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• 1. [Article] The Ore bin ; Vol. 32 No. 5 (May 1970)

  This report summarizes results of geologic mapping in the South Umpqua Falls region of the Western Cascade Range in Douglas County, southwestern Oregon (plate 1). Rocks of the Western Cascades range in ...

  Citation × Citation Citation Abstract Copy Title: The Ore bin ; Vol. 32 No. 5 (May 1970) Author: Kays, Marvin Allan, 1934-, Oregon. Dept. of Geology and Mineral Industries This report summarizes results of geologic mapping in the South Umpqua Falls region of the Western Cascade Range in Douglas County, southwestern Oregon (plate 1). Rocks of the Western Cascades range in age from late Eocene to late Miocene and consist of deformed and partially altered flows, pyroclastic rocks, and interlayered sedimentary rocks (Peck and others, 1964). In the area of this investigation, Tertiary units include the Colestin Formation of late Eocene age, the Little Butte Volcanic Series of Oligocene and early Miocene age, and the Sardine Formation of possible middle and late Miocene age. It is notable that older Tertiary rocks, present both to the north and to the south, are absent beneath the rocks of the Colestin Formation in this region. In the vicinity of Tiller, west of the mapped area, pre-Tertiary plutonic and metamorphic rocks form the basement and are overlain with profound unconformity by strata of the Colestin Formation. Rocks of the Western Cascade Range are capped to the east by younger volcanic rocks of the High Cascade Range. Title: The Ore bin ; Vol. 32 No. 5 (May 1970) Author: Kays, Marvin Allan, 1934-, Oregon. Dept. of Geology and Mineral Industries This report summarizes results of geologic mapping in the South Umpqua Falls region of the Western Cascade Range in Douglas County, southwestern Oregon (plate 1). Rocks of the Western Cascades range in age from late Eocene to late Miocene and consist of deformed and partially altered flows, pyroclastic rocks, and interlayered sedimentary rocks (Peck and others, 1964). In the area of this investigation, Tertiary units include the Colestin Formation of late Eocene age, the Little Butte Volcanic Series of Oligocene and early Miocene age, and the Sardine Formation of possible middle and late Miocene age. It is notable that older Tertiary rocks, present both to the north and to the south, are absent beneath the rocks of the Colestin Formation in this region. In the vicinity of Tiller, west of the mapped area, pre-Tertiary plutonic and metamorphic rocks form the basement and are overlain with profound unconformity by strata of the Colestin Formation. Rocks of the Western Cascade Range are capped to the east by younger volcanic rocks of the High Cascade Range. Close

• 2. [Article] The Ore bin ; Vol. 32 No. 6 (June 1970)

  Periodic violent eruptions from many different centers during Cenozoic time deposited vast quantities of pyroclastic material as ash-flow tuffs over most of Oregon, although the Coast Ranges and isolated ...

  Citation × Citation Citation Abstract Copy Title: The Ore bin ; Vol. 32 No. 6 (June 1970) Author: Walker, George Walton, 1921-, Oregon. Dept. of Geology and Mineral Industries Periodic violent eruptions from many different centers during Cenozoic time deposited vast quantities of pyroclastic material as ash-flow tuffs over most of Oregon, although the Coast Ranges and isolated patches elsewhere in the state appear to have been spared these recurring inundations. Eruptions occurred at different times throughout the Cenozoic, and for purposes of description, they can be separated into three age groups: an older one of Eocene, Oligocene, and Miocene age, an intermediate one of early and middle Pliocene age, and a young group of late Pliocene, Pleistocene, and Holocene age. Some of these ash-flow tuffs are of small volume, less than a cubic mile, and are related to fissure vents, small domal complexes, or calderas from which several kinds of volcanic products were erupted. A few cover thousands of square miles, have volumes of tens of cubic miles, and apparently are related to a large-scale basinal collapse structure and associated calderas. Most ash-flow tuffs are rhyolite or dacite; a few are peralkaline soda rhyolite. Older ash-flow tuffs are commonly diagenetically altered to a variety of secondary minerals; of the younger tuffs, only those that erupted into shallow lakes exhibit comparable alteration. Title: The Ore bin ; Vol. 32 No. 6 (June 1970) Author: Walker, George Walton, 1921-, Oregon. Dept. of Geology and Mineral Industries Periodic violent eruptions from many different centers during Cenozoic time deposited vast quantities of pyroclastic material as ash-flow tuffs over most of Oregon, although the Coast Ranges and isolated patches elsewhere in the state appear to have been spared these recurring inundations. Eruptions occurred at different times throughout the Cenozoic, and for purposes of description, they can be separated into three age groups: an older one of Eocene, Oligocene, and Miocene age, an intermediate one of early and middle Pliocene age, and a young group of late Pliocene, Pleistocene, and Holocene age. Some of these ash-flow tuffs are of small volume, less than a cubic mile, and are related to fissure vents, small domal complexes, or calderas from which several kinds of volcanic products were erupted. A few cover thousands of square miles, have volumes of tens of cubic miles, and apparently are related to a large-scale basinal collapse structure and associated calderas. Most ash-flow tuffs are rhyolite or dacite; a few are peralkaline soda rhyolite. Older ash-flow tuffs are commonly diagenetically altered to a variety of secondary minerals; of the younger tuffs, only those that erupted into shallow lakes exhibit comparable alteration. Close

• 3. [Article] The Ore bin ; Vol. 27 No. 2 (February 1965)

  A brief history of the Oregon Portland Cement Co. / F. E. McCaslin -- The age of Clear Lake, Oregon / G. T. Benson -- Oregon's lost meteorites / Erwin F. Lange.

  Citation × Citation Citation Abstract Copy Title: The Ore bin ; Vol. 27 No. 2 (February 1965) Author: Benson, Gilbert Thomas, 1929-, McCaslin, F. E., Lange, Erwin F., Oregon. Dept. of Geology and Mineral Industries A brief history of the Oregon Portland Cement Co. / F. E. McCaslin -- The age of Clear Lake, Oregon / G. T. Benson -- Oregon's lost meteorites / Erwin F. Lange. Title: The Ore bin ; Vol. 27 No. 2 (February 1965) Author: Benson, Gilbert Thomas, 1929-, McCaslin, F. E., Lange, Erwin F., Oregon. Dept. of Geology and Mineral Industries A brief history of the Oregon Portland Cement Co. / F. E. McCaslin -- The age of Clear Lake, Oregon / G. T. Benson -- Oregon's lost meteorites / Erwin F. Lange. Close

• 4. [Article] The Ore bin ; Vol. 27 No. 7 (July 1965)

  Introduction -- Cones and flows of questionable recent age -- Volcanic history of the Sand Mountain Lava Field -- Eruptive rocks from Inacessible alignment and Twin Craters -- Hoodoo Butte -- History of ...

  Citation × Citation Citation Abstract Copy Title: The Ore bin ; Vol. 27 No. 7 (July 1965) Author: Taylor, Edward M., 1933-, Oregon. Dept. of Geology and Mineral Industries Introduction -- Cones and flows of questionable recent age -- Volcanic history of the Sand Mountain Lava Field -- Eruptive rocks from Inacessible alignment and Twin Craters -- Hoodoo Butte -- History of the Belknap Volcano -- Blue Lake Crater -- The Spatter Cone Chain -- Sims and Condon Buttes -- Volcanic history of Yapoah Cone and related vents -- Volcanic history of Four-in-Once Cone and related vents -- Volcanic history of Collier Cone -- Continuity in the volcanic record -- Acknowledgment -- Glossary of selected terms -- References Title: The Ore bin ; Vol. 27 No. 7 (July 1965) Author: Taylor, Edward M., 1933-, Oregon. Dept. of Geology and Mineral Industries Introduction -- Cones and flows of questionable recent age -- Volcanic history of the Sand Mountain Lava Field -- Eruptive rocks from Inacessible alignment and Twin Craters -- Hoodoo Butte -- History of the Belknap Volcano -- Blue Lake Crater -- The Spatter Cone Chain -- Sims and Condon Buttes -- Volcanic history of Yapoah Cone and related vents -- Volcanic history of Four-in-Once Cone and related vents -- Volcanic history of Collier Cone -- Continuity in the volcanic record -- Acknowledgment -- Glossary of selected terms -- References Close