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Paleozoic-Mesozoic Boundary in the Berry Creek Quadrangle, Northwestern Sierra Nevada, California

Description: Abstract: Structural and petrologic studies in the Berry Creek quadrangle at the north end of the western metamorphic belt of the Sierra Nevada have yielded new information that helps in distinguishing between the chemically similar Paleozoic and Mesozoic rocks. The distinguishing features are structural and textural and result from different degrees of deformation. Most Paleozoic rocks are strongly deformed and thoroughly recrystallized. Phenocrysts in metavolcanic rocks are granulated and dra… more
Date: 1977
Creator: Hietanen, Anna Martta
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Stratigraphy and Geologic History of the Montana Group and Equivalent Rocks, Montana, Wyoming, and North and South Dakota

Description: From introduction: This is a progress report on regional stratigraphic and paleontologic studies of the Upper Cretaceous Montana Group and equivalent rocks in the northern part of the western interior of the United States. It presents preliminary data on the positions of strandlines during a 14-m.y. (million year) span of the Late Cretaceous as well as our interpretations of the geologic history of this period.
Date: 1973
Creator: Gill, James R. & Cobban, William Aubrey
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Report on Progress of Investigations of Mineral Resources of Alaska in 1904

Description: From letter of transmittal: The report contains fourteen papers, prepared by ten members of the geologic corps, who have been engaged in Alaskan investigations during the last year. In this report an attempt has been made to summarize the economic results of last season's field work. Geologic matter has been entirely excluded, except where it has a direct bearing on the subjects under discussion. While such a report can have no permanent value, other than as a record of mining conditions during… more
Date: 1905
Creator: Brooks, Alfred H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Contributions to Economic Geology: 1904

Description: From letter of transmittal: The report contains 63 contributions from 37 members of the Survey who have been engaged more or less continuously throughout the year in economic work, together with brief statements by the geologists in charge of the section of metalliferous ores and the section of nonmetalliferous economic minerals, of the extent and character of the economic work being carried on in the Survey.
Date: 1905
Creator: Emmons, Samuel Franklin & Hayes, C. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Kevin-Sunburst Oil Field and Other Possibilities of Oil and Gas in the Sweetgrass Arch, Montana

Description: From introduction: The discovery of oil near Kevin, Mont., in March, 1922, gave prominence to the Sweetgrass arch, which is a large structural uplift somewhat similar in size and degree of folding to the Cincinnati arch. Most of the development so far attempted on this fold has been on the Kevin-Sunburst dome, a bulge upon the crest of the arch just south of the Canadian boundary. The dome covers about 16 townships, is nearly circular in outline, and has very low dips away from its highest poin… more
Date: 1929
Creator: Collier, Arthur J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Environmental Geochemical Studies of Selected Mineral Deposits in Wrangell-St. Elias National Park and Preserve, Alaska

Description: From abstract: Environmental geochemical investigations took place in Wrangell-St. Elias National Park and Preserve (WRST), Alaska, between 1994 and 1997. Areas studied include the historic Kennecott stratabound copper mines and mill area; the historic mines and mill in the Bremner district, where gold was produced from polymetallic veins; the sporadically active gold placer mines at Gold Hill; the undisturbed, unmined porphyry copper-molybdenum deposits at Orange Hill and Bond Creek; and the h… more
Date: 2000
Creator: Eppinger, Robert G.; Briggs, Paul H.; Rosenkrans, Danny S. & Ballestrazze, Vanessa
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Lyon Station-Paulins Kill Nappe : the Frontal Structure of the Musconetcong Nappe System in Eastern Pennsylvania and New Jersey

Description: From abstract: Geologic and aeromagnetic data show that a major tectonic unit underlies rocks of the Musconetcong nappe in the Great Valley of eastern Pennsylvania and New Jersey. This structure, the Lyon Station-Paulins Kill nappe, can be traced from Lyon Station, Pa., at least to Branchville, N.J., a distance of about 120 km. The nappe has a core of Precambrian crystalline rocks as shown by an aeromagnetic anomaly that has the same signature as the outcropping Precambrian rocks of the Muscone… more
Date: 1978
Creator: Drake, Avery Ala, Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Revisions of Ulmus and Zelkova in the Middle and Late Tertiary of Western North America

Description: Abstract: Examination of previously described and some undescribed leaves of Ulmus and Zelkova from the later Oligocene, Miocene, and Pliocene of western North America indicates that at least eight species of Ulmus and two species of Zelkova are represented. Three new species are described: Ulmus chaneyi, U. knowltoni, and Zelkova browni.
Date: 1977
Creator: Tanai, Toshimasa & Wolfe, Jack A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Manganiferous and Ferruginous Chert in Perry and Lewis Counties, Tennessee

Description: From abstract: Perry and Lewis Counties, east of the Tennessee River, in west-middle Tennessee, are underlain by nearly flat-lying rocks of Paleozoic age, with Mississippian cherty limestones forming the greater part of the surface of the western Highland Rim Plateau ridges. Near the summits of the ridges there is a fairly definite horizon in the chert that contains manganese and iron oxides in varying degrees of concentration. Weathering of the mineralized chert has produced widespread float o… more
Date: 1943
Creator: Burchard, Ernest F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Geology and Petrography of Crater Lake National Park

Description: From introduction: The two papers published here refer practically to the whole region included in the National Park. The one. Part I, treats primarily of the geology, the development of the great volcano, Mount Mazama, and its collapse, which gave birth to Crater Lake; the other, Part II, deals with the petrography, and gives a special description of the various rocks occurring in the park.
Date: 1902
Creator: Diller, Joseph Silas & Patton, Horace Bushnell
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Sorting and Deposition of Allochthonous Plant Material in a Modern Environment at Silwood Lake, Silwood Park, Berkshire, England

Description: Abstract: Quantitative statistical sampling of plant debris entombed within deltaic sediments of a Holocene fluviolacustrine environment at Silwood Lake, Berkshire, demonstrates that patterns of deposition exist that can be used to reconstruct the relative spatial distributions of species within the source vegetation.
Date: 1981
Creator: Spicer, Robert A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Some Quicksilver Prospects in Adjacent Parts of Nevada, California, and Oregon

Description: Abstract: This report summarizes the results of reconnaissance study of quicksilver deposits in the northwestern corner of Nevada, the northeastern corner of California, and Lake County, Oreg. made in August 1940. The Lene Pine district, Nevada, the Silvertown and Red Hawk properties in California, and the Currier and Glass Butte properties in Oregon were included. The first two of these require further development before a definite opinion as to their value can be formed. The Red Hawk mine ha… more
Date: 1941
Creator: Ross, Clyde P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Mineralogy and Stratigraphy of the Lower Part of the Pierre Shale, South Dakota and Nebraska

Description: From abstract and introduction: Mineralogic and stratigraphic studies of the lower part of the Pierre Shale of Late Cretaceous age along the Missouri River indicate correlations different from those generally accepted. The purposes of this paper are to present evidence for the new correlations and to resolve problems of formal nomenclature that result from them.
Date: 1965
Creator: Schultz, Leonard Gene
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Mica-Bearing Pegmatites of New Hampshire: a Preliminary Report

Description: From abstract: Mica has been mined in New Hampshire since 1803. Production from 1908 through 1939 has aggregated 13,326,990 pounds of sheet and punch mica, an annual average of 416,470 pounds. Since 1931 production has been below this average, because of economic conditions rather than depletions. The mica-bearing pegmatites of the Grafton and Keene districts occur mostly in sillimanite-mica schist adjacent to large areas of biotite gneiss. The pegmatite bodies range from a fraction of an inch … more
Date: 1942
Creator: Olson, J. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Research in the Geysers-Clear Lake Geothermal Area, Northern California

Description: From abstract: The Geysers-Clear Lake geothermal area lies within the central belt of the Franciscan assemblage in northern California. The structure of this terrane is characterized by northeast-dipping imbricate thrust slices that have been warped and cut by steeply dipping strike-slip and normal faults. Introduction of magma into the crust beneath the Geysers-Clear Lake area can be related to eastsoutheast extension accompanying northward propagation of the San Andreas transform system betwe… more
Date: 1981
Creator: McLaughlin, Robert J. & Donnelly-Nolan, Julie M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Spectrographic Analysis of Plasmajets: Progress Report 2

Description: Abstract: This is the second progress report on the work performed at Sandia Corporation in the use of spectrographic techniques in plasmajet diagnostics. Typical results of spectrographic data from argon and nitrogen plasmajets are included. For the argon jet, the results from line intensity measurements of ionized and unionized atoms generally give good information. However, results from hydrogen line broadening measurements indicate several unexplained discrepancies. For the nitrogen jet, th… more
Date: March 1963
Creator: Shipley, K. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Studies Related to the Charleston, South Carolina, Earthquake of 1886: a Preliminary Report

Description: From abstract: The seismic history of the southeastern United States is dominated by the 1886 earthquake near Charleston, S.C. An understanding of the specific source and the uniqueness of the neotectonic setting of this large earthquake is essential in order to properly assess seismic hazards in the southeastern United States. Such knowledge will also contribute to the fundamental understanding of intraplate earthquakes and will aid indirectly in deciphering the evolution of Atlantic-type cont… more
Date: 1977
Creator: Rankin, Douglas W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Geology of the Portage Pass Area, Alaska

Description: Abstract: The Portage Pass area is in south-central Alaska, and includes part of the narrow neck of land that joins the Kenai Peninsula with the mainland to the north. This region is in general mountainous, elevations ranging from sea level to more than 4,000 feet on the peaks bordering the area. Several glaciers, all of which are apparently receding, extend into the area. Vegetation, chiefly alder and cottonwood on the valley lowlands and some spruce and hemlock on the lower slopes, extends to… more
Date: 1943
Creator: Barnes, Farrell F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Geology of the Mount McKinley Quadrangle, Alaska

Description: From abstract: The Mount McKinley quadrangle, in south-central Alaska, includes parts of the Alaska Range, the Tanana and Kuskokwim lowlands, and the Kuskokwim Mountains. Schists of Precambrian age crop out in the northern foothills of the Alaska Range. Sedimentary and volcanic rocks of Paleozoic and Mesozoic age are exposed in the Kuskokwim Mountains, where little is known of their distribution and character, and in the Alaska Range, where they occupy the axial part and northern limb of a grea… more
Date: 1961
Creator: Reed, John Calvin, Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Geology of the Craig Quadrangle, Alaska

Description: From abstract: The Craig quadrangle, in southeastern Alaska, lies entirely within the Tongass National Forest and includes a large part of Prince of Wales Island, the largest island of the Alexander Archipelago. Sedimentary, volcanic, and metamorphic rocks of Paleozoic and Mesozoic age are exposed as complexly folded and faulted sequences. Paleozoic rocks occupy a broad geanticlinal area comprising Prince of Wales Island and the islands to the west. Metamorphosed Mesozoic rocks form a geosyncli… more
Date: 1961
Creator: Condon, W. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Geology of the North Bradfield River Iron Prospect, Southeastern Alaska

Description: From abstract: The North Bradfield River iron prospect is in southeastern Alaska in rugged terrain about 8 miles southwest of the Canadian boundary and about 15 miles northeast of the head of Bradfield Canal. The prospect includes several magnetite-rich ore bodies of pyrometasomatic origin that are localized in skarn. The skarn forms a small part of a northwestward-trending roof pendant that is enclosed in the composite Coast Range batholith. The dominant rocks of the roof pendant are gneiss, … more
Date: 1963
Creator: MacKevett, E. M., Jr. & Blake, M. Clark, Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Geology of the Sumdum Copper-Zinc Prospect, Southeastern Alaska

Description: From abstract: The Sumdum copper-zinc prospect is in an alpine region on the mainland of southeastern Alaska, about 50 miles southeast of Juneau and about 25 miles west of the Canadian boundary. The ore-bearing outcrops at the prospect were discovered by the Alaska Helicopter Syndicate during the summer of 1958. The prospect is within a few thousand feet of the western margin of the . Coast Range batholith in regionally metamorphosed rocks that locally -have -been contact: metamorphosed. Most o… more
Date: 1964
Creator: MacKevett, E. M., Jr. & Blake, M. Clark, Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Uranophane at Silver Cliff Mine, Lusk, Wyoming

Description: Abstract: The uranium deposit at the Silver Cliff mine near Lusk, Wyo., consists primarily of uranophane which occurs as fracture fillings and small replacement pockets in faulted and fractured calcareous sandstone of Cambrian(?) age. The country rock in the vicinity of the mine is schist of pre-Cambrian age intruded by pegmatite dikes and is unconformably overlain by almost horizontal sandstone of Cambrian(?) age. The mine is on the southern end of the Lusk Dome, a local structure probably rel… more
Date: 1954
Creator: Wilmarth, Verl R. & Johnson, Donald H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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