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Geology Of The West-Central Part Of The Malad Range, Idaho, Phillip H. Wach May 1967

Geology Of The West-Central Part Of The Malad Range, Idaho, Phillip H. Wach

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The west-central part of the Malad Range is located in south-eastern Idaho. This area was the site of thick marine deposition in the early Paleozoic period. In the Tertiary and Quaternary periods continental deposition occurred, covering the Paleozoic rocks. Quartzite and shale units of the Brigham Quartzite are found near the base of the Cambrian section. Carbonate with shale interbeds is found in the middle and late Cambrian units. Limestone and silty limestone are found in the early and middle Ordovician time overlain by the middle Ordovician Swan Peak Quartzite. The Laketown Dolomite includes units of late Ordovician and Silurian …


The Brule-Gering (Oligocene-Miocene) Contact In The Wildcat Ridge Area Of Western Nebraska, C. Bertrand Schultz, Charles H. Falkenbach, Carl F. Vondra Jan 1967

The Brule-Gering (Oligocene-Miocene) Contact In The Wildcat Ridge Area Of Western Nebraska, C. Bertrand Schultz, Charles H. Falkenbach, Carl F. Vondra

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

The contact between the Brule Formation (Oligocene) and the Gering Formation (Miocene) can be readily distinguished in the Wildcat Ridge area, as elsewhere in western Nebraska. At the critical fossiliferous exposures at Castle Rock in Scotts Bluff County, the contact on the south face between the two formations is defined as 129 feet above the base of the "Upper Ash" bed, which corresponds to the upper portion of Darton's (1899, PI. C, Fig. D, following p. 754) "sandy phase" in the upper part of the Brule. Certain key beds in the Gering Formation can be traced laterally from a channel …


A Stratigraphic And Sedimentologic Analysis Of The Tongue River And Sentinel Butte Formations (Paleocene), Western North Dakota, Chester F. Royse Jr. Jan 1967

A Stratigraphic And Sedimentologic Analysis Of The Tongue River And Sentinel Butte Formations (Paleocene), Western North Dakota, Chester F. Royse Jr.

Theses and Dissertations

The Tongue River-Sentirel Butte contact has been regarded by many workers as a vague color boundary of minor extent within a relatively homogeneous sequence of Paleocene strata. Consequently, the Sentinel Butte has come to be regarded as a subordinate unit of the ”Tongue River Formation. As defined in report, the contact is a distinctive horizon between two discrete lithogenetic units. It characterized by three criteria: a horizon (HT Butte bad) &t the top of the Tongue River sequence; a. basal sandy unit in the Sentinel Butte sequence, and a marked change in color between buff yellow Tongue River sediments below …


A Subsurface Geologic Study Of Petroleum Possibilities In The Pennsylvanian Rocks Of Concho County, Texas, Gregory Paul Kraus Jan 1967

A Subsurface Geologic Study Of Petroleum Possibilities In The Pennsylvanian Rocks Of Concho County, Texas, Gregory Paul Kraus

Masters Theses

"During early Pennsylvanian time the area now occupied by Concho County was a portion of the Texas peninsula, a broad, low arch with a karst topography developing on its exposed Ellenburger surface. A mid-Pennsylvanian marine transgression inundated the arch and it became an area of clear, shallow water deposition favorable to limestone development. Local sedimentation during Strawn time was largely controlled by its position relative to the Llano uplift and surrounding basins. A variety of subsurface maps were constructed for this study essentially utilizing electric log data. The results indicate that limestones of the Strawn platform facies rapidly change in …


Ore Controls And Formation Of The Ore-Bearing Structures In The Idarado Mines, San Miguel And Ouray Counties, Colorado, S. R. Sanjines Jan 1967

Ore Controls And Formation Of The Ore-Bearing Structures In The Idarado Mines, San Miguel And Ouray Counties, Colorado, S. R. Sanjines

Theses and Dissertations

Two major ore-bearing veins were studied on two levels in the Idarado mine, on the northwestern flank of the San Juan Mountains of southwestern Colorado. The Argentine vein, striking N. 10°-20° W. and dipping 75°-85° W., and the Cross vein, striking N. 45°-50° W. and dipping 50° W. represent the two systems to which all productive veins of the mine belong. Although not formed simultaneously, all veins represent mid-Tertiary mineralization associated with volcanism that formed the San Juan Mountains. Vein minerals are galena, sphalerite, chalcopyrite, silver (probably as sulfides), and gold in a gangue of pyrite, quartz, calcite and epidote. …


Geology Of The Acari Iron Mining District Arequipa, Peru, Raul Alejandro Zevallos Jan 1966

Geology Of The Acari Iron Mining District Arequipa, Peru, Raul Alejandro Zevallos

Masters Theses

"The Acari Iron Mining District, part of a tilted uplifted fault block, comprises an area about 300 square kilometers, in the southern part of the coastal belt of Peru. It is in the foothills of the western range of the Andes and it is dominantly formed by granodioritic and granitic intrusive rocks which belong to the Andean batholith of Cretaceous-Tertiary age. The intrusive rocks are overlain by a central, elongated, northwest trending band, of metasedimentary and volcanic rocks

The magnetite deposits of Acari district are long, dike-shaped bodies, which fill two systems of fractures in the granodiorite intrusive, located in …


Precambrian Geology In Humboldt Township, Marquette County, Michigan, Peter D. Rowley Jan 1965

Precambrian Geology In Humboldt Township, Marquette County, Michigan, Peter D. Rowley

Journal of the Minnesota Academy of Science

ABSTRACT-The present study involved investigation of gneissic granite, migmatite, basic dikes, and faults in part of the Southern Complex of Michig.an. The average strike of the foliation of the gneissic granite based upon the orientation of feldspar phenocrysts is N. 60° w·;, the strike of the major dike set is between N. 30° W. and N. 60° W., the average strike of the fault zones-is N. 52° W., and a two-mile long body of migmatite trends about N. 57° W. The known history starts in the early Precambrian, when gneissic granite was emplaced and formed migmatites by incorporation of wall-rock …


Miocene Mammals And Central American Seaways, Frank C. Whitmore Jr., Robert H. Stewart Jan 1965

Miocene Mammals And Central American Seaways, Frank C. Whitmore Jr., Robert H. Stewart

United States Geological Survey: Staff Publications

The fossil mammal faunas of North and South America indicate that the two continents were separated from Paleocene or earlier time until the late Pliocene. Unfortunately our almost complete ignorance of the Tertiary land mammals of Central America, the geology of this large area, makes reconstruction of the Tertiary zoogeography of the region between the continents an exercise involving considerable speculation.


Available Water Supply Of The Las Vegas Ground-Water Basin Nevada, Glenn Thomas Malmberg Jan 1965

Available Water Supply Of The Las Vegas Ground-Water Basin Nevada, Glenn Thomas Malmberg

Publications (WR)

The Las Vegas ground-water basin as described in this report includes the southern part of Indian Spring Valley, Three Lakes Valley, the northern half of Ivanpah Valley, and Las Vegas Valley. These valleys in part are inferred to form a hydrologic unit that includes an area of about 3,000 square miles in the southern part of Clark County, Nev.

The valleys forming the Las Vegas ground-water basin are broad structural depressions surrounded by mountains. The climate of the region is arid, and precipitation in the basin lowlands rarely exceeds 5 inches per year. Drainage is interior except for occasional Hood …


Petrology And Mineralogy Of The "Old Workings Area," El Salvador, Chile, Bertis James Vander Schaaff Jan 1965

Petrology And Mineralogy Of The "Old Workings Area," El Salvador, Chile, Bertis James Vander Schaaff

Masters Theses

"The 'Old Workings Area,' so called for its early mining by the Incas, is located 4 1/2 miles northeast of the El Salvador Porphyry copper deposit, the third largest copper producer in Chile. The area mapped in this study is shown to consist of rhyolite pebble conglomerate, two volcanic flows, andesite and rhyolite porphyry, and two intrusions. Quartz porphyry and tourmaline-bearing breccia. Petrographic study of surface and drill core rock samples confirms the field nomenclature used for the five rock types. All of the rock types are altered, but the quartz porphyry and andesite are the most intensely altered. Both …


Structural And Magnetic Characteristics Of The Belton Anomaly, Cass County, Missouri, Nagib Chamon Jan 1964

Structural And Magnetic Characteristics Of The Belton Anomaly, Cass County, Missouri, Nagib Chamon

Masters Theses

"A vertical intensity magnetic survey of approximately 156 square miles in Cass County, central-west Missouri, revealed a broad circular anomaly whose magnetic relief exceeds 1000 gammas. Surface rocks are very gently inclined and are of Pennsylvanian age. Crystalline basement rocks are at a depth of approximately 2400 feet. Analysis of the data shows that the Belton anomaly consists of discontinuous smaller magnetic anomalies surrounding the central part of this broad anomaly. The central area of the Belton anomaly is occupied by a magnetic low. Analytical calculation showed that the source of the magnetic disturbance is at least 3650 feet below …


Pegmatites Of The Anderson Ridge Quadrangle, Fremont County, Wyoming, Hassan A. Etr Jan 1963

Pegmatites Of The Anderson Ridge Quadrangle, Fremont County, Wyoming, Hassan A. Etr

Masters Theses

“The oldest rocks in the area consist mainly of para- schists of low to medium rank and restricted higher rank sillimanite schist. The entire series has been at least double folded. The most apparent are tight north to north- east trending folds. These have been intruded in the northern part of the area by a batholithic body of granitic composition, a granitic stock, a pegmatitic granite, a granitic sill-like body and different types of pegmatite dikes and sills. The youngest intrusions are a series of northeast trending basic dikes and sills. A major easterly trending transverse fault and a series …


Pleistocene Formations In Indiana, William J. Wayne Jan 1963

Pleistocene Formations In Indiana, William J. Wayne

Department of Earth and Atmospheric Sciences: Faculty Publications

The system of stratigraphic classification used in North America for all sedimentary rock units except nonmarine deposits of the Pleistocene Series established groups, formations, and smaller units based on objectively determined characteristics of the rocks and not on geomorphology or subjective features, such as geologic time. Not all students of the nonmarine Pleistocene have kept these two kinds of units distinct from each other. The Pleistocene sediments of Indiana and the surrounding States are continental in origin rather than marine, and thus they show far less lithologic homogeneity than sediments and rocks of marine origin. Nevertheless, these Pleistocene sediments can …


Stereoradiography As Applied To Problems Of Petrology., Martin Goldstone Jan 1963

Stereoradiography As Applied To Problems Of Petrology., Martin Goldstone

Masters Theses

"Stereoscopic examination of radiographs of rock and ore samples allows a rapid, cursory determination of texture and structure without time consuming preparation and use of thin sections. In addition, volumetric estimates of known mineral components can be made providing they possess significantly different x-ray absorption characteristics.

Stereoscopic effect was most pronounced for specimens having well defined components of structure such as bedding, banding, lineation, inclusions, textural variations and moderate to large x-ray absorption differences. In general, these conditions were best met by ores or ore minerals with their related gangue minerals.

Stereoscopic examination was not successful in revealing twinning or …


Hydrogeology Of Reservoir Sites In The Meramec River Basin, Missouri., John H. Anderson Jan 1963

Hydrogeology Of Reservoir Sites In The Meramec River Basin, Missouri., John H. Anderson

Masters Theses

"Governmental and private agencies have proposed construction of multiple purpose dams in the Meramec River Basin for flood control, conservation, recreation and possible power development. Evaluation of the effects of reservoirs created by these dams on ground water conditions has not been published. Study of possible effects led to the thesis that prediction of changes in ground water conditions could be made.

Several limited applications of ground water geology techniques to the problem of reservoir-ground water relations were studied; no thorough previous studies were found. Apparently, complete studies have not been undertaken by even the larger agencies.

Inspection of the …


Ground Water Investigation In The Southern Half Of Franklin County, Missouri, Kemal Piskin Jan 1962

Ground Water Investigation In The Southern Half Of Franklin County, Missouri, Kemal Piskin

Masters Theses

"Increasing population and industrialization in Franklin County, Missouri, has led to increased demand for water. Much of this demand will be satisfied from ground water resources. Although the general geology of Franklin County has been mentioned in several publications, no detailed study of structure and ground water geology had been done. This thesis consists of study of stratigraphy, lithology, and geologic structure, and analysis of well log data to determine occurrence and availability of ground water, in the southern half of Franklin County.

Stratigraphy and lithology is compiled from previous literature, modified to agree with well log data. Structural geology …


Mineral Paragenesis And Trace Element Distribution In The Tri-State Zinc-Lead District Missouri, Kansas, Oklahoma, Richard D. Hagni Jan 1962

Mineral Paragenesis And Trace Element Distribution In The Tri-State Zinc-Lead District Missouri, Kansas, Oklahoma, Richard D. Hagni

Doctoral Dissertations

"A review of the literature pertaining to the mineral paragenesis and trace element distribution in the Tri-State zinc-lead district of Missouri, Kansas, and Oklahoma revealed inconsistencies in observation and in interpretation and divergent hypotheses regarding the origin of the ores. In an attempt to reconcile the data collected by many investigators over nearly three-quarters of a century, the writer observed working faces in 37 mines, collected over 2,000 specimens for binocular examination and prepared and studied 110 polished surfaces and 60 thin sections of the ores and associated rocks utilizing mineralographic, petrographic, and x-ray techniques. This detailed study resulted in …


Sedimentary Features And Geochemistry Of The Sulphide Facies In The Transition Between The Lamotte Sandstone And The Bonneterre Formation In The Fredericktown Area, Madison County, Missouri, Farouk El Baz Jan 1961

Sedimentary Features And Geochemistry Of The Sulphide Facies In The Transition Between The Lamotte Sandstone And The Bonneterre Formation In The Fredericktown Area, Madison County, Missouri, Farouk El Baz

Masters Theses

"SCOPE AND PURPOSE The Lead Belt area of southeast Missouri, which is nearly 40 km. long and 10 km. wide, is considered, at the present time, the most important lead district in the world. Lead has been mined in this area by the natives prior to 1720, and almost continuously up to the present day. A variety of sulphides are mined from different places in the district.

The sulphide deposits in the Lead Belt are considered to be typical examples of the Mississippi Valley Type Deposits, which are distributed all over the world. As in practically all the Mississippi Valley …


Geology Of The Upper Middle Creek Area Huerfano County, Colorado, J. H. Copeland May 1959

Geology Of The Upper Middle Creek Area Huerfano County, Colorado, J. H. Copeland

Open Access Master's Theses (through 2010)

The Sangre de Cristo Mountains of Colorado and New Mexico are, geologically speaking, relatively unknown. The equivocal nature of our knowledge of the range was a primary reason for studying a portion of it in some detail. Most of the previous studies have been concerned with the northern part of the range in Colorado, in the general area between Salida and La Veta Pass. This work has indicated that the complicated structure which characterizes the northern part of the range becomes simpler to the south. Therefore, a second objective of the current study has been to test this hypothesis. Thirdly, …


Detection Of Buried Basement Highs By Airphoto Drainage Pattern Analysis, Reynolds And Wayne Counties, Missouri, Papken Aram Zarzavatjian Jan 1958

Detection Of Buried Basement Highs By Airphoto Drainage Pattern Analysis, Reynolds And Wayne Counties, Missouri, Papken Aram Zarzavatjian

Masters Theses

"Purpose and Scope: The purpose of this study is to determine if it is possible to detect buried Precambrian igneous hills in Wayne County and the larger part of Reynolds County in southeast Missouri by the use of aerial photo drainage pattern analysis.

The St. Francis Mountains are located in southeast Missouri. They form a part of the Precambrian basement complex, and have been exposed at the surface by the erosion of the lower Paleozoic sediments which covered them. Some of the hills which make up the St. Francis Mountains are exposed to a great degree, while others still have …


Medial Pleistocene Fossil Vertebrate Localities In Nebraska, C. Bertrand Schultz, Lloyd G. Tanner Jan 1957

Medial Pleistocene Fossil Vertebrate Localities In Nebraska, C. Bertrand Schultz, Lloyd G. Tanner

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

The accurate geologic dating of Pleistocene vertebrate localities which occur outside the glaciated regions has always been difficult. Several new fossil localities in Nebraska now provide data for a better understanding of the paleoecology and faunal evidence of the medial Pleistocene of the Great Plains region.

A fossil quarry, containing the remains of both vertebrates and invertebrates, has been discovered in south-central Nebraska (11/2 miles south and west of Angus in Nuckolls County). The fossils are preserved in Sappa silts in a lime concentration zone (C horizon) of a Yarmouth paleosol. The calcium carbonate appears to have been responsible for …


A Geological Study Of The Irvine Ranch Area, Johnson And Campbell Counties, Wyoming, Gale E. Butterfield Jan 1957

A Geological Study Of The Irvine Ranch Area, Johnson And Campbell Counties, Wyoming, Gale E. Butterfield

Masters Theses

"The discovery of uranium in the Powder River Basin, Wyoming, by the U. S. Geological Survey in 1952 has lead to an extensive exploration program throughout the region by both private and governmental agencies. This report is a geological study of an area in the southwestern part of the basin.

Geological and radiometric mapping carried out as a part of this report indicated several areas of uranium occurrence. Some of these occurrences warrant tests by drilling.

Mineralogical and petrographic study has shown the principal uranium minerals to be carnotite and metatyuyamunite. The mineralization occurs in arkosic sandstones. Assays of the …


Geochemical Exploration For Hidden Ore Deposits, D. H. Yardley May 1956

Geochemical Exploration For Hidden Ore Deposits, D. H. Yardley

Journal of the Minnesota Academy of Science

No abstract provided.


The Spotted Horse Coal Field, Sheridan And Campbell Counties, Wyoming., Wilds W. Olive Jan 1953

The Spotted Horse Coal Field, Sheridan And Campbell Counties, Wyoming., Wilds W. Olive

LSU Historical Dissertations and Theses

No abstract provided.


Mineralogy Of The Silver King Mine Of Park City, Utah, Pierce D. Parker May 1951

Mineralogy Of The Silver King Mine Of Park City, Utah, Pierce D. Parker

Bachelors Theses and Reports, 1928 - 1970

Except for the early work of Boutwell and Irving, little has been published on the geology of the Park City mining district. For this reason and because of the availability of a selected suite of ores from the Silver King mine of this area, this writer chose the mineralogy of the Silver King mine as a senior thesis for the de­partment of Geology of the Montana School of Mines.


Studies Of Antimony Occurrence With Special Relation To Its Effective Extraction, San Jose Antimony Mines, Wadley, San Luis Potosi, Mexico, J. C. Archibald Jr. Jan 1951

Studies Of Antimony Occurrence With Special Relation To Its Effective Extraction, San Jose Antimony Mines, Wadley, San Luis Potosi, Mexico, J. C. Archibald Jr.

Bachelors Theses and Reports, 1928 - 1970

The mines at San Jose which are within the Wadley unit are the largest antimony mines in Mexico. These mines produce more than half of the antimony produced by the company from its mining operations. Since the time of the author's connection with the company, a number of changes have been made in planning of development work, handling of labor, methods of mine development, cost improvement, and other problems inherent in the successful guidance of an operation.


Physiographic Surfaces And Weathering Near Butte, Gordon B. Brox May 1950

Physiographic Surfaces And Weathering Near Butte, Gordon B. Brox

Bachelors Theses and Reports, 1928 - 1970

Three cycles of erosion have modified the Boulder batholith. The earliest cycle produced a peneplaination that has been largely obliterated by a partially completed intermediate cycle, and the recent cycle now in progress.


Geology And Geological Structure Of The Alberta And Saskatchewan Plains, William E. Topley Jun 1948

Geology And Geological Structure Of The Alberta And Saskatchewan Plains, William E. Topley

Bachelors Theses and Reports, 1928 - 1970

Alberta, responsible for ninety per cent of Canada's output, had, by 1947 entered into her fifth year of production decline. Only ten per cent of Canada's oil requirements were secured from home fields. Ninety per cent had to be imported, mainly from the United States. How long could imports be maintained on present levels? During the year, the United States had started rationing; in one sector of its domain. Would this become general? If so, what was the answer for Canada?


Geology And Ore Deposits Of The Salt Chuck-Rush And Brown Mine Area Prince Of Wales Island, Alaska, Judson H. Whitman May 1948

Geology And Ore Deposits Of The Salt Chuck-Rush And Brown Mine Area Prince Of Wales Island, Alaska, Judson H. Whitman

Bachelors Theses and Reports, 1928 - 1970

The Salt Chuck, Rush and Brown, and adjacent mines and claims form an area of approximately 15 square miles near the head of Kasaan Bay about 10 miles northwest of the village of Kasaan on Prince of Wales Island in southeastern Alaska. It is an area of moderate relief in which the hills rise from the water’s edge to heights of some 500 feet. Most of the area is covered with dense vegetation and muskeg.


Geological Studies In Utah, J. Stewart Williams Apr 1948

Geological Studies In Utah, J. Stewart Williams

Faculty Honor Lectures

Utah's thousands of square miles of mountains, plateaus, and i ~ desert basins exhibit a wide variety of geological features and offer the student of geology an endless series of challenging problems. The solution of some of these problems began nearly one hundred years ago with the surveys of the United States territories; the work continues today at a greatly accelerated rate with scores of professional geologists and advanced students in the field each summer. The writer and students under his direction have made some contributions to the solution of a few of these problems in the twelve years that …