on reaching ∼100 cm−3 the refilling rate decreases, and refilling is limited. Only when the density reaches ∼100 cm−3 do the plasma characteristics and fluctuations appear to be plasmaspheric and the flow predominantly corotational. The “hot outer zone” of the plasmasphere is highly structured in density and temperature when viewed …

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Universal Time Dependence Of Nighttime F Region Densities At High Latitudes, O De La Beaujardiere, Vincent B. Wickwar, G Caudal, J Holt, J D. Craven, L A. Frank, L Brace, D Evans, J D. Winningham, R A. Heelis Jan 1985

Universal Time Dependence Of Nighttime F Region Densities At High Latitudes, O De La Beaujardiere, Vincent B. Wickwar, G Caudal, J Holt, J D. Craven, L A. Frank, L Brace, D Evans, J D. Winningham, R A. Heelis

All Physics Faculty Publications

Coordinated EISCAT, Chatanika, and Millstone Hill incoherent scatter radar observations have revealed that in the auroral zone, the nighttime F region densities vary substantially with the longitude of the observing site: EISCAT’s densities are the largest and Millstone Hill’s are the lowest. The nighttime F region densities measured by the individual radars are not uniform: the regions where the densities are maximum are the so-called “blobs” or “patches” that have been reported previously. The observations are consistent with the hypothesis that the nighttime densities are produced in significant amounts not by particle precipitation, but by solar EUV radiation, and that …

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A Theoretical Study Of The Global F Region For June Solstice, Summer Maximum, And Low Magnetic Activity, Jan Josef Sojka, Robert W. Schunk Jan 1985

A Theoretical Study Of The Global F Region For June Solstice, Summer Maximum, And Low Magnetic Activity, Jan Josef Sojka, Robert W. Schunk

All Physics Faculty Publications

We constructed a time-dependent, three-dimensional, multi-ion numerical model of the global ionosphere at F region altitudes. The model takes account of all the processes included in the existing regional models of the ionosphere. The inputs needed for our global model are the neutral temperature, composition, and wind; the magnetospheric and equatorial electric field distributions; the auroral precipitation pattern; the solar EUV spectrum; and a magnetic field model. The model produces ion (NO+, O2+, N2+, N+, O+, He+) density distributions as a function of time. For our …

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Release Of A Thinned Budworm-Infested Douglas-Fir/Ponderosa Pine Stand, United States Department Of Agriculture, Forest Service Jan 1985

Release Of A Thinned Budworm-Infested Douglas-Fir/Ponderosa Pine Stand, United States Department Of Agriculture, Forest Service

Forestry

Current and past defoliation by western spruce budworm (Choristoneura occidentalis Freeman) in an 80-year-old predominantly Douglas-fir (Pseudotsuga menziesii var. glauca [Beissn.] Franco) stand thinned to 14 by 14 feet was significantly lower than in a nearby untreated stand of similar age, species, and site conditions. Analysis of periodic radial growth ratios indicated that prior to thinning, Douglas-fir had been heavily defoliated by budworm and growth was seriously depressed. Following thinning, the host leave trees developed dense crowns and 10-year radial growth increased an average of 57 percent: meanwhile, radial growth of nonhost ponderosa pine (Pinus ponderosa Dougl.) increased 38 percent. …

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Pinyon-Juniper Volume Equations For The Central Rocky Mountain States, United States Department Of Agriculture, Forest Service Jan 1985

Pinyon-Juniper Volume Equations For The Central Rocky Mountain States, United States Department Of Agriculture, Forest Service

Forestry

Gross cubic foot volume equations are now available for pinyon-juniper and several other woodland species in Nevada, Idaho, Utah, Colorado, Wyoming, and South Dakota. The volume equations are based on data collected as a subsample of woodland inventories conducted by Federal and State land management agencies. In these inventories, volumes of 4,705 trees were estimated by a visual sampling method.

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Costs Of Managing Nontimber Resources When Harvesting Timber In The Northern Rockies, United States Department Of Agriculture, Forest Service Jan 1985

Costs Of Managing Nontimber Resources When Harvesting Timber In The Northern Rockies, United States Department Of Agriculture, Forest Service

Forestry

When National Forest Timber is sold, land managers are required to protect other forest resources such as wildlife, soil and water, and scenic qualities. Measures taken to protect nontimber resources can raise administrative costs, lower the quantity of timber sold, and can reduce stumpage receipts. The costs of sale administration and the reduction in timber harvested can be readily derived from accounting and planning records. But little information is available on how much nontimber resources cost in terms of stumpage receipts. To provide such information, some 187 timber sales were studied on seven National Forests in the Northern Region between …

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Woodland Tree Volume Estimation: A Visual Segmentation Technique, United States Department Of Agriculture, Forest Service Jan 1985

Woodland Tree Volume Estimation: A Visual Segmentation Technique, United States Department Of Agriculture, Forest Service

Forestry

Visual segmentation, a technique for estimating cubic foot volume of woodland tree species, was compared with actual volume measurement. Comparison was made during a forest inventory of pinyon-juniper woodlands in Nevada and Utah. The visual technique's accuracy, its usefulness in developing volume equations, and applicability to volume inventory were studied. This study indicated visual segmentation is not reliable for estimating volume for a single tree. However, a sample of visually estimated volumes proved adequate for developing volume equations. In an application, a bias of 0 to -9 percent of the mean cubic foot volume per acre resulted from summary of …

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Attaining Visual Quality Objectives In Timber Harvest Areas - Landscape Architects' Evaluation, United States Department Of Agriculture, Forest Service Jan 1985

Attaining Visual Quality Objectives In Timber Harvest Areas - Landscape Architects' Evaluation, United States Department Of Agriculture, Forest Service

Forestry

When management activities such as timber harvest are undertaken on National Forest lands, landscape architects establish plans and guidelines so the project will meet a desired level of visual quality. This visual quality objective (VQO) for a given project is based on forest conditions, topography, and the type of viewing that is anticipated (viewing distance, number and type of visitors, etc.). Although landscape architects provide criteria and guidelines to achieve these visual objectives, there is no direct feedback mechanism with which to monitor the public's reaction or ascertain the extent to which visual objectives are met.

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Soil Water And Temperature In Harvested And Nonharvested Pinyon-Juniper Stands, United States Department Of Agriculture, Forest Service Jan 1985

Soil Water And Temperature In Harvested And Nonharvested Pinyon-Juniper Stands, United States Department Of Agriculture, Forest Service

Forestry

Tree harvesting increased soil water content, but the effect diminished over 4 years. The mean increase in soil water content was 2 to 4 percent the first year following harvest and 0 to 3 percent after 4 years. Although tree harvesting released soil water previously used by tree species, other biotic and abiotic demands increased. We speculate postharvest increases in wind and solar energy at the ground surface and increased understory transpiration in part explain the decline in soil water content differences between harvested and nonharvested plots over time.

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Effects Of Bifenox, Dcpa, And Napropamide On Ectomycorrhizal Development Of Conifer Seedlings In Central And Northern Rocky Mountain Nurseries, United States Department Of Agriculture, Forest Service Jan 1985

Effects Of Bifenox, Dcpa, And Napropamide On Ectomycorrhizal Development Of Conifer Seedlings In Central And Northern Rocky Mountain Nurseries, United States Department Of Agriculture, Forest Service

Forestry

Postseeding and postgermination treatments with three weed control herbicides (Bifenox, DCPA, Napropamide) at two rates of application caused little reduction of ectomycorrhizal development on 1- and 2-year-old conifer seedlings in Central or Northern Rocky Mountain nurseries. In many cases, herbicide treatment increased ectomycorrhizal development, particularly with DCPA. In general, herbicide treatment effects on ectomycorrhizal development were species and nursery specific.

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Measurement Of Field Resistance, Rust Hazard, And Deployment Of Blister Rust-Resistant Western White Pine, United States Department Of Agriculture, Forest Service Jan 1985

Measurement Of Field Resistance, Rust Hazard, And Deployment Of Blister Rust-Resistant Western White Pine, United States Department Of Agriculture, Forest Service

Forestry

Three white pine plantations, composed of materials of several levels of resistance from early generations of the blister rust resistance breeding program, were compared on the basis of annual infection and mortality rates. The sites varied in blister rust hazard; resistant materials were consistent in their performance, and the infection data behaved as one would expect if the genetic and environmental assumptions of the simple interest disease progress model were violated. Presumably, the resistant populations violate the genetic assumptions to the extent of their resistance, and any assessment of resistance performance must take into account both environmental as well as …

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Response Of Grass Species To Tree Harvesting In Singleleaf Pinyon-Utah Juniper Stands, United States Department Of Agriculture, Forest Service Jan 1985

Response Of Grass Species To Tree Harvesting In Singleleaf Pinyon-Utah Juniper Stands, United States Department Of Agriculture, Forest Service

Forestry

Cover, yield, and nutrient concentrations of grasses were sampled on tree-harvested and nonharvested plots on north, west, and south aspects of a singleleaf pinyon (Pinus monophylla)-Utah juniper (Juniperus osteosperma) stand. Grass cover increased rapidly the first 2 years following tree harvest, but the rate of increase declined over the next 2 years. Grass yield varied among aspects and soil microsites on tree-harvested plots but not on the nonharvested plots where tree competition masked aspect and microsite effects. All grass species had greater yield and greater percentage nitrogen and phosphorus on harvested than on nonharvested plots. Low digestibility of some species …

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Applying Height Growth And Site Index Curves For Inland Douglas-Fir, United States Department Of Agriculture, Forest Service Jan 1985

Applying Height Growth And Site Index Curves For Inland Douglas-Fir, United States Department Of Agriculture, Forest Service

Forestry

Methods for estimating both site index and dominant height growth for inland Douglas-fir in the Northern Rocky Mountains are presented and discussed. The methods should be applicable over a wide range of stand conditions because no restrictions were placed on species composition, stand density, spacing, or age structure in the original stem analysis sample. Increased accuracy can be obtained if habitat type is considered, because the shape of the site index curves varied with respect to three major habitat series groupings. Results are summarized in the form of equations, tables, and graphs. Precision curves are used to illustrate the relationship …

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Predicting Duff And Woody Fuel Consumed By Prescribed Fire In The Northern Rocky Mountains, United States Department Of Agriculture, Forest Service Jan 1985

Predicting Duff And Woody Fuel Consumed By Prescribed Fire In The Northern Rocky Mountains, United States Department Of Agriculture, Forest Service

Forestry

This paper presents numerical relationships of known precision for predicting duff consumption. They were established by assembling and analyzing data from three previous prescribed fire investigations and then testing them against other published data. Fuel loadings by diameter classes that differed among the studies were converted to a common set of diameter classes. The purpose of assimilating data from several studies was to develop predictive models that could be easily used by practitioners and that would apply over a wide range of conditions.

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An Application Of Discrete Optimization For Developing Economically Efficient Multiple-Use Projects, United States Department Of Agriculture, Forest Service Jan 1985

An Application Of Discrete Optimization For Developing Economically Efficient Multiple-Use Projects, United States Department Of Agriculture, Forest Service

Forestry

A discrete version of the continuous joint production model in economic theory is presented for use in designing multiple-use projects and identifying efficient management prescriptions for forest planning. Data requirements are less demanding than the continuous theoretical model, yet some of the more important features are maintained. Models can be formulated graphically or as mixed-integer programming problems that are easily solved via computerized routines.

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The Delphi Method: Application To Elk Habitat Quality, United States Department Of Agriculture, Forest Service Jan 1985

The Delphi Method: Application To Elk Habitat Quality, United States Department Of Agriculture, Forest Service

Wildlife Conservation and Management

This paper reports on the results of a study designed both to gather important information through Delphi and to evaluate several key features of the Delphi process. We intend to present information developed, and also describe and discuss Delphi so as to make resource managers more comfortable with it, aware of its potential, and willling to consider it along with other information gathering tools.

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Preliminary Geologic Map Of The Nephi 30' By 60' Quadrangle, Carbon, Emery, Juab, Sanpete, Utah, And Wasatch Counties, Utah, United States Geological Survey Jan 1985

Preliminary Geologic Map Of The Nephi 30' By 60' Quadrangle, Carbon, Emery, Juab, Sanpete, Utah, And Wasatch Counties, Utah, United States Geological Survey

All U.S. Government Documents (Utah Regional Depository)

The U.S. Geological Survey is engaged in a program of field studies designed to present the geologic framework of the United States on easily read topographic maps. The maps selected as a base for these geologic data are part of the Army Map Service (AMS) series of 1° by 2° quadrangles at a scale of 1:250,000. The Price, Utah AMS 1:250,000 quadrangle is one of these maps (fig.1). For certain areas, however, chiefly those sectors of the country involved in the Geological Survey's coal exploration program, the geologic data are being compiled on newly developed base maps at a scale …

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