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Articles 28501 - 28530 of 29947

Full-Text Articles in Geology

Corals Of The St. Louis Limestone In The Area Of Calhoun County, Illinois And St. Louis County, Missouri, William Earl Collins Jan 1973

Corals Of The St. Louis Limestone In The Area Of Calhoun County, Illinois And St. Louis County, Missouri, William Earl Collins

Masters Theses

"The St. Louis Limestone and its equivalent formations crop out from Alaska south to Sonora and from Arizona east to Virginia. The St. Louis, in most cases, is fossiliferous and contains numerous species of foraminifers, echinoderms, bryozoans, molluscans, brachipods, arthropods and coelenterates. Algal mounds and mats are common. The rugose coral fauna of the Middle Mississippian (Meramecian) St. Louis Limestone of southern Calhoun County, Illinois and northern St. Louis County, Missouri was studied to determine first what corals were present and second the validity of the names assigned to the previously described species. It was found that the binomen for …


Structure And Chemical Composition Of The Otoliths Of Cyprinus Carpio, Larry Paul Coen Jan 1973

Structure And Chemical Composition Of The Otoliths Of Cyprinus Carpio, Larry Paul Coen

Masters Theses

"The need for the study of microfossils such as foraminifera, conodonts, and otoliths as stratigraphic tools has been well established. However, disarticulated parts such as otoliths and conodonts cannot be effectively used unless they can be recognized. Otoliths, although somewhat unrecognized in the geological record, are far more abundant than articulated skeletons (Frizzell, 1965, p. 86). Therefore, much investigation is being conducted to reveal the origin, function, morphology, and usefulness of the otoliths of fishes.

In this investigation, the asteriscus, well developed only in Ostariophysins (of which the carp is a member), is studied for morphology. New tentative terms are …


Depositional Environments Of The Lower Tullock Formation (Paleocene), Slope County, Southwestern North Dakota, William K. Hickey Jan 1973

Depositional Environments Of The Lower Tullock Formation (Paleocene), Slope County, Southwestern North Dakota, William K. Hickey

Theses and Dissertations

The lower Tullock Formation (Paleocene), which consists of a section 5 to 30 feet thick, was studied in Slope County, southwestern North Dakota to determine its depositional environments. The lithol ogies present are sand, silt, clay and lignite. A bed of lignite or yellow silt marks the base of the Tullock Formation throughout the study area.

The silt beds are interpreted as having been deposited as natural levees because they are wedge-shaped and contain climbing ripple cross-stratification, interbedded sand lenses and lignitized paleo-raot systems. Well-drained swamp deposits are difficult to distinguish, but are probably located in the silt beds.

There …


Nebraska Groundwater Level (Decline & Rise), 1973 Jan 1973

Nebraska Groundwater Level (Decline & Rise), 1973

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Evaluation Of Nitrate Content Of Ground Water In Hall County, Nebraska, Rauf Piskin Jan 1973

Evaluation Of Nitrate Content Of Ground Water In Hall County, Nebraska, Rauf Piskin

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Regional Hydrothermal Alteration Of The Leadville Limestone (Mississippian) Of Central Colorado, L. V. Benson Jan 1973

Regional Hydrothermal Alteration Of The Leadville Limestone (Mississippian) Of Central Colorado, L. V. Benson

United States Geological Survey: Staff Publications

Massive metallic-sulfide deposits were implaced in the Leadville Limestone {Mississippian) of Central Colorado less than 70 million years ago. The thermal fluids which precipitated ore at Gilman, Colorado have regionally altered the Leadville Limestone. The sequence of alteration began with the recrystallization of limestone to a dark medium~grained dolomite containing a homogeneous distribution of Fe. This Was followed by partial recrystallization of the medium-grained dolomite to coarse-clear dolomite which contains an inhomogeneous distribution of Fe. The resulting banded rock is known as "zebra rock" . Precipitation of Si0 2 (jasperoid) occurred next. The jaspe=oid formed prior to the deposition of …


Hydrogeology Of A Sanitary Landfill, Mandan, North Dakota, Raymond D. Butler Jan 1973

Hydrogeology Of A Sanitary Landfill, Mandan, North Dakota, Raymond D. Butler

Theses and Dissertations

The data from this study can be applied to much of southwestern North Dakota because the geologic and climatic conditions are similar.

The Mandan landfill is on the Heart River floodplain and next to the river on the north and steep valley wall on the south. The sanitary landfill bas been used for over 20 years.

The only pre-Pleistocene unit exposed is the Cannonball Formation, which is interbedded sand, silt, and clay. Quaternary units consist of till, fluvial sand, silt, clay, and gravel, and eolian sand and silt.

A local flow system recharges on the upland next to the valley …


Ordovician Corals Of The Williston Basin Periphery, Frank P. Caramanica Jan 1973

Ordovician Corals Of The Williston Basin Periphery, Frank P. Caramanica

Theses and Dissertations

Tabulate and rugose corals are described from the Ordovician Red River) Stony Mountain, and Stonewall Formations in southern Manitoba and the Ordovician Bighorn Formation in northern Wyoming. Fifty-four species, 12 of which are new, are distributed in 20 genera. The Flower Model of coral evolution, based on wall microstructure of colonial corals, is extended to include the septa! Microstructure of colonial and solitary corals. "Primitive" corals are characterized by non t-rabeculate walls and septa whereas "advanced" forms are characterizedby trabeculate walls and septa. "Mid-range" corals are those with intermediate stages of trabecular development in walls .and septa. Corals in the …


Stratigraphic Comparison Of The Precambrian Wyman And Johnnie Formations In The Western Great Basin, California, Johnnie Nathan Moore Jan 1973

Stratigraphic Comparison Of The Precambrian Wyman And Johnnie Formations In The Western Great Basin, California, Johnnie Nathan Moore

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Precambrian Johnnie Formation in the Death Valley area and to the south is separable into two facies. The southern facies contains six distinct members: the transitional, quartzite, lower carbonate-bearing, siltstone, upper carbonate-bearing, and Rainstorm members. Dolomite, quartzite, and mudstone characterize the southern facies, as does the presence of the Johnnie oolite. To the north the Johnnie oolite pinches out and the amount of mudstone in the formation increases. The dominantly mudstone northern facies contains local gray limestone lenses closely similar to limestone in the Wyman Formation in the White-Inyo Mountains. Generally outcrops of the northern facies of the Johnnie …


Petrography, Diagenesis And Environment Of Deposition Of The Gasconade Formation, Lower Ordovician, Southern Missouri, Abd El-Aziz El-Hady A. Borahay Jan 1973

Petrography, Diagenesis And Environment Of Deposition Of The Gasconade Formation, Lower Ordovician, Southern Missouri, Abd El-Aziz El-Hady A. Borahay

Doctoral Dissertations

"The Gasconade Formation (Lower Ordovician) has been studied in the surface and subsurface in the Ozarks of Missouri and northeastern Oklahoma. The formation is mostly dolomite with a sandstone member at the base (Gunter) and frequent occurrences of chert bodies of different shapes particularly in the middle part.

The dolomite crystals in the lower and upper parts are subhedral to euhedral of equicrystalline to two-size fabric and range in size from 300-600 microns, and subhedral to anhedral of variable fabric and smaller size in the middle part. A sequence of cloudy and clear areas, named zoning, characterizes the euhedral crystals. …


Pleistocene Stratigraphy Of The Red Lake Falls Area, Minnesota, Kenneth L. Harris Jan 1973

Pleistocene Stratigraphy Of The Red Lake Falls Area, Minnesota, Kenneth L. Harris

Theses and Dissertations

Seven formations are present along a 50-mile stretch of the Red Lake River in Pennington, Red Lake, and Polk Counties, Minnesota. Five formations are largely glacial, sediment, and two are largely lacustr1ne sediment deposited during phases of Lake Agassiz.

The Gervais Formation (pre-Wisconsinan or early Wisconsinan) is mostly fluvial or lacustrine sediment modified by glacial ice of unknown source. The Marcoux Formation (pre Wisconsinan or Wisconsinan) is largely sediment deposited by glacial ice that advanced from the northeast over the Canadian Shield. The St. Hilaire. Formation (Wisconsinan) is mainly sediment deposited by glacial ice that advanced from a western or …


Latest Cenozoic Stratigraphy Of Lake Sakakawea Area, Northeast Mercer County, North Dakota, Donald Kieth Sackreiter Jan 1973

Latest Cenozoic Stratigraphy Of Lake Sakakawea Area, Northeast Mercer County, North Dakota, Donald Kieth Sackreiter

Theses and Dissertations

The latest Cenozoic in northeast Mercer County, North Dakota, is represented by five formations. They are, from bottom to top: the Charging Eagle Formation, the Medicine Hill Formation, the Snow School Formation, the Coteau Formation, and the Oahe Formation.

The Charging Eagle Formation is mainly fluvial sediment. Most of the sediment was derived from the west with only minor amounts from the northeast. It contains the first evidence of glaciation in the area.

The lower Medicine Hill Formation is mainly sediment deposited by a northeast-flowing ancestor of the Missouri River and by melt-water streams. The upp.er Medicine Hill Formation is …


Paleozoic Stratigraphy As An Ore Control Of Hydrothermal, Base-Metal, Sulfide Deposits In New Mexico, John Samuel Sullivan Jr. Jan 1973

Paleozoic Stratigraphy As An Ore Control Of Hydrothermal, Base-Metal, Sulfide Deposits In New Mexico, John Samuel Sullivan Jr.

Doctoral Dissertations

"Until now the concept or regional stratigraphic control of hydrothermal ore deposits has not received much attention in the literature as a possible exploration guide for locating additional ore bodies. This concept is applied on a regional scale to Paleozoic strata in thirteen mining districts with hydrothermal base-metal deposits in a 35,300 square mile area or southwest New Mexico.

The rocks at the stratigraphic position of the ore-zones are characterized as massive- to thick-bedded with less than 5 percent chert present. The rocks are abundantly to moderately fractured. Fine- to medium-grained dolomite is the dominant host-rock in the lower Paleozoic …


Investigation Of Present Thermal Regime Of Missouri River In Missouri, James C. Maxwell Dec 1972

Investigation Of Present Thermal Regime Of Missouri River In Missouri, James C. Maxwell

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The applicability of power spectral density techniques, Fourier series analysis, and linear regression to the mathematical modeling of river water temperature is demonstrated. Consideration is also given to the problem of estimating thermal inputs to rivers from man-made sources such as electrical power plants. First, power spectral density techniques are used in the time-series analysis of water temperature records which were taken from the Missouri River. Two spectral ranges are then studied from the standpoint of their applicability to (1) mathematical model building and (2) detection and identification of cyclic thermal inputs. Next, a Fourier regression fit to the time-series …


Epeirogenic And Climatic Controls Of Early Pleistocene Fluvial Sediment Dispersal In Nebraska, K. O. Stanley, William J. Wayne Dec 1972

Epeirogenic And Climatic Controls Of Early Pleistocene Fluvial Sediment Dispersal In Nebraska, K. O. Stanley, William J. Wayne

Department of Earth and Atmospheric Sciences: Faculty Publications

The change from Pliocene to Pleistocene fluvial sedimentation in Nebraska is denoted by gravel with relative enrichment of mechanically weak rock species and a two-fold increase in largest clast size. These changes in fluvial sediments suggest modification in degradational energy affecting detritus apparently related to deterioration of climate in the early Pleistocene. Cooler Pleistocene climates with increased moisture resulted in greater discharge and carrying capacity for streams headed in the Rocky Mountains and flowing across Nebraska. These streams carried granitic detritus eastward toward the continental glacier margin in easternmost Nebraska. There, streams flowing off ice sheets carrying sedimentary and metamorphic …


Gravity Survey Of The Mogolion Plateau Volcanic Province, Southwestern New Mexico., Douglas Hugh Krohn Dec 1972

Gravity Survey Of The Mogolion Plateau Volcanic Province, Southwestern New Mexico., Douglas Hugh Krohn

Earth and Planetary Sciences ETDs

A regional gravity survey has been conducted over the Mogollon Plateau, a mid-Tertiary volcano-tectonic complex 125 km in diameter located in southwestern New Mexico. The complete Bouguer gravity map (3 milligal contour interval) shows gravity values ranging form -167 milligals over an outcrop of Precambrian rocks near Silver City, on the southern rim of the Plateau to -251 milligals over an alluvium filled graben east of Reserve, in the northwestern part of the Plateau giving a maximum relief of 84 milligals. Gravity data show that in general the Mogollon Plateau is an area of low density rocks: gravity values within …


The Structural And Metamorphic History Of The Oakhurst Roof Pendant, Mariposa And Madera Counties, California, Lee R. Russell Dec 1972

The Structural And Metamorphic History Of The Oakhurst Roof Pendant, Mariposa And Madera Counties, California, Lee R. Russell

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Oakhurst roof pendant, near Oakhurst, California, consists of three pre-Cretaceous clastic metasedimentary rock units, surrounded and intruded by rocks of the Sierra Nevada batholith. Two zones of probable "sheared granitic" and "ultramafic" rocks trend northwesterly and are approximately aligned with the Foothills fault system farther north.

The dominant mesocopic feature of the pendant is a northwesterly striking foliation which forms a downward converging fan. Earlier-formed hornblende lineations have been transposed into this foliation plane, as shown by Schmidt-net projections.

Rocks comprising the three unites show three textural stages:

1) Early amphiboles and diopside overgrown by later static amphibole pophyroblasts. …


The Dacites Of The Washakie Needles, Bunsen Peak, And The Birch Hills, Wyoming, And Their Relationship To The Absaroka-Gallatin Volcanic Province, Linda Lou Anderson Love Dec 1972

The Dacites Of The Washakie Needles, Bunsen Peak, And The Birch Hills, Wyoming, And Their Relationship To The Absaroka-Gallatin Volcanic Province, Linda Lou Anderson Love

Earth and Planetary Sciences ETDs

ABSTRACT

TI1e Washakie Needles, Bunsen Peak, and Birch Hills dacites are three of many plugs which intrude the Eocene flows and volcaniclastic rocks of the Absaroka-Gallatin volcanic province. The dacites contain phenocrysts of plagioclase (oligoclase to andesine), biotite, and resorbed quartz. The dacites of the Washakie Needles and Bunsen Peak also contain phenocrysts of hornblende. The rocks of Bunsen Peak and the Birch Hills have two feldspar phases (oligoclase to andesine and sanidine) and quartz in the groundmass. The Washakie Needles dacite groundmass is composed of one feldspar (andesine to anorthoclase) and quartz. The fission track ages of the dacites …


The Geology Of The Pittsburg Landing Area, Snake River Canyon, Oregon-Idaho, David L. White Aug 1972

The Geology Of The Pittsburg Landing Area, Snake River Canyon, Oregon-Idaho, David L. White

All-Inclusive List of Electronic Theses and Dissertations

The major purpose of the study was to map, describe, and correlate the pre-Tertiary rocks. Accessible and excellent exposures at Pittsburg Landing enabled the writer to make a somewhat detailed study of the stratigraphy. The thesis area also offered an opportunity to study in a reconnaissance manner, the Tertiary Columbia River Basalt as described by Waters, and more recently y Ozier.


A New Species Of Menoceras From The Marsland Formation Of Nebraska, Lloyd G. Tanner Jul 1972

A New Species Of Menoceras From The Marsland Formation Of Nebraska, Lloyd G. Tanner

Bulletin of the University of Nebraska State Museum (1924–2023)

Further study indicates that the Menoceras remains collected from the "Bridgeport Quarries" (lower port:on or the Marsland Formation, Middle Miocene, of the Hemingford Group) are of a new species.

In 1962, these dicerathere remains were considered to be a geologic variety of Diceratherium niobrarensis (Stecher, Schultz, and Tanner). However, later (Tanner, 1969) a generic distinction was revived, separating the Menoceras Troxell from Diceratherium Marsh. Diceretherium niobrarensis was then placed in synonymy with Menoceras arikarense (Barbour).

The new species is an intermediate between Menoceras arikarense (Barbour) from the Harrison Formation and Menoceras marslandensis Tanner, from the upper portion of the Marsland …


Two Lynx-Like Cats From The Pliocene And Pleistocene, C. Bertrand Schultz, Larry D. Martin Jul 1972

Two Lynx-Like Cats From The Pliocene And Pleistocene, C. Bertrand Schultz, Larry D. Martin

Bulletin of the University of Nebraska State Museum (1924–2023)

A new species (Lynx stouti) of small felid is described from the lower Pliocene of Colorado. This form has several characters in common with the modern Lynx and may be ancestral to that genus. A new subspecies of Lynx issiodorensis Croizet and Jobert is described as L. i. kurteni from the Mullen Assemblage, Cherry County, Nebraska. The relationships of this form to other lynxes are discussed along with the paleo-distribution of the genus.

The classification of the felinae has always been somewhat controversial, especially at the generic level. One fairly homogenous group of cats which has been separated …


Geology And Ore Deposits Of The Southwest Nacimiento Range, Sandoval County, New Mexico, Otto L. Schumacher Jun 1972

Geology And Ore Deposits Of The Southwest Nacimiento Range, Sandoval County, New Mexico, Otto L. Schumacher

Earth and Planetary Sciences ETDs

The mapped area is in Sandoval County, New Mexico, 4 miles east of La Ventana. Precambrian rocks in the core of the Nacimiento uplift in this area consist mainly of quartz monzonite gneiss which has been intruded by granite. Hornblende schist xenoliths, zones of sheared quartz-plagioclase schistose gneiss, and mafic and leucocratic dike rocks are less abundant. Strata totaling 6200 feet, ranging from the Pennsylvanian Madera Formation through the Cretaceous Mancos Formation, are exposed in the area. Overlying the marine Madera Formation is 3400 feet of continental, marginal marine, and evaporite deposits consisting in ascending order of the Permian Abo, …


Phyletic Trends In Certain Lineages Of Quaternary Mammals, C. Bertrand Schultz, Lloyd G. Tanner, Lary D. Martin Jun 1972

Phyletic Trends In Certain Lineages Of Quaternary Mammals, C. Bertrand Schultz, Lloyd G. Tanner, Lary D. Martin

Bulletin of the University of Nebraska State Museum (1924–2023)

Evolutionary trends in certain carnivores, rodents, bovids, and proboscideans are examined. Chronoclines are demonstrated for muskrats, beavers, mammoths, and bison. The Pliocene-Pleistocene boundary and Quaternary climatic fluctuations are also discussed.

The University of Nebraska State Museum contains a large stratigraphically controlled collection of Pleistocene animals. This collection provides a unique opportunity for the study of phyletic trends in certain lineages of mammals. Although a few phylogenetic lineages have been proposed (Schultz and Frankforter, 1946; Hibbard, et al., 1965), this has not been done for the vast majority of Pleistocene mammals. However, there is much more data available than this would …


Structural Geology Of The Northern Part Of The East Helena Quadrangle, Lewis And Clark County, Montana., Jon A. Durham May 1972

Structural Geology Of The Northern Part Of The East Helena Quadrangle, Lewis And Clark County, Montana., Jon A. Durham

Earth and Planetary Sciences ETDs

The map-area is located along the northwest flank of the Big Belt Mountains, Montana and includes the Eldorado thrust which marks the zone of frontal breakthrough where thrusts of the Cordilleran foldbelt are in contact with the Rocky Mountain foreland. Sedimentary rocks range in age from Precambrian to Cretaceous. Two formations of the Precambrian Belt Series, the Greyson Shale (Oldest) and Spokane Shale are present. Overlaying the Spokane Shale are five formations of the Cambrian; Flathead Quartzite (oldest), Wolsey Shale, Meagher Limestone, Park Shale, and Pilgrim Limestone. Their total aggregate thickness is about 1200 feet.


A Geochemical Study Of Distribution Of Elements In Ores And Limestones From New Jersey Zinc Mines, Hanover, New Mexico, Dasharatham Sayala May 1972

A Geochemical Study Of Distribution Of Elements In Ores And Limestones From New Jersey Zinc Mines, Hanover, New Mexico, Dasharatham Sayala

Earth and Planetary Sciences ETDs

Limestone samples (424) from both surface and subsurface horizons in the New Jersey Zinc mines at Hanover have been analyzed by atomic absorption spectrophotometry for Ag, Cd, Mn, Pb, Zn, Cu and Sn. The lead­zinc ore bodies, occurring in Paleozoic limestones are a typical example of hydrothermal deposits; and are related to the Hanover intrusive. The distribution of trace elements in surface limestones was mainly due to primary dispersion, partly due to secondary dispersion. The depth of ore mineralization, concentration of element in ore solutions, porosity of limestones, diffusion coefficients of element, and the chemical nature of elements in the …


The Microtine Rodents Of The Mullen Assemblage From The Pleistocene Of North Central Nebraska, Larry D. Martin May 1972

The Microtine Rodents Of The Mullen Assemblage From The Pleistocene Of North Central Nebraska, Larry D. Martin

Bulletin of the University of Nebraska State Museum (1924–2023)

The University of Nebraska State Museum has had an active collecting program in Hooker and Cherry counties, Nebraska, since the 1930's. The following University of Nebraska State Museum collecting localities have been extensively excavated: Cr-10, Cr-102, Cr-11, Ho-101, Ho-102, and Ho-103. These localities have produced a large vertebrate fauna described by Jakway as the Mullen Local Fauna which he considered for the most part to be Early lllinoian. Further study of this local fauna now demonstrates that assemblage does include Early as well as Middle Pleistocene animals. The purpose of this paper is to report on the evidence regarding the …


Use Of Groundwater For Irrigation In Clay County, Nebraska, 1970, Eugene K. Steele Jr. May 1972

Use Of Groundwater For Irrigation In Clay County, Nebraska, 1970, Eugene K. Steele Jr.

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Groundwater Levels In Nebraska, 1971, C.F. Keech May 1972

Groundwater Levels In Nebraska, 1971, C.F. Keech

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Tertiary Igneous Rocks Of Northeastern Cache Valley, Idaho, Parry D. Willard May 1972

Tertiary Igneous Rocks Of Northeastern Cache Valley, Idaho, Parry D. Willard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The tuffs and limestones of the Tertiary Salt Lake Formation in northeastern Cache Valley, Franklin County, Idaho, are intruded by basic and intermediate igneous dikes and sills. The Tertiary intrusives are exposed in an area 10 miles long and 2 miles wide between Bear River and Maple Creek in the foothills of the Bear River Range east of Preston, Idaho. They trend north-northwest. The intrusives are mostly diabase but include a small body of syenodiorite and several small andesite dikes. The intrusives seem to be emplaced along early Basin and Range faults. They are limited to the Cache Valley Member …


Geology Of The Wildcat Hills, Utah, Ronald C. Howes May 1972

Geology Of The Wildcat Hills, Utah, Ronald C. Howes

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Wildcat Hills, located in Curlew Valley of northwestern Utah, are composed of a series of late Tertiary extrusive and dike rocks. Five volcanic rock types have been identified: an andesite, a rhyolite, a perlite, a basalt, and a welded tuff. Hydration of obsidian pellets contained in the flows has produced some of the perlite. Diatremes in the andesite attest to the high-volatile content and the explosive extrusion of some of the lavas. A compound basalt neck indicates that basalt was extruded at the Wildcat Hills and is not an erosional remnant of the basalt flow from the base of …