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The Gabbros and Associated Hornblende Rocks Occurring in the Neighborhood of Baltimore, Maryland

Description: From introduction: The present paper is intended as a contribution to our knowledge of a particular phase of metamorphism in eruptive rocks, i.e., that one which is dependent on the secondary development of hornblende by the paramorphism or pseudomorphism of pyroxene.
Date: 1886
Creator: Williams, George Huntington
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.
Partner: UNT Libraries Government Documents Department
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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.
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.
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.
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
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
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.
Partner: UNT Libraries Government Documents Department
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Geology of Devils Tower National Monument, Wyoming

Description: From abstract: Devils Tower is a steep-sided mass of igneous rock that rises above the surrounding hills and the valley of the Belle Fourche River in Crook County, Wyo. It is composed of a crystalline rock, classified as phonolite porphyry, that when fresh is gray but which weathers to green or brown. Vertical joints divide the rock mass into polygonal columns that extend from just above the base to the top of the Tower.
Date: 1956
Creator: Robinson, Charles Sherwood
Partner: UNT Libraries Government Documents Department
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Past Placer-Gold Production from Alaska

Description: "To the end of 1930 Alaska, according to the records of the Geological Survey, had produced placer gold to the value of $258,962,000 from mines widely scattered throughout its length and breadth. The distribution of the placers from which the gold was recovered has been stated in more or less detail in the annual summaries published by the Geological Survey on the mineral industry of Alaska and also in its more complete reports on many of the individual mining districts. Although these summarie… more
Date: 1933
Creator: Smith, Philip S.
Partner: UNT Libraries Government Documents Department
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The Curry District, Alaska

Description: From abstract: The Curry district lies on the south flank of the Alaska Range, on the southeast side of Mount McKinley. Most of it is west of the Alaska Railroad. The eastern portion can be easily reached from several points along the railroad route, but the western portion is much more difficult of access, owing to the numerous glacial streams and the rugged topography. The relief of the area is great, the elevation ranging from 500 feet along the Chulitna River to 20,300 feet at Mount McKinle… more
Date: 1934
Creator: Tuck, Ralph
Partner: UNT Libraries Government Documents Department
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Notes on the Geology of the Alaska Peninsula and the Aleutian Islands

Description: Abstract: During the spring of 1932 an opportunity was offered by the United States Navy for a geologist to accompany an expedition organized to make a reconnaissance of the western part of Alaska Peninsula and the Aleutian Islands. This expedition visited several localities the geology of which was little known. It was found, as had already been expected, that the islands west of Unimak Pass are composed mainly of basic volcanic lavas and fragmental materials, into which have later been inject… more
Date: 1934
Creator: Capps, Stephen R.
Partner: UNT Libraries Government Documents Department
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Geology of the Santa Rita Mining Area, New Mexico

Description: From abstract: The Santa Rita mining area (pl. 1), covering 35 square miles of semiarid mountainous land, lies within the Silver City 30-minute quadrangle, Grant County, N. Mex., and includes the most productive part of the Central or Hanover mining district. Ore was produced in this district as early as 1804 and production continued intermittently for a century before the developments were undertaken that led to large-scale copper mining, which began in 1912. The output of zinc, lead, and iron… more
Date: 1935
Creator: Spencer, Arthur C. & Paige, Sidney
Partner: UNT Libraries Government Documents Department
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Lode Deposits of Eureka and Vicinity, Kantishna District, Alaska

Description: From abstract: The Kantishna mining district is about 90 miles west of McKinley Park station on the Alaska Railroad. The part of the district covered by this report comprises an area of about 72 square miles in the form of a strip 6 miles wide and 13 miles long. The bedrock is mainly a metamorphic series of rocks which within the area has been differentiated into a quartz-muscovite schist and a calcareous faces that ranges from limestone to chlorite schist. A few small dikes of quartz porphyry … more
Date: 1933
Creator: Wells, Francis G.
Partner: UNT Libraries Government Documents Department
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The Contact Mining District, Nevada

Description: From abstract: This report summarizes the results of a reexamination, in 1930, of the Contact mining district, in Elko County, northern Nevada. A report published as a result of a visit in 1910 summarizes the major features of the geology of the district, and the principal new data in the present paper pertain to mining development occasioned by the completion of a railroad through the camp in 1925.
Date: 1935
Creator: Schrader, Frank C.
Partner: UNT Libraries Government Documents Department
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Coal Geology of the White Oak Quadrangle, Magoffin and Morgan Counties, Kentucky

Description: From abstract: The White Oak quadrangle lies near the western edge of the eastern Kentucky coalfield and includes approximately 59 square miles of parts of Magoffin and Morgan Counties, Ky. The outcropping rocks are equivalent to most of the Breathitt formation of Pennsylvanian age. The regional southeast dip of the rocks is interrupted by the Irvine-Paint Creek fault, the Caney anticline, the Grape Creek syncline, and the Johnson Creek fault.
Date: 1957
Creator: Adkison, W. L.
Partner: UNT Libraries Government Documents Department
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Fluorspar Deposits Near Meyers Cove, Lemhi County, Idaho

Description: Abstract: The fluorspar deposits near Meyers Cove, Lemhi County, Idaho, are localized along three groups of shear zones: one group strikes northeast and dips steeply northwestward, another strikes northeast and dips gently northwestward, and the third strikes northwest and dips gently southwestward. The country rocks are tuffs and flows of the Casto volcanics of Permian(?) age and the Challis volcanics of late Oligocene or early Miocene age. The known deposits are in a belt about 3 miles long a… more
Date: 1954
Creator: Cox, D. C.
Partner: UNT Libraries Government Documents Department
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Niobium (Columbium) and Titanium at Magnet Cove and Potash Sulphur Springs, Arkansas

Description: From Abstract: Niobium (columbium) and titanium occur in several minerals and rocks of the Magnet Cove and Potash Sulphur Springs areas. Niobium is in demand for use in high-temperature and noncreep steels; titanium metal is becoming an important structural material. The Magnet Cove and Potash Sulphur Springs areas are in central Arkansas between the communities of Malvern and Hot Springs. They are underlain by similar alkalic igneous complexes consisting of nepheline syenite, more basic alkali… more
Date: 1954
Creator: Fryklund, Verne Charles, Jr.; Harner, R. S. & Kaiser, E. P.
Partner: UNT Libraries Government Documents Department
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Radioactivity Investigations at Ear Mountain, Seward Peninsula, Alaska, 1945

Description: From abstract: Radioactive material in apparently significant amounts was recognized in heavy-mineral concentrates from the gravels of four streams that head in Ear Mountain, Alaska, when collections of the United States Geological Survey were examined for radioactivity in the winter of 1944-45. This area, on the north side of the Seward Peninsula, attracted attention in 1901-02 when cassiterite was discovered in the streams. Subsequent attempts were made to develop copper- and tin-bearing lode… more
Date: 1955
Creator: Killeen, P. L. & Ordway, Richard J.
Partner: UNT Libraries Government Documents Department
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Geology and Ore Deposits in the Reid Inlet Area Glacier Bay, Alaska

Description: From abstract: A gold-bearing area of about 7% square miles near the head of Glacier Bay between Reid and Lamplugh Glaciers was first discovered by Mr. Joseph Ibach in 1924. The dominant rock type in the area is granodiorite, which is intruded into bedded rocks that may be of Paleozoic age. The bedded rocks consist of conglomerate, limestone, and black graphitic schist. A light-colored quartz diorite younger than the granodiorite crops out south of the mapped area.
Date: 1959
Creator: Rossman, Darwin Lucian
Partner: UNT Libraries Government Documents Department
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