Download or read book The Beaverhead Formation written by Robert T. Ryder and published by . This book was released on 1968 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Guidebook Annual Field Conference written by Montana Geological Society. Field Conference and published by . This book was released on 1967 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Stratigraphic Studies in Southwestern Montana and Adjacent Idaho lower Tertiary Anaconda Conglomerate and Mesoproterozoic Gunsight Formation written by and published by . This book was released on 2005 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Stratigraphy of Mid Cretaceous Blackleaf and Lower Part of the Frontier Formations in Parts of Beaverhead and Madison Counties Montana written by T. S. Dyman and published by . This book was released on 1988 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Geology of Part of the Snowcrest Range Beaverhead County Montana written by George K. Brasher and published by . This book was released on 1950 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Bedrock Geology and Stratigraphy of the Mississippian and Early Pennsylvanian Rocks of the Southeast Flank Armstead Anticline Beaverhead County Montana written by Gail Darice Hildreth and published by . This book was released on 1980 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Stratigraphy and Structure of Dixon Mountain Little Water Canyon Area Beaverhead County Montana written by Richard Alan Klecker and published by . This book was released on 1980 with total page 446 pages. Available in PDF, EPUB and Kindle. Book excerpt: Approximately 23 square miles of the east-central part of the Tendoy Range are included in the thesis area which lies three miles west of Dell, Montana. Rocks ranging in age from Late Mississippian to Recent are exposed in the study area. The upper Paleozoic section includes approximately 4,200 feet (1,281 m.) of strata which are divided into four formations. The nine formations of Mesozoic aae total approximately 2,960 feet (903 m.) plus part of the Cretaceous-Tertiary Beaverhead Formation. Cenozoic strata in the thesis area include Beaverhead conglomerates, basaltic andesite flows, tuffs, and breccias, and unconsolidated gravels, alluvium, and alluvial fan gravels. The thesis area was examined in detail to define formation distribution and structural complications. The Triassic and Jurassic (Ellis Group) rocks were examined specifically in an effort to interpret their depositional environments. Sedimentary structures, fossils, and petrographic evidence indicate a shallow subtidal and intertidal setting for the deposition of Triassic rocks. Algal laminated strata within the Woodside Formation have not previously been described. Much of the Ellis Grout:, was deposited under shallow subtidal and locally shoaling conditions. Glauconite calcarenites in the Swift Formation may represent deposition in sand waves. Folding and faulting within the thesis area represent the overlapping influence of geosynclinal and cratonic tectonism in the hinge line setting of the Tendoy Range. The imposition of a southward-plunging anticline on a southwestward-plunging syncline has resulted in the overturning of the northern limb of the syncline. A low-angle thrust with eastward vergence has been developed in the Dry Canyon area. The thrust has been cut by a later high-angle reverse fault. White Knob strata (Mississippian) have been carried into the western margin of the thesis area on the Medicine Lodge thrust. The economic possibilities are not encouraging. The phosphate deposits of the thesis area have been analyzed and deemed uneconomical. Distance from intrusions precludes the chance of significant mineralization in the area. The petroleum potential for the area is doubtful. Late Cretaceous folding and erosion may have allowed escape of hydrocarbons from the potential source and reservoir rocks of the region. However, the Medicine Lodge thrust sheet may conceal structural and stratigraphic configurations capable of trapping oil and gas.

Download or read book Geological Survey Professional Paper written by and published by . This book was released on 1949 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Redefinition of Frontier Formation written by Russell G. Tysdal and published by . This book was released on 1991 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book U S Geological Survey Professional Paper written by and published by . This book was released on 1984 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Geological Survey Professional Paper written by and published by . This book was released on 1982 with total page 858 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Belt Basin Window to Mesoproterozoic Earth written by John S. MacLean and published by Geological Society of America. This book was released on 2016-06-01 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt: With its thickness of more than 15 km of strata, covering some 200,000 km2, the Belt basin displays one of the planet's largest, best-exposed, most accessible, and best-preserved sequences of Mesoproterozoic sedimentary and igneous rocks. This volume focuses on research into this world-class province; kindles ideas about this critical era of Earth evolution; and covers aspects of the basin from its paleontology, mineralogy, sedimentology, and stratigraphy to its magmatism, ore deposits, geophysics, and structural geology.

Download or read book U S Geological Survey Bulletin written by and published by . This book was released on 1983 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Structure and Stratigraphy of the Little Sheep Creek Area Beaverhead County Montana written by R. Kumbe Sadler and published by . This book was released on 1980 with total page 588 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Middle and West Forks of Little Sheep Creek in the southern Tendoy Range have incised valleys across Cenozoic structural features exposing strata that range in age from the Mississippian to the Neoene. Paleozoic strata are 1,349 m thick and belong to the Mission Canyon Limestone, the Big Snowy, Amsden, Quadrant, and Priosphoria FormationS. The Scott Peak Formation of the White Knob Group of Idaho is allochtononous and forms the upper plate of the Medicine Lodge thrust. Paleozoic and Triassic strata of the thesis area represent sedimentation across a transition zone between a stable craton to the east and the Cordilleran miogeosyncline to the west. Regional unconformities are recognized locally at the top of the Mission Canyon Limestone and the Phosphoria and Thaynes Formations, but not at the top o the Big Snowy, Amsden, or Quadrant Formations, Mesozoic strata have a total thickness of 1,404 m and belong to the Dinwoody, Woodside, and Thaynes Formations, the newly recognized Gypsum Spring Tongue of the Twin Creek Formation, the Sawtooth and Rierdon Formations of the Ellis Group, the Morrison and Kootenai Formations, the Colorado Shale, and the Beaverhead Formation. Cenozoic strata are represented by the newly named Round Timber limestone (informal) of the Medicine Lodge beds (Miocene) and the Edie School rhyolite (Pliocene). Detailed stratigraphic and petrographic analyses were made of the Triassic Dinwoody, Woodside, and Thaynes Formations, the Jurassic Gypsum Spring Tongue, and the Niocene Round Timber limestone in order to determine environments of deposition. The limestones, calcareous siltstones, and silty limestones of the Dinwoody and Thaynes Formations were deposited in a shallow marine shelf environment as a result of two transgressive pulses separated by an Early Traissic regression. The Triassic seas had transgressed eastward onto the craton from the miogeosyncline. The Dinwoody arid Thaynes fauna indicate normal salinities and open marine conditions; the widespread regional distribution of the limestone-siltstone facies indicates broad equable conditions for sedimentation. Deposition was primarily a tractive process genarated by storm-driven, tidal, and long-shore currents within a maximum depth of approximately 50 m. The Early Triassic regressive phase is represented by the deposition of the variegated siltstone, sandstone, limestone, and dolomite of the Woodside Formation in a tidal flat environment. The Gypsum Spring Tongue consists of interbedded variegated siltstone, sandstone, limestone, dolomite, and limestone conglomerate that were deposited in a tidal flat and restricted marginal marine environment extending east from southwestern Montana and eastern Idaho across Wyoming arid southern Montana. The Middle Jurassic sea transgressed South across the North American continent. The Miocene Round Timber limestone was deposited in a fresh-water lake in which calcite was being deposited as encrustations on the green algae Chara and as a precipitate directly from solution. The folding and faulting within the thesis area are the result of cratonic and miogeosynclinal responses to Cretaceous-Early Tertiary orogenesis. A southwestward-plunging anticline has been refolded into northeastward-yielding, overturned, doubly-plunging folds oriented northwest-southeast. High angle reverse faults of minor displacement have occurred along the southeastern limb of Garfield anticline and within the axis of the Seybold syncline. Post-Laramide relaxation of compressional forces has caused north- and northwest-oriented normal faults that transect earlier structures. Sandstone and limestone of the Scott Peak Formation of the White Knob Group were implaced along the Medicine Lodge thrust.

Download or read book Geological Survey Professional Paper written by Geological Survey (U.S.) and published by . This book was released on 1979 with total page 578 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Mississippian and Pennsylvanian Carboniferous Systems in the United States written by and published by . This book was released on 1980 with total page 578 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Shorter Contributions to the Stratigraphy and Geochronology of Upper Cretaceous Rocks in the Western Interior of the United States written by Geological Survey (U.S.) and published by . This book was released on 1995 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: