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Periodic Heat Flow in a Stratified Medium with Application to Permafrost Problems

Description: From abstract: Solutions to the Fourier heat equation for quasi-steady periodic flow in a stratified semi-infinite medium can be obtained readily by standard methods. The results have wide application to studies of earth-temperature variations induced by diurnal, annual, and other periodic variations in ground-surface temperature. Much of the previous work on this subject has been interpreted with reference to the solution for the homogeneous case; and this can be seriously in error when applie… more
Date: 1959
Creator: Lachenbruch, Arthur H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Oxidized Zinc Deposits of the United States: Part 3. Colorado

Description: From abstract: Deposits of oxidized zinc ore are widely distributed in the western part of Colorado in the Rocky Mountains west of the Front Range and in the uplifted plateaus that border the main area of the Colorado Plateau. The principal production and reserves are restricted to several mining districts--Leadville. Aspen, Monarch, Spring Creek. Horseshoe, Tomichi, Tincup, and Rico--in all of which limestone and dolomites of Paleozoic age are the main host rocks. One deposit, that of the Seda… more
Date: 1964
Creator: Heyl, Allen V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Ancient Lavas in Shenandoah National Park Near Luray, Virginia

Description: Abstract: In the Blue Ridge Province of northern Virginia, Maryland, and southern Pennsylvania, Lower Cambrian beds are underlain by a thick sequence of greenstone and interbedded sedimentary rocks known as the Catoctin Formation. An area near Luray, Va., was studied to determine the thickness of the formation, its relationship to overlying and underlying rocks, and the original nature of the lavas from which the Catoctin greenstone was derived. There the Catoctin Formation lies unconformably … more
Date: 1969
Creator: Reed, John Calvin, Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Pecos National Monument, New Mexico: Its Geologic Setting

Description: From introduction: The ruins of the pueblos and missions of Pecos lie on the east bank of Glorieta Creek near its junction with the Pecos River at the south end of the Sangre de Cristo Mountains in north-central New Mexico. Here the Pecos River and Glorieta Creek have formed a broad rolling valley in which the red adobe walls of the mission church stand as a striking monument to a historic past.
Date: 1969
Creator: Johnson, Ross B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Gold Veins Near Great Falls, Maryland

Description: From abstract: Small deposits of native gold are present along an anastomosing system of quartz veins and shear zones just east of Great Falls, Montgomery County, Md. The deposits were discovered in 1861 and were worked sporadically until 1951, yielding more than 5,000 ounces of gold. The vein system and the principal veins within it strike a few degrees west of north, at an appreciable angle to foliation and fold axial planes in enclosing rocks of the Wissahickon Formation of late Precambrian … more
Date: 1969
Creator: Reed, John Calvin, Jr. & Reed, John Calvin
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Surficial Geology of Mount Rainier National Park, Washington

Description: From introduction: Much of the ground surface around Mount Rainier volcano is directly underlain by loose geologic deposits that veneer the hard rock formations. Examples of these deposits are sand and gravel bars along the rivers, ridges of loose rock debris beside the glaciers, and sloping aprons of rock fragments beneath almost every cliff. Even though they are generally thin and inconspicuous when compared with the rock formations, these surficial deposits are clues to geologic events that.… more
Date: 1969
Creator: Crandell, Dwight Raymond
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Geology and Mineral Resources of the Northern Part of the North Cascades National Park, Washington

Description: Introduction: This report was started as part of a study of the North Cascade Primitive Area, an area of about 830,000 acres, which adjoined the Canadian border on the north and which extended from Mount Shuksan on the west to Rock Mountain on the east. In the fall of 1968, Public Law 90-544, 90th Cong., reclassified the North Cascade Primitive Area and certain other national forest lands and created the North Cascades National Park, the Ross Lake National Recreation Area, and the Pasayten Wild… more
Date: 1972
Creator: Staatz, Mortimer Hay; Tabor, Rowland W.; Weis, Paul L.; Robertson, Jacques F.; Van Noy, Ronald M. & Pattee, Eldon C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Silurian, Devonian, and Mississippian Formations of the Funeral Mountains in the Ryan Quadrangle, Death Valley Region, California

Description: From abstract: A composite section of the Silurian, Devonian, and Mississippian formations in the Funeral Mountains between Death Valley and Amargosa Valley is about 4,700 feet thick. The formations are in the top of a concordant, complexly faulted sequence that is about 25,000 feet thick from the highest part of the Precambrian to the Upper Mississippian. The Silurian and younger formations consist of marine dolomite and limestone that contain some regionally characteristic cherty and siliceou… more
Date: 1974
Creator: McAllister, James Franklin
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Stratigraphic Nomenclature of the Central Santa Monica Mountains, Los Angeles County, California

Description: From abstract: The stratigraphic nomenclature of the central Santa Monica Mountains is revised to conform with present knowledge of the age, distribution, and stratigraphic relations of about 35 bedrock units. The revision is based on 1:12,000-scale mapping of the entire stratigraphic sequence and its facies, the position and stage assignment of abundant fossils, and contact relations.
Date: June 16, 1979
Creator: Yerkes, R. F. & Campbell, Russell H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Geology and Ore Deposits of Northwestern Chichagof Island, Alaska

Description: From introduction: The area of this report is in the northern part of southeastern Alaska (fig. 39). It includes about 400 square miles on northwestern Chichagof Island, latitude 5747' to 58*15' N. and longitude 135 57' to 136 35' W. It is covered by U. S. Geological Survey Mount Fairweather A-1, A-2, and Sitka D--7 and D-8 topographic quadrangle maps. The writer's geologic investigation was started in 1946 as a continuation of earlier work on the west coast of Chichagof Island by J. C. Reed an… more
Date: 1959
Creator: Rossman, Darwin Lucian
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Geology and Coal Resources of the Homer District, Kenai Coal Field, Alaska

Description: From abstract: The Homer district of the Kenai coal field is about 100 miles southwest of Anchorage, in south-central Alaska. It covers an area of about 1,100 square miles on the west side of the Kenai Peninsula, between Tustumena Lake and Kachemak Bay. The principal settlement is Homer, at the southern end of the district, which is connected by the gravel-surfaced Sterling Highway with the Alaska highway system and The Alaska Railroad, and is also served by ocean transportation and one airline. more
Date: 1959
Creator: Barnes, Farrell F. & Cobb, Edward H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Geology of the Mount Katmai Area, Alaska

Description: From abstract: The Mount Katmai area is on the Alaska Peninsula and comprises the Mount Katmai quadrangle, the Cape Douglas area of the adjoining Afognak quadrangle, and parts of the Karluk and Naknek quadrangles. The area, which includes nearly all the Katmai National Monument, is one of high relief and is drained by streams of preglacial origin. At least two ice advances are indicated by the moraine configuration. Present-day glaciation is restricted to numerous alpine glaciers in the mountai… more
Date: 1959
Creator: Keller, A. Samuel & Reiser, Hillard N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Geology of the Jewel Cave Southwest Quadrangle, Custer County, South Dakota

Description: From introduction: This study was part of the U.S. Geological Survey's continuing study of the geology and ore deposits of the southern Black Hills, which was stimulated by the discovery of uranium deposits in sandstone in the area in 1951 (Page and Redden, 1952; Bell and Bales, 1955).
Date: 1963
Creator: Braddock, William A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Radioactive Rare-Earth Deposit at Scrub Oaks Mine, Morris County, New Jersey

Description: From abstract: A deposit of rare-earth minerals in the Scrub Oaks iron mine, Morris County, N. J., was mapped and sampled in 1955. The rare-earth minerals are mainly in coarse-grained magnetite ore and in pegmatite adjacent to it. Discrete bodies of rare-earth-bearing magnetite ore apparently follow the plunge of the main magnetite ore body at the north end of the mine. Radioactivity of the ore containing rare earths is about 0.2 to 0.6 milliroentgens per hour.
Date: 1959
Creator: Klemic, Harry; Heyl, Allen V., Jr.; Taylor, A. R. & Stone, Jerome
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Beryl-bearing Pegmatites in the Ruby Mountains and Other Areas in Nevada and Northwestern Arizona

Description: From abstract: Pegmatite occurs widely in Nevada and northwestern Arizona, but little mining has been done for such pegmatite minerals as mica, feldspar, beryl, and lepidolite. Reconnaissance for beryl-bearing pegmatite in Nevada and in part of Mohave County, Ariz., and detailed studies in the Dawley Canyon area, Elko County, Nev., have shown that beryl occurs in at least 11 districts in the region. Muscovite has been prospected or mined in the Ruby and Virgin Mountains, Nev., and in Mohave Cou… more
Date: 1960
Creator: Olson, Jerry C. & Hinrichs, E. Neal
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Strategic Graphite, A Survey

Description: From abstract: Strategic graphite consists of certain grades of lump and flake graphite for which the United States is largely or entirely dependent on sources abroad. Lump graphite of high purity, necessary in the manufacture of carbon brushes, is imported from Ceylon, where it occurs in vein deposits. Flake graphite, obtained from deposits consisting of graphite disseminated in schists and other metamorphic rocks, is an essential ingredient of crucibles used in the nonferrous metal industries… more
Date: 1960
Creator: Cameron, Eugene N. & Weis, Paul L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Geology and Fluorspar Deposits, Northgate District, Colorado

Description: From abstract: The fluorspar deposits in the Northgate district, Jackson County, Colo., are among the largest in Western United States. The mines were operated intermittently during the 1920's and again during World War II, but production during these early periods of operation was not large. Mining was begun on a larger scale in 1951, and the district has assumed a prominent position among the fluorspar producers in the United States. Within the Northgate district, Precambrian metamorphic and … more
Date: 1960
Creator: Steven, Thomas August
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Areal Geology of the Little Cone Quadrangle, Colorado

Description: From abstract: The Little Cone quadrangle includes an area of about 59 square miles in eastern San Miguel County in southwestern Colorado. The quadrangle contains features characteristic of both the Colorado Plateaus physiographic province and the San Juan Mountains, and it has been affected by geologic events and processes of two different geologic environments.
Date: 1960
Creator: Bush, Alfred Lerner; Marsh, Owen Thayer & Taylor, Richard B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Manganese Deposits in the Drum Mountains, Juab and Millard Counties, Utah

Description: From abstract: The Drum Mountains are in west-central Utah 30 miles northwest of Delta, between the Sevier Desert on the east and Whirlwind Valley on the west. It is a typically barren desert range comprising a westward-tilted structural unit in which is exposed as much as 9,000 feet of quartzite (Cambrian and Precambrian?) and 3,000 feet of carbonate rocks of Cambrian age. These beds, which strike northward and dip west, are cut by myriad east- to northeast trending faults with displacements o… more
Date: 1961
Creator: Crittenden, Max D., Jr.; Straczek, John A. & Roberts, Ralph Jackson
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Geology and Mineral Deposits of the St. Regis-Superior Area, Mineral County, Montana

Description: From introduction: The St. Regis-Superior area was studied during the summers of 1953 and 1954 as a part of geologic investigations by the U.S. Geologic Survey in and near the Coeur d'Alene district. The object of the present work was primarily threefold: to ascertain the main structural features in the area, with particular attention to the Osburn fault zone; to investigate the mineral deposits; and to determine the stratigraphic relations of the rocks.
Date: 1960
Creator: Campbell, Arthur Byron
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Preliminary Report on the Geology and Water Resources of Central Oregon

Description: From introduction: The observations recorded in this paper were made during a rapid reconnaissance from east to west through the central part of Oregon in the summer of 1903, and are in continuation of similar work in the same general region previously done by the author, reports concerning which have been published.
Date: 1905
Creator: Russell, Israel C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Chromite Deposits in Central Part Stillwater Complex, Sweet Grass County, Montana

Description: From abstract: The chromite deposits of the central part of the Stillwater complex lie in a belt 9 miles long between the valleys of Boulder River and the West Fork of the Stillwater River in Sweet Grass County, Mont. The chromite occurs as layers near the middle part of the ultramafic zone in the lower part of the complex. The layers, originally horizontal, have been tilted so that they dip northeastwards at angles ranging from nearly horizontal to nearly vertical, and are cut by many cross fa… more
Date: 1955
Creator: Howland, A. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Strippable lignite Deposits, Slope and Bowman Counties, North Dakota

Description: From abstract: Slope and Bowman Counties, N. Dak., include an area of about 2,450 square miles in the southeastern part of the Fort Union coal region of North Dakota, South Dakota, and Montana. In anticipation of a future increase in the demand for the low-rank coal of this region as a fuel for electric power plants and as a raw material for various chemical synthesizing processes, Slope and Bowman Counties were investigated for deposits of lignite that could be mined by large scale strip minin… more
Date: 1955
Creator: Kepferle, Roy Clark & Culbertson, William C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Geology and Coal Resources of the Henryetta Mining District, Okmulgee County, Oklahoma

Description: From abstract: The mapped area of the Henryetta mining district includes about 168 square miles in Okmulgee County in the east-central part of Oklahoma. The rocks in this district consist of sandstone, silty shale, and shale, and are divided into the Senora formation and the overlying Calvin sandstone of Pennsylvanian age.
Date: 1955
Creator: Dunham, R. J. & Trumbull, J. V. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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