Download or read book The Structure and Stratigraphy of a Portion of the Trout Creek Mountains Harney County Oregon written by Richard W. Carlton and published by . This book was released on 1969 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt: The thesis area is located in the southeastern corner of Harney County, Oregon. This portion of Oregon is situated in the northern part of the Basin and Range province, and is characterized by both mafic and silicic extrusives, and localized nonmarine sediments and tuffs ranging in age from middle Miocene to Recent. The rocks of Miocene and some Pliocene age have been cut by normal faults forming typical Basin and Range structure. The base of the stratigraphic sequence within the thesis area is formed by 775 feet of thin, highly porphyritic basalt flows. On the basis of petrographic and field similarities, these basalts have been correlated with the Steens Basalt of Fuller (1931). Overlying the porphyritic basalts are 980 feet of fine-grained, andesitic basalt flows, and flow breccias. These basalts superficially resemble the Steens Mountain volcanic series of Fuller but they occupy a higher stratigraphic position and may be correlative with the Owyhee Basalt of Renick (1931). Covering the andesitic basalt, but generally poorly exposed are approximately 155 feet of vitric and lithic-vitric air fall tuffs. These tuffs and the overlying ash flow tuffs may be genetically related and probably represent a period of silicic extrusion within the thesis area. Four ash flow tuffs are recognized and described. They appear to have been extruded over a short period of time and may represent a compound cooling unit. The basal ash flow (unit one) is 330 feet thick and characterized by large flattened pumice fragments in the middle welded zone. Covering the basal ash flow is a 230 foot thick ash flow (unit two) composed of a nonwelded base, a dense vitrophyre, and a thick partly welded upper zone. A third ash flow (unit three) whose maximum thickness is 225 feet overlies unit two and is characterized by extremely flattened pumice fragments and platiness. A fourth ash flow (unit four) found only on Red Mountain overlies unit three and has a maximum thickness of 10 feet. The ash flow tuffs are probably not related to the Canyon Rhyolite of Merriam (1910) and are middle to late Miocene in age. Locally overlying the ash flow tuffs is a thick sequence of varicolored, thickly bedded vitric tuffs. These tuffs are correlated with the Trout Creek Formation on the basis of similar stratigraphic position. Stratigraphically above the Trout Creek Formation is a series of coarse angular conglomerates and fine lacustrine sediments which were deposited in stream channels, and as alluvial fans and slope wash during periods of high stream discharge. These sediments are correlated with the Turn-Turn Conglomerates found on the west side of Pueblo Valley. The Turn-Turn Conglomerates are covered on the west by Pliocene and Pleistocene terrace deposits composed primarily of unconsolidated volcanic gravels and pebbles. Structurally the western half of the thesis area is part of the Pueblo Valley graben while the eastern half forms the Trout Creek Mountains. Most of the faults cut the ash flow tuffs and strike within 30° east or west of due north. Donath postulates that this fault pattern may represent original conjugate strike slip shears caused by a north-south maximum principal stress. At a later time block faulting occurred along the previously formed shear zones forming the present topography.

Download or read book Stratigraphy and Structure of the Western Trout Creek and Northern Bilk Creek Mountains Harney County Oregon and Humboldt County Nevada written by Scott Alan Minor and published by . This book was released on 1986 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Mineral Resources of the Disaster Peak Wilderness Study Area Harney and Malheur Counties Oregon and Humboldt County Nevada written by Scott A. Minor and published by . This book was released on 1988 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Theses and Dissertations 1966 1970 Oregon State University written by Margaret Basilia Guss and published by . This book was released on 1973 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Bibliographic Series written by and published by . This book was released on 1973 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Theses and Dissertations on the Geology of Oregon written by and published by . This book was released on 1982 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Theses and Dissertations Oregon State University written by and published by . This book was released on 1973 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Geology of the Stinking Water Creek Area Harney County Oregon written by Cecilia Dolores Gregory and published by . This book was released on 1981 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Masters Theses and Doctoral Dissertations in the Pure and Applied Sciences Accepted by Colleges and Universities of the United States written by and published by . This book was released on 1968 with total page 536 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book U S Geological Survey Bulletin written by and published by . This book was released on 1983 with total page 584 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Bibliography and Index of Geology written by and published by . This book was released on 1987 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Master s Theses and Doctoral Dissertations in the Pure and Applied Sciences written by and published by . This book was released on 1970 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Bibliography of the Geology and Mineral Resources of Oregon written by Caroline P. R. Hulick; and published by . This book was released on 1978 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Ore Bin written by and published by . This book was released on 1970 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Open file Report written by and published by . This book was released on 1983 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Bibliography of the Geology and Mineral Resources of Oregon written by and published by . This book was released on 1980 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Bulletin State of Oregon Department of Geology and Mineral Industries written by Oregon. Department of Geology and Mineral Industries and published by . This book was released on 1937 with total page 432 pages. Available in PDF, EPUB and Kindle. Book excerpt: