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Cenozoic Geology in the Mammoth Area Pinal County, Arizona

Description: From introduction: "The purpose of this report is to show how mapping of discrete units of the valley fill may lead to a broadened understanding of Cenozoic history of intermontane basins in Arizona. The area described is in the vicinity of Mammoth Arizona where deep dissection has exposed a complex sequence of terrestrial deposits and related rocks."
Date: 1963
Creator: Heindl, L. A.
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The Eastern Front of the Bitterroot Range, Montana

Description: From abstract: The origin of the gneissic rocks on the eastern border of the Idaho batholith in the Bitterroot Range, near Hamilton, Mont., has long been in dispute. Lindgren regarded these rocks as the product of stresses related to a normal fault along the front of the range with an eastward dip of about 150. He thought both the hanging wall and the footwall had moved, with a total displacement along the fault plane of at least 20,000 feet. The faulting was believed to have been so recent as … more
Date: 1952
Creator: Ross, Clyde P.
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Nonopaque Heavy Minerals in Sandstone of Jurassic and Cretaceous Age in the Black Hills, Wyoming and South Dakota

Description: The following report describes the examinations of the nonopague heavy minerals in sandstone found in the Black Hills in northeastern Wyoming and western South Dakota. The studies were made to determine if differences in the shapes of the grains and proportions of minerals are sufficiently distinctive to be used in subdividing and correlating formations.
Date: 1964
Creator: Mapel, W. J.; Chisholm, Wayne A. & Bergenback, Richard Edwards
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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.
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